title: Intrinsic protein phosphorylation in synaptosomal plasma membrane fragments: a comparison of cerebral cortex tissue from several species, including human biopsy specimens.
abstract: Intrinsic protein phosphorylation was studied in synaptosomal membrane fragments made from cerebral cortex tissue taken from the following species: human (biopsy specimens), ox, rat, rabbit, guinea pig and mouse. Membrane fragments from all species exhibited a qualitatively similar range of protein acceptors phosphorylated by cyclic AMP-dependent protein kinase activity; contrary to a previous report, no evidence for cyclic GMP-dependent protein kinase activity was found in the human material. With the exception of membrane fragments prepared from ox brain, all the preparations exhibited the same range of Ca2+-dependent protein kinase activity. Ox brain obtained from a slaughterhouse yielded membranes containing no Ca2+-dependent protein kinase activity, but this may have been due to unavoidable postmortem losses.
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002417:Cattle; D002540:Cerebral Cortex / Q000378:metabolism*; D000242:Cyclic AMP / Q000494:pharmacology; D006152:Cyclic GMP / Q000494:pharmacology; D006168:Guinea Pigs; D006801:Humans; D051379:Mice; D008970:Molecular Weight; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D013045:Species Specificity; D013570:Synaptic Membranes / Q000378:metabolism*
chemical_list: D010750:Phosphoproteins; D000242:Cyclic AMP; D011494:Protein Kinases; D006152:Cyclic GMP; D002118:Calcium