CHRONIC ETHANOL ON MESSENGER-RNA LEVELS OF IP(3)R1, IP3 3-KINASE AND MGLUR1 IN MOUSE PURKINJE NEURONS

CHRONIC ethanol exposure is known to alter the polyphosphoinositide (p oly-PI) signaling pathway, although the exact sight of regulation is n ot well understood. In this study, C57B1/6J mice were given a control or an ethanol (6 g kg(-1) body wt) liquid diet by gastric intubation d aily for 4 weeks. Examination of levels of mRNA for type 1 inositol 1, 4,5-trisphosphate receptor (IP(3)R1), inositol 1,4,5-trisphosphate 3-k inase (IP3K) and metabotropic glutamate receptor 1 (mGluR1) in cerebel lar Purkinje neurons by in situ hybridization revealed significant dec reases in cellular levels of mRNA encoding both IP(3)R1 and mGluR1 in the ethanol-treated group compared with controls, but levels of IP3K m RNA were not altered. These results suggest that chronic ethanol consu mption selectively alters cellular mRNA in the poly-PI signaling pathw ay. The decrease in mRNA levels of mGluR1 and IP(3)R1 may be an import ant underlying mechanism towards explaining the alcohol-induced degene rative changes in the cerebellar Purkinje neurons.