1. Paired iris smooth muscles from rabbits were incubated for 30 min at 37 degrees C in an iso-osmotic salt medium containg glucose, inositol, cytidine and [32P]phosphate. 2. One of the pair was then incubated at 37 degrees C for 10 min in unlabelled medium containing 10mM-2-deoxyglucose and the other was incubated in the presence of acetylcholine plus eserine (0.05mM each). 2-Deoxyglucose, whi...

The regulatory molecule, cyclic adenosine 3':5'-monophosphate (cAMP), can inhibit cell proliferation, reverse the neoplastic phenotype, and promote tumor regression. Since the biological effects of cAMP are mediated by an activation of protein kinase enzymes, the interaction of cAMP with the regulatory subunits of type I and II isozymes (Ri and RN)was studied in normal and neoplastic tissues. R...

Human platelets incubated with [32P]Pi and [3H]arachidonate were transferred to a Pi-free Tyrode's solution by gel filtration. The labile phosphoryl groups of ATP and ADP as well as Pi in the metabolic pool of these platelets had equal specific radioactivity which was identical to that of[32P]phosphatidate formed during treatment of the cells with thrombin for 5 min. Therefore, the 32P radioact...

Human erythrocyte membranes were incubated with a low concentration of terminally labeled ATP with the aim of detecting a phosphorylated intermediate of adenosine triphosphatase activity. A large portion of material labeled briefly at 37’ turned over and had properties consistent with participation in sodium ion-stimulated ATPase activity, including the following: (a) magnesium ions present, ad...

Rat liver glucocorticoid-receptor complex (GRc) was purified 2000-fold by a combination of methods including (NH4)2SO4-fractionation and phosphocellulose and DNA-cellulose chromatography. The purified glucocorticoid receptor preparation contained a major peptide of Mr = 90,000 and the GRc sedimented as 4 S in 5-20% sucrose gradients. An additional peptide of Mr = 45,000 (45K) was also observed....

Upon stimulation with serotonin of washed human platelets prelabeled with [32P]orthophosphate, we found an approximately 250% increase in [32P]phosphatidic acid (PA) formation, a small decrease in [32P]phosphatidylinositol 4,5-bisphosphate, and a concomitant increase in [32P]phosphatidylinositol 4-phosphate. Using [3H]arachidonate for prelabeling, [3H]diacylglycerol accumulated transiently at 1...

We have investigated the effects of insulin and motor denervation on the phosphorylation of glycogen synthase in skeletal muscle. Rat epitrochlearis muscles were denervated in vivo 3 days before the contralateral and denervated muscles were incubated in vitro with 32Pi to label sites in glycogen synthase. The 32P-labeled synthase was rapidly immunoprecipitated from extracts under conditions whi...

Addition of iron and aluminum compounds has become an increasingly popular method to regulate phosphorus eutrophication in lakes and reservoirs. It has been proposed that ferric chloride addition to agricultural runoff entering the northern Everglades could provide a means for enhancing natural mechanisms of phosphorus removal from the wetland. In this study we added ferric chloride to Everglad...

We have studied the effects of adenosine 3':5'-monophosphate (cAMP)-dependent protein kinase on the phosphorylative and functional modification of bovine adrenal tyrosine hydroxylase. Incubation of partially purified tyrosine hydroxylase with cAMP-dependent protein kinase in the presence of [gamma32P]ATP and 5 micron cAMP led to a 3- to 5-fold activation of tyrosine hydroxylase and to incorpora...

We have studied the effects of adenosine 3’:5’-monophosphate (CAMP)-dependent protein kinase on the phosphorylative and functional modification of bovine adrenal tyrosine hydroxylase. Incubation of partially purified tyrosine hydroxylase with CAMP-dependent protein kinase in the presence of [y-32P]ATP and 5 pM CAMP led to a 3to B-fold activation of tyrosine hydroxylase and to incorporation of [...