ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: Long-term ethanol exposure is known to inhibit bradykinin-stimulated phosphoinositide hydrolysis in cultures of neuroblastoma × glioma 108–15 cells. In the present study, [3H]bradykinin binding, GTP-binding protein function, and phospholipase C activity were assayed in cells grown for 4 days in 100 mM ethanol with the aim of elucidating the molecular target of ethanol on signal transduction coupled to inositol trisphosphate and diacylglycerol formation. Ethanol exposure reduced guanosine 5′-O-(3-thiotriphosphate) [GTP(S)]- and, to a lesser extent, NaF/AlCl3-stimulated phosphoinositide hydrolysis, whereas it had no effect on the enzymatic activity of a phosphatidylinositol 4,5-bisphosphate-specific phospholipase C. [3H]Bradykinin binding in the absence of GTP(S) was not influenced by ethanol exposure. However, the reduction in [3H]bradykinin binding seen in control cells after addition of GTP analogue was inhibited in cells grown in ethanol-containing medium. The results indicate that long-term ethanol exposure exerts its effects on receptor-stimulated phosphoinositide hydrolysis primarily at the level of the GTP-binding protein.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1991.tb03461.x
