Behavioral alterations induced by substance P, bombesin, and related peptides in mice.
Bombesin, substance P and several structurally related peptides cause excessive grooming behavior after intracerebroventricular injection in mice. The present study describes the behavioral characteristics of these effects after acute administration. Substance P caused an elevation of grooming behavior which was short-lasting (less than 15 minutes), while bombesin induced both grooming and scratching behavior with a duration of action of about 2.5 hours. After repeated injections of high doses of either bombesin or a metabolically stable substance P analog, no tolerance-formation to these peptide-induced effects could be observed. Morphine partially antagonized bombesin-induced behaviors at a dose of 7.5 mg/kg subcutaneously while the same dose did not attentuate substance P-induced grooming. These results suggest that the behavioral changes induced by substance P and bombesin are mediated by distinct mechanisms. The lack of tolerance formation, together with the partial antagonism by morphine, suggests that the bombesin-induced behaviors may be related to a stimulation of nociceptive mechanisms.
D000818:Animals; D001839:Bombesin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D004361:Drug Tolerance; D006120:Grooming / Q000187:drug effects*; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects*; D013239:Stereotyped Behavior / Q000187:drug effects*; D013329:Structure-Activity Relationship; D013373:Substance P / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology*; D013997:Time Factors
D013373:Substance P; D001839:Bombesin