Effects of a new TRH analogue, YM-14673 on a passive avoidance test as a possible criterion of improvement in cognitive disturbance in rodents.
Effects of a new TRH analogue, YM-14673 (N alpha-[[(S)-4-oxo-2-azetidinyl]carbonyl]-L-histidyl-L-prolinamide dihydrate) on cognitive disturbance of passive avoidance response were studied in rodents in comparison with those of TRH and CDP-choline. The latency for entering from the illuminated into the dark compartments was shortened in anoxia and scopolamine-treated rats, cycloheximide-treated mice and cerebral ischemic gerbils. The shortened latency in these models was prolonged by administration of both YM-14673 and TRH in doses without effect on spontaneous movement. YM-14673 was about 10 times more potent than TRH in ameliorating the cognitive disturbance, whereas CDP-choline showed no influence on the learning ability. These results suggest that YM-14673 and TRH possess facilitatory effects on cerebral function and that YM-14673 was distinct from CDP-choline in pharmacological profile.
D000647:Amnesia / Q000188:drug therapy / Q000209:etiology; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001384:Azetidines / Q000494:pharmacology* / Q000627:therapeutic use; D001385:Azetines / Q000494:pharmacology*; D002545:Brain Ischemia / Q000150:complications; D003072:Cognition Disorders / Q000188:drug therapy*; D003244:Consciousness Disorders / Q000188:drug therapy*; D003513:Cycloheximide; D004151:Dipeptides / Q000494:pharmacology* / Q000627:therapeutic use; D005849:Gerbillinae; D051379:Mice; D051381:Rats; D012601:Scopolamine; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology* / Q000627:therapeutic use
D001384:Azetidines; D001385:Azetines; D004151:Dipeptides; D013973:Thyrotropin-Releasing Hormone; C054995:azetirelin; D003513:Cycloheximide; D012601:Scopolamine