Metabolism of phosphorus in the supersensitive submaxillary gland of the cat

¹ Department of Pharmacology, University of Kansas Medical Center, Kansas City, Kansas, and Department of Biochemistry, Tulane University School of Medicine, New Orleans, Louisiana

We have used the supersensitive submaxillary gland of the cat to investigate the relationship between secretory phenomena and phosphorus metabolism, in vivo. Supersensitivity was produced by surgical removal of a 1 cm section of the chorda tympani nerve or by chronic administration (15 days, s.c.) of 1, 1-diphenyl-4-N-piperidinobutyramide (Hö 9980). After subcutaneous injection of radiophosphorus, secretion was induced by administration of epinephrine or acetylcholine over a 2-hr experimental period. Analyses for phosphorus and radioactivity on the different phosphorus-containing fractions have shown that there was an increase in the specific activity of the phosphatido-peptide and phospholipid fractions obtained from the supersensitive gland. No increase was apparent in the radioactivity in the total acid-soluble or 7-min hydrolyzable fractions. The increase in metabolic activity of the phosphatido-peptide and phospholipid fractions was found to be blocked when atropine or dihydroergotamine were used to inhibit secretion. We interpret our findings as supporting evidence for the participation of these two fractions in secretion of saliva in a manner not yet understood.