ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: Phosphoinositide turnover stimulated by 5-hy-droxytryptamine (5-HT) receptors in the intact rat brain was studied using an in vivo method. Phosphoinositides in the rat brain were prelabeled with [3H]inositol injected into the lateral cerebral ventricles. The rats were killed by microwave irradiation after 48 h and the contents in the frontal cortex of 3H-inositol phosphates, [3H]inositol-1-monophosphate ([3H]IP1), [3H]inositol-l,4-bisphosphate ([3H]IP2), and a mixture of [3H]inositol-l,4,5-trisphosphate and [3H]inositol-1,3,4-trisphosphate ([3H]IP3) were assayed by HPLC. Lithium treatment (10 mEq/kg, i.p., 2 h before) increased the content of[3H]IP1 and[3H]IP2. 5-Methoxy-N′,N-dimethyltryptamine (5-MeODMT) and quipazine, 5-HT agonists, significantly increased the amount of 3H-inositol phosphates under lithium pretreatment. The response to 5-MeODMT was inhibited by ritanserin, a 5-HT2 antagonist, but not by (—)-propranoloI, a 5-HT1 antagonist. These results suggest that phosphoinositide turnover in the rat frontal cortex in vivo is stimulated by 5-HT2 receptor activation. It is considered that this method will be useful for measurement of 5-HT2 receptor-stimulated phosphoinositide turnover in vivo to examine the in vivo effects of various psychotropic drugs such as antidepressants.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1989.tb07369.x
