Influence of beta-lipotropin fragments on responsiveness of rats to electric footshock.
Subcutaneous administration of graded doses of neuropeptides related to lipotropin (beta LPH) changed responsiveness of rats to electric footshock. gamma-Endorphin and related peptides increased the susceptibility of rats, whereas beta-endorphin induced a reversed effect. The enhanced responsiveness induced by DT gamma E, persisted for more than 24 hr and appeared to be of a central origin. Structure-activity relationship studies revealed that the sequence LPH 65-69 may contain the active core in this respect. An increased sensitivity to electric shock within one test procedure was observed with DT gamma E and alpha-endorphin. Prior experience with the test procedure diminished or abolished this effect of alpha-endorphin. It is suggested that beta-endorphin and its fragments play a physiological role in adaptive behavioral changes induced by peripheral stimuli.
D000661:Amphetamine / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004597:Electroshock; D006220:Haloperidol / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D009020:Morphine / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013329:Structure-Activity Relationship
D010446:Peptide Fragments; D009020:Morphine; D000661:Amphetamine; D006220:Haloperidol