Premium
Effect of Ethanol Administration and Withdrawal on Serotonin Receptor Subtypes and Receptor‐Mediated Phosphoinositide Hydrolysis in Rat Brain
Author(s) -
Pandey Subhash C.,
Piano Mariann R.,
Schwertz Dorie W.,
Davis John M.,
Pandey Ghanshyam N.
Publication year - 1992
Publication title -
alcoholism: clinical and experimental research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.267
H-Index - 153
eISSN - 1530-0277
pISSN - 0145-6008
DOI - 10.1111/j.1530-0277.1992.tb00706.x
Subject(s) - 5 ht receptor , receptor , serotonin , endocrinology , medicine , chemistry , agonist , adrenergic receptor , prazosin , biology , antagonist
The effect of short‐term (15 days) and long‐term (60 days) ethanol treatment and withdrawal on agonist‐stimulated phosphoinositide (PI) hydrolysis, serotonin receptor subtypes (5HT 1A and 5HT 2 ), and α 1 ‐adrenergic receptors were studied in rat cerebral cortex. Short‐term ethanol treatment had no significant effect on serotonin (5HT), norepinephrine (NE), and calcium ionophore (A23187)‐stimulated [ 3 H]‐inositol‐l‐phosphate ([ 3 H]‐IP 1 ) formation and 5‐HT 2 receptors as measured by 125 I‐lysergic acid diethylamide ( 125 I‐LSD) binding, in rat cerebral cortex. However, 15 days of ethanol treatment, followed by 24 hr of withdrawal resulted in a decrease in B max of 125 I‐LSD binding without significant change in K D1 as well as a decrease in 5HT‐stimulated [ 3 H].IP 1 formation in rat cerebral cortex. 5HT 1A and α 1 ‐adrenergic receptors were determined by using [ 3 H]‐8‐hydroxy‐2‐(di‐N‐propylamino)tetralin and [ 3 H]‐prazosin as radioligand, respectively. We also observed that long‐term ethanol treatment had no significant effect on B max and K D of 5HT 21 , 5HT 1A , and α 1 ‐ adrenergic receptors, as well as NE and A23187‐stimulated [ 3 H]‐IP 1 formation, but significantly decreased the 5HT‐stimulated [ 3 H]‐IP l formation in rat cerebral cortex. It is possible that a decrease in 5HT‐induced PI turnover after long‐term ethanol exposure may be due to a decrease in coupling of 5HT 2 receptors to G protein or PLC enzyme, whereas the decrease in 5HT‐induced PI turnover after withdrawal may be due to a decrease in functional 5HT 2 receptor number.