title: Adrenocorticotropic hormone fragment ACTH/MSH(4-10 can act as a discriminative stimulus in rats.
abstract: Five of eight male albino rats learned to discriminate the effects of ACTH/MSH(4-10) (100 micrograms/kg, SC) from those of saline vehicle in a food-reinforced T-maze task. Generalization tests showed that the ACTH/MSH(4-10) cue was dose related with an ED50 of approximately 68.0 micrograms/kg. These findings indicate that ACTH/MSH(4-10) has interoceptive stimulus properties discriminable to some animals, which might provide a useful model for studying the pharmacology of this neuroactive peptide. Moreover, since ACTH/MSH(4-10) induces effects similar to those of ACTH/MSH in the central nervous system but not hormonally, these data suggest that endogenous ACTH or MSH may also have interoceptive stimulus effects unrelated to peripheral endocrine activity.
authors.affiliation: Dorn Veterans' Administration Hospital, Columbia, SC 29201.
authors.forename: E E
authors.initials: EE
authors.lastname: Riddle
authors.forename: L L
authors.initials: LL
authors.lastname: Hernandez
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D004193:Discrimination Learning / Q000187:drug effects*; D005795:Generalization, Stimulus / Q000187:drug effects; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000494:pharmacology*; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D010446:Peptide Fragments; D000324:Adrenocorticotropic Hormone; D009074:Melanocyte-Stimulating Hormones; C011394:ACTH (4-10)