Article date: 1988/5/1
PubMed ID: 2457361
Journal name: Behavioral and neural biology (ISSN: 0163-1047)
The effects of injections of the neuropeptide substance P or the GABA agonist muscimol on performance of a step-down inhibitory avoidance task were examined. Immediately after the training trial, rats with chronically implanted cannulas were injected with 100 or 10 ng of substance P or 500 or 50 ng of muscimol into the region of the nucleus basalis magnocellularis. Control groups included vehicle-injected rats, a sham-operated group, a substance P 5-h delay group, and a substance P no-footshock group. Rats injected with 100 ng of substance P exhibited longer step-down latencies when tested 24 h later than did vehicle-injected rats. The retention latencies for rats in the substance P 5-h delay group did not differ from those of vehicle-injected animals, indicating that proactive effects on performance were not responsible for the effect. In contrast to injections of SP, injections of 500 or 50 ng of muscimol disrupted performance. However, in the absence of a delayed-injection control group, proactive effects cannot be ruled out.
Author List: Nagel J A, Huston J P
Publication Types: Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Muscimol; Substance P;
Mesh terms: Animals; Avoidance Learning/physiology; Basal Ganglia/drug effects; Male; Muscimol/pharmacology; Rats; Rats, Inbred Strains; Substance P/pharmacology;