Genetic differences in ethanol drinking of the rat following injection of 6-OHDA, 5,6-DHT or 5,7-DHT into the cerebral ventricles.
The preference characteristics for ethanol of four different strains of rats were determined in a two-choice situation by offering water and ethanol in a concentration which was increased from 3 to 30% over a 12-day test sequence. Using stereotaxic procedures, 50 mug 5,6-dihydroxytryptamine (5,6-DHT), 200 mug 6-hydroxydopamine (6-OHDA) or 100 mug 5,7-dihydroxytryptamine (5,7-DHT) were then injected acutely into the lateral cerebral ventricle in a 20 mul volume. Rats of the Sprague-Dawley strain increased their ethanol preference following the lesioning of the serotonergic system by 5,6-DHT, whereas similar destruction of catecholaminergic neurons by 6-OHDA markedly suppressed ethanol intake; Long-Evans rats displayed a similar trend in ethanol drinking patterns. However, animals of the Holtzman strain manifested the increased drinking after 5,6-DHT, but showed no suppression of drinking following 6-OHDA. The preference of rats of the Wistar strain was unaffected by 5,6-DHT but attenuated by 6-OHDA. 5,7-DHT had little or no effect on ethanol consumption in any of these strains. These findings thus suggest that genetic factors are an important determinant in an animal's response to a drug that affects 5-HT or NE systems in the brain, particularly when ethanol selection is investigated.
D015115:5,6-Dihydroxytryptamine / Q000008:administration & dosage / Q000494:pharmacology*; D000428:Alcohol Drinking; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D003891:Desipramine / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism; D005247:Feeding Behavior / Q000187:drug effects; D005824:Genetics, Behavioral; D006892:Hydroxydopamines / Q000008:administration & dosage / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D010293:Pargyline / Q000494:pharmacology; D051381:Rats / Q000502:physiology*; D012701:Serotonin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D013045:Species Specificity; D014363:Tryptamines / Q000494:pharmacology*
D006892:Hydroxydopamines; D014363:Tryptamines; D012701:Serotonin; D010293:Pargyline; D003891:Desipramine; D004298:Dopamine; D015115:5,6-Dihydroxytryptamine; D009638:Norepinephrine