Ethanol Has No Effect on CAMP‐Dependent Protein Kinase‐, Protein Kinase C‐, or Ca2+‐Calmodulin‐Dependent Protein Kinase II‐Stimulated Phosphorylation of Highly Purified Substrates in Vitro

The actions of ethanol on kinase stimulated phosphorylation were examined using highly purified protein kinases and a variety of purified substrates. Ethanol (25‐200 mm) failed to alter the phos phorylation of histone Ila and histone Ills by CAMP‐dependent protein kinase (PKA) and protein kinase C (PKC), respectively. Moreover, ethanol (25‐200 mm) did not affect the phosphorylation of synapsin I by Ca^2+‐celmodulin‐dependent protein kinase II (CAM kinase 11). Finally, neither PKA nor PKC stimulated phosphorylation of the GABAa receptor (GABA_A‐R) was modulated by ethanol at any con centration of ethanol tested. These results suggest that ethanol, in pharmacological concentrations, has no direct actions on the ability of these kinases to catalyze the phosphorylation of specific substrate proteins. In particular, ethanol does not appear to directly influence GABA_A‐R phorphorylation by either PKA or PKC.