Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K49/00—Preparations for testing in vivo
  • A61K49/0004—Screening or testing of compounds for diagnosis of disorders, assessment of conditions, e.g. renal clearance, gastric emptying, testing for diabetes, allergy, rheuma, pancreas functions
  • A61K49/0008—Screening agents using (non-human) animal models or transgenic animal models or chimeric hosts, e.g. Alzheimer disease animal model, transgenic model for heart failure
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/435—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with one nitrogen as the only ring hetero atom
  • A61K31/44—Non condensed pyridines; Hydrogenated derivatives thereof
  • A61K31/445—Non condensed piperidines, e.g. piperocaine
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/435—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with one nitrogen as the only ring hetero atom
  • A61K31/44—Non condensed pyridines; Hydrogenated derivatives thereof
  • A61K31/445—Non condensed piperidines, e.g. piperocaine
  • A61K31/4515—Non condensed piperidines, e.g. piperocaine having a butyrophenone group in position 1, e.g. haloperidol
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/495—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with two or more nitrogen atoms as the only ring heteroatoms, e.g. piperazine or tetrazines
  • A61K31/496—Non-condensed piperazines containing further heterocyclic rings, e.g. rifampin, thiothixene or sparfloxacin
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/495—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with two or more nitrogen atoms as the only ring heteroatoms, e.g. piperazine or tetrazines
  • A61K31/505—Pyrimidines; Hydrogenated pyrimidines, e.g. trimethoprim
  • A61K31/519—Pyrimidines; Hydrogenated pyrimidines, e.g. trimethoprim ortho- or peri-condensed with heterocyclic rings
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/55—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole
  • A61K31/551—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole having two nitrogen atoms, e.g. dilazep
  • A61K31/5513—1,4-Benzodiazepines, e.g. diazepam or clozapine
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K31/00—Medicinal preparations containing organic active ingredients
  • A61K31/33—Heterocyclic compounds
  • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
  • A61K31/55—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole
  • A61K31/554—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole having at least one nitrogen and one sulfur as ring hetero atoms, e.g. clothiapine, diltiazem
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P25/00—Drugs for disorders of the nervous system
  • A61P25/18—Antipsychotics, i.e. neuroleptics; Drugs for mania or schizophrenia
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P25/00—Drugs for disorders of the nervous system
  • A61P25/28—Drugs for disorders of the nervous system for treating neurodegenerative disorders of the central nervous system, e.g. nootropic agents, cognition enhancers, drugs for treating Alzheimer's disease or other forms of dementia
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P43/00—Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D417/00—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00
  • C07D417/02—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00 containing two hetero rings
  • C07D417/12—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by group C07D415/00 containing two hetero rings linked by a chain containing hetero atoms as chain links
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
  • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
  • G01N33/5005—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells
  • G01N33/5008—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics
  • G01N33/5082—Supracellular entities, e.g. tissue, organisms
  • G01N33/5088—Supracellular entities, e.g. tissue, organisms of vertebrates

Definitions

• the present invention relates to an in vivo screening method of a therapeutic agent for improving memory/learning dysfunctions by schizophrenia.
• Glutamic acid is a most popular excitatory neurotransmitter in the central nervous system, and the receptors thereof are classified broadly into an NMDA type, an ⁇ -amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA) type, a kainate type, and a metabotropic type. It is revealed that the NMDA type receptor plays an important role in the completion of the long-term potentiation (LTP), which is an electrophysiologically basal process of the memory/learning functions (cf., Science 285: 1870-1874 (1999)).
• LTP long-term potentiation
• an NMDA receptor antagonist may induce memory/learning dysfunctions in various memory/learning tasks such as a passive avoidance response, a radial maze, a T or Y maze, a water maze, a place or object recognition, an autoshaping learning task, and a lever-pressing task (cf., Brain Res Rev 41: 268-287 (2003)).
• PCP or ketamine which is also an NMDA receptor antagonist, induces cognitive dysfunctions in humans (cf., Psychopharmacology 169: 215-233 (2003)). Namely, it is a common opinion among the electrophysiological level, the animal level and the human level that the NMDA type receptor plays an important rule in the memory/learning process.
• PCP and ketamine which are an NMDA receptor antagonist, induce the major symptoms of schizophrenia in normal humans including cognitive dysfunction, positive-negative symptoms, and induce the exacerbation of symptoms in patients with schizophrenia (cf., Am J Psychiatry 158: 1367-1377 (2001), Psychopharmacology 169: 215-233 (2003)):
• N-acetyl-aspartyl glutamate (NAAG) having an NMDA antagonistic activity is observed in patients with schizophrenia (cf., Am J Psychiatry 158: 1367-1377 (2001)), and the change in the amount of mRNA and proteins of NMDA type receptor subunit and NMDA receptor-related protein is observed in patients with schizophrenia (cf., Am J Psychiatry 157: 1811-1823 (2000), Am J Psychiatry 160: 1100-1109 (2003), Society for Neuroscience Program No. 754.4. (2003)):
• Schizophrenia is associated with various cognitive dysfunctions such as attention, memory, learning, executive functions, but it is reported that among these functions, especially a certain memory function is selectively and seriously damaged.
• memory is classified broadly into procedural memory and declarative memory.
• the declarative memory is further classified into short-term memory/working memory and a long-term memory/reference memory. It is reported that in schizophrenia, the declarative memory including both of the working memory and the reference memory is selectively damaged, and further, among them, the damage of the reference memory is most serious. Recently, it is reported that the cognitive dysfunction including such a reference memory dysfunction is the most important predictive factor of social daily ability and professional ability, and a quality of life of patients with schizophrenia.
• an easy model for evaluating drug efficacy (1) being capable of reflecting reference memory dysfunction, which is the most serious cognitive dysfunction in schizophrenia (i.e., face validity, similarities of symptoms); (2) being associated with NMDA receptor hypofunction, which is a most possible cause for schizophrenia (i.e., construct validity, similarities of the mechanism of onset); and (3) being capable of detecting an excellent drug efficacy of an atypical anti-psychotic agent rather than that of a typical anti-psychotic agent (predictive validity, predictability of clinical drug efficacy), is considered to be quite useful in the research and development of a therapeutic agent for cognitive dysfunction, a core symptom of schizophrenia, but such an animal model has not been known yet until now.
• various tasks consisting of both of the training session, and the testing session being carried out after a prescribed period from the testing session, can be used in order to study a reference memory.
• the animals are made to learn an avoidance response such as electroconvulsive shock (passive or active avoidance response), a task of reaching to a platform which is not visible below water (a water maze task), a task of fetching a food after getting through a maze task or a task of avoiding an electroconvulsive shock (radial maze task, Y or T maze task), a task of recognizing and searching a novel place or object, a task of pressing a lever for obtaining a food, etc., and further they are made to acquire the memory thereof.
• electroconvulsive shock passive or active avoidance response
• a task of reaching to a platform which is not visible below water a water maze task
• a task of fetching a food after getting through a maze task or a task of avoiding an electroconvulsive shock radial
• the animals are returned to exactly the same experimental environment after a prescribed period therefrom, and they are tested if they can retrieve the acquired memory.
• the animals can memorize all of the specific environment and stimulus which are given to them in a specific order in the training session.
• animals show an abnormal memory retrieval when ethanol or an NMDA type receptor antagonist is administered only in the training session of the reference memory tasks, but not in the testing session (cf., Brain Res 706: 227-232 (1996), Pharmcol Biochem Behav 69: 585-593 (2001)).
• the animals acquire a reference memory depending on the environment in the brain, which is induced by the administration of a drug, and in fact, it is proved that by administering a drug both in the training session and the testing session, the acquired memory can correctly be retrieved.
• a phenomenon is usually called state-dependency.
• an NMDA type receptor subtype NR1 knockdown or NR2A subtype knockout animal are already produced as a concrete example for an animal model showing a chronic hypofunction of NMDA type receptor (cf., Cell 98: 427-436 (1999), J Neurosci 21: 750-757 (2001)).
• the present invention provides a screening method of a therapeutic agent for memory/learning dysfunctions by schizophrenia. More particularly, the present invention provides an animal model for reference memory dysfunction caused by hypofunction of NMDA type receptor as a simple animal model for schizophrenia providing the predictability of the clinical drug efficacy of the existing therapeutic agents.
• the present inventors have intensively studied in order to solve the above problems, and found that the reference memory dysfunction in the animals where NMDA type receptor hypofunction is induced both in the training session and the testing session is specifically improved by an atypical anti-psychotic agent but not by a typical anti-psychotic agent, and further they have confirmed that this evaluation system is a very simple and highly-reproducible evaluation system, and finally they have accomplished the present invention.
• the present invention relates to the following features:
• An in vivo screening method for predicting whether or not a test compound is capable of improving the memory/learning dysfunctions by schizophrenia comprises a step of evaluating the memory/learning functions by employing a model showing glutamic acid N-methyl-D-aspartate (NMDA) type receptor hypofunction as an animal model for schizophrenia, and a reference memory task.
• NMDA glutamic acid N-methyl-D-aspartate
• the reference memory task is a passive avoidance task, an active avoidance task, a water maze task, a radial maze task, a T or Y maze task, a place recognition task, an object recognition task, an autoshaping learning task, or a lever-pressing task.
• model showing an NMDA type receptor hypofunction is an animal model associated with an NMDA type receptor hypofunction due to variation, overexpression, or deficiency of gene of constitutive proteins or relevant proteins of an NMDA type receptor in both of the training session and the testing session of the reference memory task.
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises a substance selected by a screening method as set forth in any one of the above [1] to [5] as an active ingredient.
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises a serotonin 5-HT 1A antagonist selected by a screening method as set forth in any one of the above [1] to [5] as an active ingredient.
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises a choline acetylase inhibitor selected by a screening method as set forth in any one of the above [1] to [5] as an active ingredient.
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises aricept as an active ingredient.
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises quetiapine as an active ingredient.
• the therapeutic agent for the memory/learning dysfunctions by schizophrenia according to the above [10], which comprises as an active ingredient quetiapine in a daily dose of 5 to 270 mg.
• the therapeutic agent for the memory/learning dysfunctions by schizophrenia according to the above [10], which comprises as an active ingredient quetiapine in a daily dose of 15 to 90 mg.
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises clozapine as an active ingredient.
• the therapeutic agent for the memory/learning dysfunctions by schizophrenia according to the above [13], which comprises as an active ingredient clozapine in a daily dose of 0.2 to 34.5 mg.
• the therapeutic agent for the memory/learning dysfunctions by schizophrenia according to the above [13], which comprises as an active ingredient clozapine in a daily dose of 0.7 to 11.5 mg.
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises as an active ingredient an imide derivative of the formula [1]: ⁇ wherein Z is a group of the formula: (in which B is a carbonyl or a sulfonyl; R 1 R 2 , R 3 and R 4 are independently a hydrogen atom or a lower alkyl, provided that R 1 and R 2 , or R 1 and R 3 may combine each other to form a hydrocarbon ring, or R 1 and R 3 may combine each other to form an aromatic hydrocarbon ring; said hydrocarbon ring may optionally be cross-linked with a lower alkylene or an oxygen atom; said lower alkylene and hydrocarbon ring may optionally be substituted by at least one alkyl; and n is 0 or 1), D is a group of the formula: (in which A is a hydrocarbon ring optionally be cross-linked with a lower alkylene or an oxygen atom; said lower alkylene and said hydrocarbon ring may optionally be substituted by
• the therapeutic agent for the memory/learning dysfunctions by schizophrenia comprising as an active ingredient the imide derivative or an acid addition salt thereof according to the above [16], wherein Ar is an aromatic heterobicyclic group, naphthyl, benzoyl, phenoxy or phenylthio, and G is N, CH or COH, or —Ar is a biphenylmethylidene, and G is a carbon atom (said aromatic heterobicyclic group, naphthyl, benzoyl, phenoxy, phenylthio and biphenylmethylidene may optionally be substituted by at least one group selected from a lower alkyl, a lower alkoxy and a halogen atom).
• the therapeutic agent for the memory/learning dysfunctions by schizophrenia comprising as an active ingredient the imide derivative or an acid addition salt thereof according to the above [16], wherein Ar is an aromatic heterocyclic group condensed with a benzene ring, or naphthyl, benzoyl, phenoxy or phenylthio (said aromatic heterocyclic group condensed with a benzene ring, naphthyl, benzoyl, phenoxy, and phenylthio may optionally be substituted by at least one group selected from a lower alkyl, a lower alkoxy and a halogen atom), and G is N, CH or COH.
• the therapeutic agent for the memory/learning dysfunctions by schizophrenia comprising as an active ingredient the imide derivative or an acid addition salt thereof according to the above [16], wherein Z is a group of the formula: (in which -L- is a single bond or a double bond, E is a lower alkylene optionally substituted by a lower alkyl, or an oxygen atom, R 5 is a hydrogen atom or a lower alkyl, and B is the same as defined in the above [14]); a group of the formula: (in which -L-, E, R 5 and B are as defined above); a group of the formula: (in which R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 are independently a hydrogen atom or a lower alkyl, or the adjacent two groups of R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia comprising as an active ingredient the imide derivative or an acid addition salt thereof, wherein the compound of the formula [1] is lurasidone:
• a therapeutic agent for the memory/learning dysfunctions by schizophrenia which comprises as an active ingredient a compound of the formula (2): wherein Z is a divalent sulfur, imino, or lower alkylimino; R 11 is a hydrogen atom or an alkyl having 1 to 5 carbon atoms; R 12 is a hydrogen atom, an alkyl having 1 to 5 carbon atoms, a phenyl, an R 15 -substituted phenyl, an aminoalkyl having 1 to 5 carbon atoms, a lower alkylaminoalkyl having 2 to 8 carbon atoms, a lower alkylamino, an amino, or a lower alkylamino; or R 11 and R 12 may combine each other together with N to form a 1-pyrrolidinyl, piperidino,
• the present invention provides a concrete method for evaluating a memory/learning improving activity being specific to certain atypical anti-psychotic agents but not to a typical anti-psychotic agent haloperidol.
• the results obtained by this method are in agreement with the clinical findings that haloperidol shows no improving activity of cognitive dysfunctions, and that atypical anti-psychotic agents exhibit an improving activity of cognitive dysfunctions.
• the memory/learning improving efficacy is recognized with respect to lurasidone, which is under development as a candidate for a novel therapeutic agent for schizophrenia, noradrenaline ⁇ 2 receptor antagonist 1-(2-pyrimidyl)piperazine dihydrochloride (hereinafter, referred to as 1-PP), and serotonin 5-HT 1A receptor antagonist in addition to risperidone, clozapine or quetiapine, by which a candidate for a novel agent for improving cognitive dysfunctions by schizophrenia can be provided.
• 1-PP noradrenaline ⁇ 2 receptor antagonist 1-(2-pyrimidyl)piperazine dihydrochloride
• serotonin 5-HT 1A receptor antagonist in addition to risperidone, clozapine or quetiapine
• the memory/learning improving activity of clozapine and quetiapine is observed at a dose by 10 times or more lower than the dose at which they exhibit an anti-psychotic activity, and hence, a different action mechanism can be speculated.
• the retrieval of reference memory task being acquired with improvement by a drug is done with depending on the state of the NMDA type receptor hypofunction (state-dependent), as a novel and concrete method for evaluating the reference memory dysfunction improving activity of a drug, a method where the NMDA type receptor hypofunction is induced during the period including the training session and the testing session is effective.
• the present invention relates to an in vivo screening method for predicting whether or not a test compound is capable of improving the memory/learning dysfunctions by schizophrenia, wherein said method comprises a step of evaluating the memory/learning function by employing a model showing an NMDA type receptor hypofunction as an animal model for schizophrenia and a reference memory task.
• the reference memory task includes, for example, a passive avoidance task, an active avoidance task, a water maze task, a radial maze task, a T or Y maze task, a place recognition task, an object recognition task, an autoshaping learning task, and a lever-pressing task.
• the reference memory task is composed of two sessions such as training and testing.
• training session an animal is made to learn a certain task and further made to acquire a memory thereof.
• testing session is carried out, and the retention and retrieval of the memory of task at the testing session is quantified.
• a compound having an NMDA type receptor antagonistic activity e.g., MK-801, PCP, ketamine, or a derivative thereof, is administered to animals during both in the training session and the testing session of the reference memory task, or chronically administered to animals during the period including the training session and the testing session, and these animals are used as an animal model showing an NMDA type receptor hypofunction.
• MK-801, PCP, ketamine, or a derivative thereof is administered to animals during both in the training session and the testing session of the reference memory task, or chronically administered to animals during the period including the training session and the testing session, and these animals are used as an animal model showing an NMDA type receptor hypofunction.
• an animal model associated with an NMDA type receptor hypofunction due to variation, overexpression or deficiency of gene of constitutive proteins or relevant proteins of NMDA type receptor in both of the training session and the testing session in the reference memory task can be used as a model showing an NMDA type receptor hypofunction.
• Wistar male rats (7 weeks old) were used.
• Haloperidol (a typical anti-psychotic agent), clozapine, quetiapine, risperidon, olanzapine or aripiprazole (atypical anti-psychotic agent), or lurasidone being under development as a novel anti-psychotic agent was suspended in a 0.5% methyl cellulose (MC) and the resultant suspension was used as a test compound.
• Serotonin 5-HT 1A receptor antagonist WAY-100635 or noradrenaline ⁇ 2 receptor antagonist 1-PP was dissolved in a physiological saline solution (Otsuka Pharmaceutical Co., Ltd.) and used as a test compound.
• MK-801 hydrogen maleate As an NMDA type receptor antagonist, MK-801 hydrogen maleate (SIGMA-ALDRICH M-107) was dissolved in a physiological saline solution (Otsuka Pharmaceutical Co., Ltd.). A test compound (0.3 to 10 mg/kg) or a 0.5% MC or a physiological saline solution as a control was orally or interperitoneally administered to the animals one hour prior to the training session of the passive avoidance task, and MK-801 (0.05 mg/kg) or a physiological saline solution as a control was subcutaneously administered 30 minutes prior to both of the training session and the testing session. For the evaluation of state-dependency of MC-801, MK-801 was administered before the training session, and a physiological saline solution was administered before the testing session instead. The dosing value thereof was 5 ml/kg for each.
• the step-through type passive avoidance response test was carried out in the following manners with the use of an apparatus consisting of a light-dark box, a slide door dividing the light-dark box and a shock generator (manufactured by O'hara & Co., Ltd., PA-2030A, PA-3001A) as an experimental apparatus. Namely, on Day 1 of the experiment, after a test compound and MK-801 were administered, the rats were put into the light box of the experimental apparatus where the back of each rat was directed to the dark box. Then, 10 seconds later, a slide door set at the border between the dark box and the light box was opened. Due to the habits of the rats, once the rats entered into the dark box, the slide door was quickly closed.
• an electroconvulsive shock (0.5 mA, for 3 seconds) was given to the rats.
• the training was terminated, and those animals were dropped in the following experiment for the reasons of training failure.
• the testing session was carried out about 24 hours after the training session. Thirty minutes prior to the testing session, MK-801 or a vehicle thereof, i.e., a physiological saline solution, was subcutaneously administered to the rats.
• the procedures of the testing session were carried out in the same manner to the training session except that no electroconvulsive shock was given.
• the step-through latency at the testing session was measured up to 300 seconds, and the step-through latency over 300 seconds was regarded as 300 seconds.
• the number of animals which showed 300 seconds at the testing session was counted, and the ratio thereof was calculated in percentages (as defined as a % of animals avoiding) in each group.
• the statistical analysis of the % of animals avoiding was done by x 2 test with Bonferroni's correction. The animals were used in a group of 10 to 25 animals per group, and the data was expressed by percentage.
• a drug was administered alone without MK-801, and a dose of the drug to induce the memory/learning dysfunctions in the passive avoidance response was determined. Further a dose less than that dose and to induce no memory/learning dysfunctions was used as an administration dose in the MK/801 models (Table 1).
• the animals to which MK-801 was administered before the training session, and a physiological saline solution was administered before the testing session showed the nearly equal decrease in the step-through latency to that of the animals to which MK-801 was administered both in the training session and the learning session. That is, it was found that the memory dysfunction observed in the cases where MK-801 was administered only before the training session, or before both of the training session and the testing sessions, is not a memory retrieval dysfunction but memory acquisition dysfunction.
• a dose to inhibit 50% of methamphetamine-induced hyperponesis in rats (ED50, mg/kg, p.o.), which reflects anti-psychotic activity, is 65 and about 100 with respect to clozapine and quetiapine, respectively. That is, it is suggested that clozapine and quietiapine show a memory/learning dysfunction improving activity at a dose 65-272 times or 10 times lower than the dose thereof showing anti-psychotic activity, ED50, respectively. Thus, it became apparent that these drugs show its memory/learning dysfunction improving activity in a different action mechanism from that of the anti-psychotic activity thereof.
• a dose thereof for improving memory/learning dysfunctions by schizophrenia should be 0.2-34.5 mg, preferably 0.7-11.5 mg, which are obtained by calculating 150/217-750/65 (i.e., 0.7-11.5 mg) and broadening the obtained range into either direction by about 3 times.
• a dose thereof for improving memory/learning dysfunctions by schizophrenia should be 5-270 mg, preferably 15-90 mg, which is obtained by calculating 150/10-900/10 (i.e., 15-90 mg) and broadening the obtained range into either direction by about 3 times.
• PCP HCl (0.75 mg/kg) was subcutaneously administered instead of MK-801 (0.05 mg/kg) to animals prior to both of the training session and the testing session of the memory/learning task to induce memory/learning dysfunctions, and the memory/learning dysfunction improving activity of a test compound can be evaluated.
• the memory/learning dysfunction improving activity of a test compound can be evaluated under the exactly same conditions as those in Examples 1 and 2, except that ketamine is used instead of MK-801 or PCP HCl.
• an animal showing a variation, overexpression or deficiency of gene of constitutive proteins or relevant proteins of the NMDA type receptor can be utilized.
• Example 1 In the procedures of Examples 1 to 5, either one of an active avoidance task, a water maze task, a radial maze task, a T or Y maze task, a place recognition task, an object recognition task, an autoshaping learning task, and a lever-pressing task can be employed instead of a passive avoidance task, and the exactly same experiment as Example 1 can be carried out.
• Table 1 shows the effects of the drugs on MK-801-induced memory/learning dysfunctions in the passive avoidance task in rats.
• Table 1 shows the effects of the drugs in terms of the percentage of the animals acquiring passive avoidance response (i.e., the percentage of the animals showing a step-through latency of 300 seconds or more in the testing session, that is, the percentage of the animals showing a remarkable memory retention, a % of animals avoiding) in the passive avoidance response test in the rats to which MK-801, an NMDA type receptor antagonist, was administered prior to both of the training session and the testing session.
• the percentage of the animals acquiring passive avoidance response i.e., the percentage of the animals showing a step-through latency of 300 seconds or more in the testing session, that is, the percentage of the animals showing a remarkable memory retention, a % of animals avoiding
• the present invention provides an in vivo screening method of a therapeutic agent for improving memory/learning dysfunctions by schizophrenia.

Landscapes

• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• Medicinal Chemistry (AREA)
• Animal Behavior & Ethology (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Pharmacology & Pharmacy (AREA)
• Biomedical Technology (AREA)
• Epidemiology (AREA)
• Organic Chemistry (AREA)
• Bioinformatics & Cheminformatics (AREA)
• Immunology (AREA)
• Urology & Nephrology (AREA)
• Hematology (AREA)
• Molecular Biology (AREA)
• Cell Biology (AREA)
• Toxicology (AREA)
• Pathology (AREA)
• Neurology (AREA)
• Neurosurgery (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Analytical Chemistry (AREA)
• Biochemistry (AREA)
• General Physics & Mathematics (AREA)
• Physics & Mathematics (AREA)
• Food Science & Technology (AREA)
• Tropical Medicine & Parasitology (AREA)
• Biotechnology (AREA)
• Microbiology (AREA)
• Psychiatry (AREA)
• Zoology (AREA)
• Diabetes (AREA)
• Endocrinology (AREA)
• Rheumatology (AREA)
• Gastroenterology & Hepatology (AREA)

Priority Applications (1)

Applications Claiming Priority (3)

Related Parent Applications (1)

Related Child Applications (1)

Publications (1)

Family

ID=34879367

Family Applications (3)

Family Applications After (2)

Country Status (4)

Cited By (2)

Families Citing this family (12)

Citations (1)

Family Cites Families (22)

• 2005
  • 2005-02-16 EP EP05710541A patent/EP1726952A4/fr not_active Withdrawn
  • 2005-02-16 WO PCT/JP2005/002838 patent/WO2005080976A1/fr not_active Ceased
  • 2005-02-16 EP EP11160001A patent/EP2357474A1/fr not_active Ceased
  • 2005-02-16 US US10/589,804 patent/US20070160537A1/en not_active Abandoned
  • 2005-02-16 JP JP2006510283A patent/JP4847320B2/ja not_active Expired - Lifetime
• 2009
  • 2009-03-11 US US12/401,958 patent/US8835438B2/en not_active Expired - Lifetime
• 2014
  • 2014-08-14 US US14/460,316 patent/US20140356292A1/en not_active Abandoned

Patent Citations (1)

Also Published As

Similar Documents

Legal Events