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S Tadokoro

Publications and source records attributed to S Tadokoro.

157 records · Page 9Linked to original sources
PubMed1975

Analytical study of acquisition on free-operant avoidance response for evaluation of psychotropic drugs in rats.

Systematic research was performed on the acquisition of free-operant (Sidman-type) avoidance response, which is widely used for the study of psychotropic drugs, with the following results: When the training session was fixed at 2 hours once daily, shock-shock (S-S) interval at 5 seconds, and response-shock (R-S) interval variable-20, 30 and 60 seconds, the acquisition speed of the response was almost constant independent of the R-S interval, about 6 sessions being always required. When the S-S and R-S intervals were constantly 5 and 30 seconds, respectively and the length of one session was varying-1, 2 and 4 hours, the behavioral baseline was established after about 6 sessions independently of the length of the session. Thus the cumulative time for the acquisition was shortest when one session was 1 hour long, and longest when it was 4 hours long. There was a linear relation with negative inclination between the logarithm of mean numbers of shock delivered per sessions and the number of sessions. In rapid and exact training of animals for the evaluation of drug effects, one session of an hour per day is adequate. In the evaluation of drug effects on the acquisition process, observation of the shift in logarithmic value of shocks delivered is recommended.

Animals↗
PubMed1975

[Effects of penfluridol, a psychotropic agent, on operant behavior of rats].

Effects of penfluridol, a diphenylbutylpiperidine type psychotropic agent, on operant behavior were investigated and compared with those of chlorpromazine and haloperidol in rats trained on the following 5 schedules. Fixed ratio (FR 30) of food reinforcement and differential water reinforcement of low rate (DRL 20 sec) schedules were used for positively reinforced behaviors. Continuous (Sidman-type) and discriminated avoidance schedules were used for negatively reinforced behaviors. Conditioned suppression of response (CER) under FR 30 developed by stimulus presentation with electric shock was also applied. When 1 mg/kg of penfluridol was given orally, no change was observed in respondings of all the performances. At higher doses (2 approximately 8 mg/kg, p.o.), the respondings were inhibited in proportion to the dosage except in DRL performance, in which only correct response rate decreased at 8 mg/kg. These inhibitory effects were observed more apparently in the negatively reinforced behaviors than in the positively reinforced ones. Furthermore, a clear dose-effect relationship was obtained in the former. CER was not all attenuated by 2 approximately 8 mg/kg of penfluridol, thus a diazepam-like effect was not confirmed. These behavioral effects suggested that penfluridol has neuroleptic properties similar to those observed with chlorpromazine or haloperidol. However, in general, the inhibitory effects reached the maximum level approximately at 16 hr and lasted for 2 approximately 3 days after oral administration of the drug. Intensity of the effect of penfluridol was estimated to be about 1/8 approximately 1/10 that of haloperidol, according to the results obtained in the avoidance performances.

Animals↗