Chronic alcoholization alters the expression of 5-HT1A and 5-HT1B receptor subtypes in rat brain

Serotonin 1A receptor autoradiography during alcohol-withdrawal kindling

“…The results of the single episode experiment of the present investigation are in agreement with behavioural studies showing tolerance to 8-OH-DPAT induced ßat body posture following chronic alcohol intoxication and with autoradiographic ligand binding studies in which chronic alcohol intoxication led to a focal downregulation of [ 3 H]-8-OH-DPAT binding sites in frontal cortex, entorhinal cortex and hippocampus (Nevo et al 1995). In Nevo et al (1995) the concentration of the mRNA which codes for the 5-HT 1a receptor was decreased in hippocampus, suggesting that the downregulation of 5-HT 1a binding sites was due to a decreased 5-HT 1a protein synthesis.…”

“…As the severity of the withdrawal reaction in the rat is much higher following 4 days of severe alcohol intoxication than after 2 days of severe alcohol intoxication (Majchrowicz and Hunt 1976), the negative results of the membrane binding studies in the animals exposed to 2 days of alcohol intoxication may theoretically be related to the relatively mild degree of physical alcohol dependence which occurred in these animals. More research, however, is needed to elucidate the discrepancies between [ 3 H]-8-OH-DPAT binding in autoradiographic and membrane binding assays following chronic alcohol intoxication found in both the present investigation and (Nevo et al 1995).…”

“…In Nevo et al (1995) the concentration of the mRNA which codes for the 5-HT 1a receptor was decreased in hippocampus, suggesting that the downregulation of 5-HT 1a binding sites was due to a decreased 5-HT 1a protein synthesis. In disagreement with the focal downregulation of 5-HT 1a binding sites found by Nevo et al (1995), these researchers failed to detect alcohol-induced alterations in [ 3 H]-8-OH-DPAT binding when the receptor binding assays were performed on brain membranes. These Þndings, however, are in agreement with the inconsistency of the results from the autoradiographic and membrane binding assays performed on the animals from the single episode experiment exposed to 2 days of alcohol intoxication in the current study.…”

5-HT1A agonists: alcohol drinking in rats and squirrel monkeys

“…The rats drank reliably when tested four to five times per week. Differences in the amount of alcohol exposure could be a factor in the differential effects of 5-HT 1A agonists as chronic daily alcohol treatments of 4 g/kg IP or 14 g/kg in liquid diet have been found to alter 5-HT 1A receptor expression and sensitivity (Nevo et al 1995;Esteban et al 2002). In this case, the average alcohol intake of 0.56 g/kg consumed by rats and 0.49 g/kg consumed by monkeys were both well below chronic levels and unlikely to have induced neurological changes extensive enough to be responsible for the large differences in findings between the species.…”

Effects of Chronic Ethanol Consumption and Aging on 5‐HT2A Receptors and 5‐HT Reuptake Sites

“…Chronic ethanol consumption also blunts the normal age-related increase in 5 -H W 5-HT in the ventral tegmental area, substantia nigra, and ventral pallid~m.,~ Chronic ethanol exposure increases the concentration of 5-HTI, receptors in the dorsal raphe and decreases it in the hippocampus and cortex. 36 Ethanol consumption, ethanol preference, and ethanolreinforced behavior are affected by drugs targeted at the serotonergic system. Treatment with 5-HT, antagonists, such as ritanserin, amperoxide, and risperidone, reduce ethanol craving, suppress alcohol preference, and prevent r e l a p~e .~"~ 5-HT, and 5-HT3 receptor antagonists decrease ethanol drinking; 5-HT3 antagonists also decrease ethanol-reinforced beha~ior.~' 5-HT, receptor antagonists may reduce ethanol consumption by inhibiting alcoholinduced firing.42…”