Cholecystokinin and bombesin inhibit ethanol and food intake in rats selectively bred for ethanol sensitivity.
Cholecystokinin octapeptide (CCK-8) and bombesin tetradecapeptide (BBS-14) are brain-gut neuropeptides shown to inhibit intake and choice of alcohol solutions and foods in a variety of species. Recently, Draski and colleagues selectively bred strains descended from N/Nih outbred Norway rats that differ in sleep time after injection of ethanol. The intake of 5% w/v ethanol, food, and water was measured in these rats with high, low, and control alcohol sensitivity (HAS, LAS, and CAS), after intraperitoneal injection of randomized sequences of doses of CCK-8 or BBS-14 (0-8 micrograms/kg). During baseline adaptation to water deprivation-induced consumption of alcohol, LAS rats consumed reliably more ethanol than HAS or CAS rats. Injection of CCK-8 or BBS-14 significantly and equivalently suppressed intake of ethanol and food at 30 min after presentation in each group of rats. Water intake and food intake at 30-60 min following alcohol access was not affected by prior injection of either neuropeptide. Large differences in alcohol neurosensitivity (HAS > CAS > LAS) were observed in these rats' resting behavior for 1 hr after intraperitoneal injection of 1 g/kg of ethanol. These selectively bred alcohol neurosensitivity differences cannot be explained by corresponding differences in sensitivity to the inhibitory behavioral effects of CCK-8 or BBS-14. However, differences in alcohol intake and resting behavior do correspond to artificially selected sensitivities to ethanol's hypnotic effect.
Kulkosky
P J
PJ
Department of Psychology, University of Southern Colorado, Pueblo 81001-4901.
Clayborne
Y J
YJ
Sandoval
S L
SL
D000428:Alcohol Drinking / Q000503:physiopathology*; D000818:Animals; D001143:Arousal / Q000187:drug effects / Q000502:physiology; D001839:Bombesin / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D004326:Drinking / Q000187:drug effects* / Q000502:physiology; D004435:Eating / Q000187:drug effects* / Q000502:physiology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012844:Sincalide / Q000494:pharmacology*
D012844:Sincalide; D001839:Bombesin