Regulation of Pancreatic α-Amylase in the Neonatal Mouse

Abstract

The decrease in specific activity of mouse pancreatic α-amylase occurring at parturition is associated with changes in the morphological fine structure of the acinar cells, as evidenced by a decrease in the number of zymogen granules per cell and an increase in the rough endoplasmic reticulum. Following parturition there is a rapid increase in the synthesis of both amylase and total protein, with a selective increase in amylase synthesis during the first 24 hours. Metabolic requirements for in vitro secretion of amylase by the neonatal mouse pancreas were also studied; findings support existing evidence that fatty acids are the main oxidizable substrate of the acinar cell.

Development of Secretory Function in Rat Parotid Gland

“…Concentrations of catecholamines were optimal for stimulation of secretion and increased cyclic A M P levels in mature tissues as verified in previous studies (1 1,12,20). At the end of the incubation period, the medium was removed and frozen for subsequent determination of protein content and amylase activity.…”

“…Similarly, in studies of secretory function in developing pancreas, other workers (1,14) have shown an incremental response to carbamylcholine stimulation from fetal day 1 3 to the third day of life. In their experiments and others (7), however, ontogeny of receptors was not studied; and no such data are yet available for the parotid gland.…”

Amino Acid Transport in the Exocrine Pancreas. IV. Do Glucagon or Insulin Mediate the in Vivo Effect of Caerulein on Amino Acid Transport and Incorporation?

“…The physiological media tor for the in vivo hormone effects remains to be identified. Interes• tingly, in the newborn pancreas insulin together with glucose were found obligatory for normal func• tion (Albritton, Koops, Hurwitz and Kretchmer 1973;Cheneval and Johnstone 1976). This could indicate that exocrine cells respond directIy to insu• lin and eventually express insulin receptors only during growth and development and later only uno der pathological conditions.…”