Shigeru Aonuma

Osteogenesis bioassay and immunohistochemical and radioisotopic studies of parotin, parotid gland extract, and subunit

Bioassay data support the hypothesis that the salivary gland participates in endocrine regulation of the development and maintenance of connective tissues. Epiphyseal cartilages become dystrophic in young growing rats after the resection of all major salivary glands. A subunit obtained from parotin, an extract of bovine parotid glands, contains the active agent for the presumed endocrine function of the salivary gland. Daily injections of 3 mg/rat of parotin or the subunit allow normal epiphyseal endochondral osteogenesis in salivary gland-deprived rats. The active agent appears to be secreted by the salivary acinar cells and resorbed through the striated ducts. Pancreatic islets and striated ducts of salivary glands share immunohistochemical activities for insulin, glucagon, and the subunit of parotin. Hyperglycemia and hypocholesterolemia occur in intact rats given 5 mg/day of parotin for 30 days. Together these data suggest endocrine functions of the salivary gland and possible interactions between the pancreatic islet and salivary gland.

Osteogenesis bioassay and immunohistochemical and radioisotopic studies of a subunit of parotin, a parotid gland extract

Bioassay data support the hypothesis that salivary glands participate in endocrine regulation of the development and maintenance of connective tissues. Resection of all three major salivary glands damages epiphyseal cartilages in young growing rats. A subunit obtained from parotin, an extract of bovine parotid glands, contains the active agent for the presumed endocrine function of salivary glands. Daily injections of 3 mg/rat of parotin or the subunit allow normal epiphyseal endochondral osteogenesis in salivary gland-deprived rats. The active agent appears to be secreted by the salivary acinar cells and resorbed through the striated ducts. Pancreatic islets and striated ducts of salivary glands share immunohistochemical activities for insulin, glucagon, and the subunit of parotin. Hyperglycemia and hypocholesterolemia occurred in intact rats given 1 to 5 mg/day of parotin for 30 days. These data together suggest endocrine function of the salivary glands and possible interactions between the pancreatic islets and salivary glands.

CHEMISTRY OF SALIVARY GLAND HORMONE

Publisher Summary This chapter describes the primary structure of AA-1 containing the complete amino acid sequence and the location and the proposed structure of carbohydrate moiety. AA-1 is a glycopeptides having a molecular weight of 9100, carbohydrate moiety, and 15 different kinds of amino acids that contain one methioninyl residue and no detectable prolinyl, cystinyl, or histidinyl residues. In an experiment described in the chapter, the presence of free amino acids in the thermolytic digests were in accord with reports that thermolysin cleaved both of phenylalanine in nerve growth factor and leucine in cytochrome, although the general susceptibility to hydrolysis by thermolysin required the absence of free amino and carboxyl groups in the immediate vicinity of the peptide bond to be hydrolyzed. The purified carbohydrate fraction was analyzed for amino sugar and neutral sugar compositions, and its structure was investigated by sequential enzymic digestion with exoglycosidases.

Studies on Gastric Acid Stimulating Effect of Tetragastrin

After administration of tritum labeled tetragastrin into rats, the distribution of 3Htetragastrin was studied. Radioactivity was found to be highest in duodenal mucosa and it was confirmed by radioautogram. In the stomach, radioactivity was low but it located in the mucosa. We also investigated gastric acid secreting effects of tetragastrin in the duodenum. Tetragastrin stimulated the secretion of gastric acid and this gastric acid secretion that responded to tetragastrin was reduced, when the duodenum was removed in Shay rat. However, boiled extract from duodenal mucosa removed after injection of tetragastrin examined by Ghosh and Schilds method had no effect to increase gastric acid secretion. (See pp. 527-,-531)

STUDIES ON POSTERIOR PITUITARY HORMONES I. EXTRACTION AND CHEMICAL PROPERTIES OF OXYTOCIC SUBSTANCE FROM URINE

1.No remarkable difference between the contents of oxytocic principle in posterior pituitary of male bovine and female was found.2. Oxytocic substance was extracted from human and rabbit urine.This substance was contained more in rabbit urine than in human urine.3.This oxytocic substance extracted from male urine had higher potency rather than that of female urine.4. Urinary oxytocic substance gave same properties as posterior pituitary extract in counter-current distribution, paper chromatography, electrophoresis and amino acid composition.

THE EFFECTS OF ACTH AND DEHYDROASCORBIC ACID ON THE SERUM AND URINARY URIC ACID LEVEL IN RABBITS

1. Intravenous injection of DHA (100mg) increased serum uric acid after 1hr., but injection of ACTH (10mg) had no effect on serum uric acid.2. Daily injections of DHA (100mg per day) gradually increased serum uric acid level only for the period of injections.3. Injection of DHA (100mg) and ACTH (5mg) apparently increased urinary uric acid excretion a day after injections.