John G. T. SNEYD

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1. 3':5'-Cyclic nucleotide phosphodiesterase activity was measured in homogenates prepared from epididymal fat-pads and isolated fat-cells incubated in the absence and presence of insulin. 2. Homogenates of insulin-treated tissues showed an increase in phosphodiesterase activity compared with controls. No effect of insulin was observed when the hormone was(More)
Rats from an inbred strain (NZR/Mh) were found to have high concentrations of glycogen in their livers, even after 24 h of starvation. Despite this, blood glucose concentrations were well maintained on starvation for up to 72 h. The primary defect is a deficiency of liver phosphorylase kinase, causing a lack of active glycogen phosphorylase, although total(More)
Cyclic 3′, 5′ nucleotide phosphodicsterase and adenyl cyclase were measured in homogenates prepared from isolated fat cells from obese (NZO/Bl) and normal mice. Young obese mice showed increased phosphodiesterase activity compared with controls. Older mice of both strains showed markedly diminished phosphodiesterase activity which, however, remained higher(More)
The adenosine-sensitive cyclic AMP phosphodiesterase of rat adipocytes was found to reside in the same subcellular fraction as the enzyme sensitive to insulin. There were several similarities between the action of adenosine and that of insulin on the enzyme. The action of adenosine on the phosphodiesterase is probably like that of insulin, both being(More)
A New Zealand strain of rats (NZR/Mh) is unable to mobilize liver glycogen due to a deficiency of phosphorylase b kinase. Affected homozygous rats (gsd/gsd) were used to assess the developmental relationship between lung glycogen loss and surfactant phospholipid and protein biosynthesis. Phosphorylase a and phosphorylase b kinase activities were negligible(More)