Effects of GABA receptor blockade on stimulation-induced feeding and self-stimulation.
Frequency thresholds for eating elicited by electrical stimulation of the lateral hypothalamus of rats decreased in a dose-dependent manner after intraperitoneal (IP) administration of picrotoxin, a gamma-aminobutyric acid (GABA) antagonist that blocks GABA-mediated synaptic inhibition. Strychnine IP, a glycine antagonist that blocks glycine-mediated synaptic inhibition, had no effect. By contrast, frequency thresholds for self-stimulation at the same electrode site significantly increased after picrotoxin. Again, strychnine had no effect. These findings indicate that GABAergic mechanisms are involved in both electrically-elicited feeding and self-stimulation. They also suggest a dissociation of the neural substrates which subserve these behaviors.
D000818:Animals; D004435:Eating / Q000187:drug effects; D004558:Electric Stimulation; D018756:GABA Antagonists; D007031:Hypothalamus / Q000502:physiology*; D008297:Male; D010852:Picrotoxin / Q000494:pharmacology*; D051381:Rats; D012653:Self Stimulation / Q000187:drug effects*; D013331:Strychnine / Q000494:pharmacology
D018756:GABA Antagonists; D010852:Picrotoxin; D013331:Strychnine