Ritanserin and voluntary alcohol intake in rats.
In a previous study (Rammsayer & Vogel, 1991), rats selectively bred for high and low catecholamine responses to stress showed a selective response to the 5-HT2 receptor blocker ritanserin. However, it remained unclear whether selective breeding resulted in a decrease in 5-HT responsivity, as suggested by the lack of an effect in high stress responding rats, or in an increase in 5-HT responsivity, as suggested by ritanserin-induced reduction in alcohol intake in low-responding rats. To answer this question, nonselectively bred rats were forced to drink a 5% alcohol solution for 10 days. For the subsequent six days, animals were injected subcutaneously with 2.5 mg/kg/2 ml ritanserin or vehicle only, and both a 5% solution of alcohol and water were presented to the animals. Ritanserin neither affected alcohol nor total fluid intake suggesting that in the general population of N/NIH (Hansen) rats as well as in rats of the same strain selectively bred for high catecholamine responses, mesolimbic dopaminergic activity is not effectively modulated by specific blockade of 5-HT2 receptors. However, a very pronounced ritanserin induced difference in daily water intake between nonbred male and female rats became evident.
Rammsayer
T
T
Department of Psychology, University of Giessen, Germany.
Vogel
W H
WH
D000428:Alcohol Drinking / Q000523:psychology*; D000818:Animals; D004326:Drinking / Q000187:drug effects; D005260:Female; D008297:Male; D051381:Rats; D016713:Ritanserin / Q000494:pharmacology*; D012727:Sex Characteristics
D016713:Ritanserin