Influences of housing conditions and ethanol intake on binding characteristics of D2, 5-HT1A, and benzodiazepine receptors of rats.
The effects of different housing conditions and ethanol treatment (6 vol % in the drinking water) on the in vitro binding characteristics of striatal dopaminergic D2 ([3H]spiperone), hippocampal serotonergic 5-HT1A ([3H]8-OH-DPAT), and cortical benzodiazepine ([3H]flunitrazepam) receptors have been examined. Social deprivation due to contact caging, short- (1 day) and long-term isolation (5 weeks) yielded a significant decrease of striatal D2 receptor density with the greatest decrease after long-term isolation (-21% Bmax) without changes of Kd in comparison to group animals. The effect of ethanol on striatal D2 receptor density depended on the housing conditions. Whereas ethanol treatment reduced receptor density of group animals (down to 88%), chronic exposure to ethanol under long-term isolation elicited no significant alteration of D2 receptor density compared with group animals. Different housing and ethanol treatment had no effect on 5-HT1A receptor affinity and density. Alterations of benzodiazepine receptor density were not found, but social deprivation as well as ethanol treatment of group animals caused an increased affinity of [3H]flunitrazepam (reduced Kd value). These results indicate that different housing conditions of adult rats evoked significant alterations in D2 and benzodiazepine receptor binding assays, which were modified by ethanol treatment in the case of striatal D2 receptor density.
Rilke
O
O
AG Neurobiologie, Klinik für Psychiatrie, TU Dresden, Germany.
May
T
T
Oehler
J
J
Wolffgramm
J
J
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000378:metabolism; D000428:Alcohol Drinking / Q000378:metabolism*; D000818:Animals; D005445:Flunitrazepam / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D007700:Kinetics; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D017448:Receptors, Dopamine D2 / Q000378:metabolism / Q000502:physiology*; D011963:Receptors, GABA-A / Q000378:metabolism / Q000502:physiology*; D011985:Receptors, Serotonin / Q000378:metabolism / Q000502:physiology*; D012934:Social Isolation; D013134:Spiperone / Q000378:metabolism
D017448:Receptors, Dopamine D2; D011963:Receptors, GABA-A; D011985:Receptors, Serotonin; D013134:Spiperone; D005445:Flunitrazepam; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin