PT - JOURNAL ARTICLE AU - Matsuoka, Toshiyuki AU - Nishizaki, Tomoyuki AU - Sumino, Kimiaki TI - A Specific Inhibitory Action of Lithium on the 5-HT<sub>2c</sub>Receptor Expressed in <em>Xenopus laevis</em> Oocytes DP - 1997 Mar 01 TA - Molecular Pharmacology PG - 471--474 VI - 51 IP - 3 4099 - http://molpharm.aspetjournals.org/content/51/3/471.short 4100 - http://molpharm.aspetjournals.org/content/51/3/471.full SO - Mol Pharmacol1997 Mar 01; 51 AB - The effect of lithium on the phosphoinositide-signaling pathway was examined in 5-HT2C receptors, which are involved in phospholipase C stimulation, expressed in Xenopus laevisoocytes by voltage-clamp recording and assay of intracellular Ca2+ concentrations. Treatment with lithium for 60 sec after the initial application of 5-HT reduced Ca2+-dependent chloride currents in a dose-dependent manner (0.01–1 mm) and inhibited intracellular Ca2+release, whereas pretreatment with lithium or injection into oocytes had no effect. Additionally, treatment with lithium for more than 24 hr reduced 5-HT-evoked currents to a much lesser extent. In contrast, the currents through other phosphoinositide-dependent receptors, such as endogenous “serum” and muscarinic ACh receptors, were not affected or less affected by a short term or long term treatment with lithium, respectively. These results indicate that lithium may have a specific blocking effect on the 5-HT2C receptors and, in part, nonselectively act on the phosphoinositide metabolic pathway. The American Society for Pharmacology and Experimental Therapeutics