Exocrine Pancreatic Physiology

Abstract

Japanese researchers have contributed to the development of various areas of pancreatic physiology such as hormonal and neural regulation of pancreatic exocrine secretion, effect of nutrients on the exocrine pancreas, and stimulus-secretion coupling in the exocrine pancreas. Among them, we selected three fruitful areas and reviewed them. These are in vitro experiment with the perfusion of the isolated rat pancreas, research related to the cholecystokinin (CCK)-releasing factor of pancreatic acinar cell origin (monitor peptide), and development and characterization of two genetically diabetic rats: WBN/Kob and OLETF (Otsuka Long-Evans Tokushima fatty) rats. PERFUSION OF ISOLATED PANCREASKanno (1) developed an elegant and fine method of perfusion of the rat isolated pancreas. In his study, the inlet of the vascular perfusion was the superior mesenteric artery, and the outlet was the portal vein. The common duct was constantly flushed. The inlet of perfusion of the common duct was the hepatic end of the duct, and the outlet was the duodenal end. This method was further modified to allow more effective perfusion of the vascuSummary: Exocrine pancreatic physiology has been actively investigated in Japan during the past 30 years. We selected three areas and reviewed them for this article. The selected areas are perfusion of the isolated pancreas, cholecystokinin (CCK)-releasing factor from pancreatic juice (monitor peptide), ~ 265 and genetically diabetic rats. The aim of this article is to present a brief overview of the selected areas of exocrine pancreatic physiology in Japan so that future research can be productively directed. Key Words: Exocrine pancreatic physiologyCholecystokinin-releasing factor-Genetically diabetic rats. lar system and simultaneous measuring of the flow rate of pancreatic juice ( 2 ) . The inlets of vascular perfusion were both the superior mesenteric artery and the celiac artery, whereas the outlet was the portal vein. During part of the experiment, the hepatic end of the common duct was ligated, and the pancreatic juice collected from the duodenal end after cannulation with a stainless steel tube (Fig. 1). By using this system of perfusion of the isolated pancreas, Kanno et al.(3) demonstrated that addition of exogenous insulin to the perfusate potentiates the action of CCK to increase both pancreatic-juice flow and amylase release and that raising the glucose concentration in the perfusate potentiates the CCK-induced exocrine secretary response through an increase in endogenous insulin release (Fig. 2 ) . Kanno et al. wrote many articles on the effects of hormones (3-5) and on other factors (2,619) on stimulus-secretion coupling in the exocrine perfused pancreas. Otsuki et al. (19) isolated and perfused rat pancreas according to the technique of Kanno with slight modifications. They measured not only pancreatic-juice flow and amylase output but also insulin (and glucagon) in the portal effluent. Eventually they studied simultaneously both the exocrine and endocrine responses in perfused i...

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Risk factors for pancreatic cancer: underlying mechanisms and potential targets

“…The exocrine pancreas is composed of both acinar and ductal cells; acinar cells (or acini) are responsible for synthesis, storage and secretion of both active (amylase, lipase) and inactive enzymes (zymogens; trypsinogen) (Ogami and Otsuki, 1998). Over 100 years ago it was first documented that the hormone secretin could stimulate pancreatic secretion.…”

“…This results in release of pancreatic enzymes into the small intestine. These normal physiological responses can be altered by many factors that can ultimately lead to pathological responses and development of pancreatitis and pancreatic cancer (Bayliss and Starling, 1902; Ogami and Otsuki, 1998; Weiss et al, 2008). This review will focus on common pathways that link the progression from acute to chronic pancreatitis (CP) and finally pancreatic cancer.…”

Risk Factors for Pancreatic Cancer: Underlying Mechanisms and Potential Targets

“…The exocrine pancreas is composed of both acinar and ductal cells; acinar cells (or acini) are responsible for synthesis, storage and secretion of both active (amylase, lipase) and inactive enzymes (zymogens; trypsinogen) (Ogami and Otsuki, 1998). Over 100 years ago it was first documented that the hormone secretin could stimulate pancreatic secretion.…”

“…This results in release of pancreatic enzymes into the small intestine. These normal physiological responses can be altered by many factors that can ultimately lead to pathological responses and development of pancreatitis and pancreatic cancer (Bayliss and Starling, 1902;Ogami and Otsuki, 1998;Weiss et al, 2008). This review will focus on common pathways that link the progression from acute to chronic pancreatitis (CP) and finally pancreatic cancer.…”