Effects of chronic cocaine administration on the serotonergic system in the rat brain.
Male Sprague-Dawley rats received injections of cocaine (20 mg/kg/dose, IP) every 12 h for 14 days and were sacrificed on the 15th day. The chronic cocaine treatment caused an increase in the levels of serotonin [5-hydroxytryptamine (5-HT)] and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the hippocampus. 5-HIAA levels in the frontal cortex were also increased, but 5-HT levels were unaltered by the chronic cocaine treatment. Similarly, striatal levels of 5-HT and 5-HIAA were unchanged by repeated administration of cocaine. Chronic cocaine administration did not alter the density of [3H]8-OH(DPAT), [3H]mesulergine, or [3H]ketanserin binding in the hippocampus, choroid plexus, and frontal cortex, respectively. Furthermore, repeated injection of cocaine did not alter serotonergic-mediated inhibition of adenylate cyclase activity. Thus, repeated administration of cocaine causes region-specific alterations in 5-HT levels but does not change the properties of the 5-HT1A, 5-HT1C, or 5-HT2 receptors.
Johnson
R G
RG
Department of Pharmacology and Therapeutics, SUNY at Buffalo 14214.
Fiorella
D
D
Rabin
R A
RA
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000493:pharmacokinetics; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D000978:Antiparkinson Agents / Q000493:pharmacokinetics; D001921:Brain / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D001923:Brain Chemistry / Q000187:drug effects; D003042:Cocaine / Q000494:pharmacology*; D004873:Ergolines / Q000493:pharmacokinetics; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D007650:Ketanserin / Q000493:pharmacokinetics; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011985:Receptors, Serotonin / Q000187:drug effects; D012701:Serotonin / Q000502:physiology*
D000978:Antiparkinson Agents; D004873:Ergolines; D009419:Nerve Tissue Proteins; D011985:Receptors, Serotonin; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D007650:Ketanserin; D000262:Adenylyl Cyclases; D003042:Cocaine; C031649:mesulergine