The combined action of insulin and phlorizin on transport and metabolism of sugars and nucleotide turnover in the isolated rat diaphragm.

The combined effects of insulin and phlorizin have been analyzed on two parameters of insulin stimulation in the surviving rat diaphragm : transport and metabolism of sugars, turnover of the phosphate groups of mononucleotides. Phlorizin (c mM) inhibits glucose transport both in the presence and absence of insulin and displays a small additional inhibitory effect on glycogen biosynthesis; with the non metabolizable glucose anlogue 3-O-methyl-D-glucose transport inhibition is demonstrated solely in the presence of insulin. No correlation is demonstrated between the rates of sugar transport, which are strongly phlorizin-sensitive, and the rates of nucleotide turnover, which show no such sensitivity.