[The effect of new ACTH fragments on the behaviors of self-stimulation, avoidance and grooming in rabbits].
We studied the influence of new cyclic analogues of ACTH fragments EHFRWGKPVG-NH2 and KHFRVG-NH2 on self-stimulation (SS) and active avoidance (AA) behaviour. Intraventricular injection of EHFRWGKPVG-NH2 in low doses (0.5-2.5 mcg) was shown to increase, that in higher doses (4-5 mcg) to decrease SS frequency. Injection of KHFRWG-NH2 in doses of 0.1-5 mcg resulted in 25-30% decrease of SS frequency during the first 15 min, its subsequent return to the background level and repeated decrease. In 24-48 h SS was 5-8% higher than the background level and practically was unchanged in the course of 2 h of experiment. When testing AA behaviour EHFRWGKPVG-NH2 in doses of 0.5-2 mcg induced twice shorter "anxiety time" and longer latency of AA. Both fragments (0.1-5 mcg) evoked excessive grooming. These effects persisted for 24-72 h. The role of the cyclic analogues of ACTH fragments in the mechanisms of positive and negative reinforcement is discussed.
Burchuladze
R A
RA
Chabak
R
R
Chippens
G I
GI
D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation / Q000379:methods; D006120:Grooming / Q000187:drug effects* / Q000502:physiology; D007026:Hypothalamic Area, Lateral / Q000502:physiology; D007276:Injections, Intraventricular; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology*; D010456:Peptides, Cyclic / Q000494:pharmacology*; D011817:Rabbits; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D012653:Self Stimulation / Q000187:drug effects* / Q000502:physiology; D013329:Structure-Activity Relationship; D014697:Ventromedial Hypothalamic Nucleus / Q000502:physiology
D010446:Peptide Fragments; D010456:Peptides, Cyclic; C086279:lysyl-histidyl-phenylalanyl-arginyl-tryptophyl-glycinamide; D000324:Adrenocorticotropic Hormone; C086281:glutamyl-histidyl-phenylalanyl-arginyl-tryptophyl-glycyl-lysyl-prolyl-valyl-glycinamide cyclic peptide
Vliianie novykh fragmentov AKTG na povedenie samostimuliatsii, izbeganiia i gruminga u krolikov.