title: Dose-related facilitation and inhibition of passive avoidance behavior by the ACTH 4-9 analog (ORG 2766).
abstract: The effects of "low" and "high" doses of the ACTH 4-9 analog (ORG 2766) were studied on passive avoidance behavior of rats compared to ACTH 4-10 and [D-Phe7] ACTH 4-10. All peptides increased avoidance latency in a dose-dependent manner. However, "high" doses of ORG 2766 (500 and 1000 ng/rat) inhibited passive avoidance retention. "High" amounts of ACTH 4-10 and [D-Phe7] ACTH 4-10 still facilitated passive avoidance behavior. "High" doses of ORG 2766 like "low" amounts of this peptide delayed extinction of active avoidance behavior. "High" doses of [D-Phe7] ACTH 4-10 like "low" amounts of this peptide facilitated extinction of active avoidance behavior. The substituted analog apparently carries a dual effect on passive avoidance behavior.
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012153:Retention, Psychology / Q000187:drug effects
chemical_list: D010446:Peptide Fragments; C013765:Org 2766; D000324:Adrenocorticotropic Hormone; C011394:ACTH (4-10)