Biphasic secretory response of exocrine pancreas to feeding

By means of a newly developed device, secretory response of the exocrine pancreas to feeding was continuously recorded for 24 h in conscious dogs. It was then found that the postprandial secretory pattern of the pancreas was biphasic. The first peak of secretion, rich in enzymes, occurred 2.3 +/- 0.11 h after feeding and its secretory volume was 25.3 +/- 3.10 ml/h. After the first peak, pancreatic secretion decreased slightly, but started to increase again. At 10.8 +/- 0.31 h after feeding, the second peak of secretion occurred and this was 40.5 +/- 2.93 ml/h, significantly higher than the first peak secretion and the greatest in 1 day. The second peak secretion did not contain a higher concentration of enzymes, but was rich in bicarbonate. Approximately 16 h after feeding, pancreatic secretion returned to the basal level, which continued until the next meal. That water and bicarbonate secretion of the pancreas is the greatest at about the 11th postprandial h had never been reported before. The physiological role of the pancreatic secretion at that time is more likely to be related to the neutralization of acid entering from the stomach than to the digestion of food.

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Plasma secretin concentrations in fasting and postprandial states in dog.

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1979.236.5.e539 ◽

1979 ◽

Vol 236 (5) ◽

pp. E539 ◽

Cited By ~ 6

Author(s):

M S Kim ◽

K Y Lee ◽

W Y Chey

Keyword(s):

Pancreatic Secretion ◽

Physiological Role ◽

Fasting State ◽

Meat Meal ◽

Duodenal Ph ◽

The Mean ◽

Bicarbonate Output ◽

Marked Suppression ◽

Sustained Increase

In four dogs with a modified Herrara pancreatic fistula and gastric cannula and three dogs with two duodenal cannulas, ingestion of a meat meal resulted in a significant and sustained increase in the mean plasma immunoreactive secretin concentrations, from mean fasting levels of less than 10 pg/ml to 25--55 pg/ml. This increase in the plasma secretin concentration coincided with a marked increase in pancreatic bicarbonate output and frequent decreases in the mean proximal duodenal pH to less than 4.5 from the range of 6.5 in the fasting state. Intravenous administration of cimetidine, 150 mg, produced a marked suppression of postprandial increases in both pancreatic bicarbonate output and plasma secretin concentration. Moreover, the postprandial duodenal pH rarely reached below 5.0 after cimetidine administration. These studies indicate that plasma secretin concentration does increase significantly after a meal. The postprandial increase in plasma secretin concentration appears to depend on the gastric acid delivered in the proximal duodenum. A possible physiological role of secretin in the pancreatic secretion after a meal is indicated by these findings.

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Role of secretin and CCK in the stimulation of pancreatic secretion in conscious dogs. Effects of atropine and somatostatin

International Journal of Gastrointestinal Cancer ◽

10.1007/bf02788400 ◽

1987 ◽

Vol 2 (4) ◽

pp. 223-235

Author(s):

Stanislaw J. Konturek ◽

JanW Konturek ◽

Cornelis B. Lamers ◽

Janine Tasler ◽

Jan Bilski

Keyword(s):

Pancreatic Secretion ◽

Conscious Dogs ◽

Stimulation Of

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Impaired mucin synthesis and bicarbonate secretion in the colon of NHE8 knockout mice

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00146.2012 ◽

2012 ◽

Vol 303 (3) ◽

pp. G335-G343 ◽

Cited By ~ 29

Author(s):

Hua Xu ◽

Bo Zhang ◽

Jing Li ◽

Chunhui Wang ◽

Huacong Chen ◽

...

Keyword(s):

Embryonic Stem ◽

Physiological Role ◽

Normal Serum ◽

Sodium Absorption ◽

Bicarbonate Secretion ◽

Embryonic And Fetal Development ◽

Sodium Hydrogen Exchanger ◽

Important Player ◽

Normal Serum Sodium

Sodium/hydrogen exchanger 8 (NHE8), the newest member of the SLC9 family, is expressed at the apical membrane of the epithelial cells in the intestine and the kidney. Although NHE8 has been shown to be an important player for intestinal sodium absorption early in development, its physiological role in the intestine remains unclear. Here, we successfully created a NHE8 knockout (NHE8−/−) mouse model to study the function of this transporter in the intestinal tract. Embryonic stem cells containing interrupted NHE8 gene were injected into mouse blastocyst to produce NHE8+/− chimeras. NHE8−/− mice showed no lethality during embryonic and fetal development. These mice had normal serum sodium levels and no signs of diarrhea. Apically expressed NHE2 and NHE3 were increased in the small intestine of the NHE8−/− mice in compensation. The number of goblet cells and mucin (MUC)-positive cells in the colon was reduced in NHE8−/− mice along with mucosal pH, MUC2 expression as well as downregulated in adenoma (DRA) expression. Therefore, the role of NHE8 in the intestine involves both sodium absorption and bicarbonate secretion.

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The physiological role of histamine in the exocrine pancreas

Inflammation Research ◽

10.1007/s000110050156 ◽

1997 ◽

Vol 46 (5) ◽

pp. 159-165 ◽

Cited By ~ 11

Author(s):

J. Singh ◽

J. A. Pariente ◽

G. M. Salido

Keyword(s):

Exocrine Pancreas ◽

Physiological Role

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THE ROLE OF EXTRACELLULAR CALCIUM IN THE SECRETORY RESPONSE OF THE EXOCRINE PANCREAS TO SECRETIN AND FORSKOLIN

Biomedical Research ◽

10.2220/biomedres.8.233 ◽

1987 ◽

Vol 8 (4) ◽

pp. 233-240 ◽

Cited By ~ 1

Author(s):

TOMOKO YOSHIDA ◽

TOMIO KANNO

Keyword(s):

Exocrine Pancreas ◽

Extracellular Calcium ◽

Secretory Response

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An important role of endogenous insulin on exocrine pancreatic secretion in rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1990.258.2.g268 ◽

1990 ◽

Vol 258 (2) ◽

pp. G268-G274 ◽

Cited By ~ 7

Author(s):

K. Y. Lee ◽

L. Zhou ◽

X. S. Ren ◽

T. M. Chang ◽

W. Y. Chey

Keyword(s):

Pancreatic Secretion ◽

Physiological Role ◽

Rabbit Serum ◽

Normal Rabbit Serum ◽

Dependent Manner ◽

Exocrine Pancreatic Secretion ◽

Liquid Meal ◽

Amylase Output ◽

Endogenous Insulin

We have investigated a physiological role of endogenous insulin on exocrine pancreatic secretion stimulated by a liquid meal as well as exogenous secretin and cholecystokinin octapeptide (CCK-8) in conscious rats. Each rat was prepared with a chronic pancreatic fistula and an indwelling catheter in a jugular vein. Oral ingestion of a liquid meal (5 ml) resulted in significant increases in pancreatic secretion, including volume, bicarbonate, and amylase output, in these rats. A rabbit anti-insulin serum (1.0 ml) given intravenously completely blocked the postprandial exocrine pancreatic secretion, whereas a normal rabbit serum did not influence the pancreatic secretion in the same rats. When pancreatic secretion was stimulated by intravenous administration of both secretin and CCK-8 in three different doses, including 0.015, 0.03, and 0.06 clinical unit and microgram.kg-1.h-1, respectively, volume, bicarbonate, and amylase output increased significantly in a dose-dependent manner. This increase in pancreatic secretion was also completely blocked by a rabbit anti-insulin serum, whereas it was not influenced by a normal rabbit serum. The amount of the antiserum employed abolished the postprandial increases in plasma insulin concentration. We conclude that endogenous insulin plays an important role on the regulation of postprandial pancreatic secretion in rats. Furthermore, for the stimulatory action of the two intestinal hormones secretin and CCK-8 on the pancreatic exocrine secretion, endogenous insulin is need.

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Calcium and pancreatic secretion. I. Subcellular distribution of calcium and magnesium in the exocrine pancreas of the guinea pig.

The Journal of Cell Biology ◽

10.1083/jcb.65.1.88 ◽

1975 ◽

Vol 65 (1) ◽

pp. 88-102 ◽

Cited By ~ 71

Author(s):

F Clemente ◽

J Meldolesi

Keyword(s):

Guinea Pig ◽

Subcellular Distribution ◽

Pancreatic Secretion ◽

Exocrine Pancreas ◽

Acinar Cells ◽

Cell Fractionation ◽

Zymogen Granules ◽

Membrane Bound ◽

Calcium And Magnesium

The distribution of calcium and magnesium has been studied in the acinar cells of the pancreas of the guinea pig. Most of the magnesium was found to be associated with the rough microsomes (probably bound to the ribosomes) and with the postmicrosomal supernate. In contrast, calcium was distributed among all the particulate fractions, primarily the mitochondria, microsomes (especially smooth surfaced), zymogen granules, and the plasmalemma, and was low in the postmicrosomal supernate. Most of the calcium recovered in the particulate fractions was found to be membrane bound. The highest concentrations were found in the membranes of the zymogen granules and in the plasmalemma. By means of control experiments using -45Ca as the tracer, it was established that a considerable redistribution of calcium occurs during homogenization and cell fractionation. At least some of the resulting artifacts were estimated quantitatively and the data were corrected accordingly. The biochemical results were confirmed with the cytochemical antimonate technique carried out on the tissue as well as on isolated fractions. The role of calcium associated with the zymogen granules and with their limiting membranes is discussed in relation to the architecture of the granule and to the functionality of the pancreatic juice.

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A physiological role of peptide YY on exocrine pancreatic secretion in rats

Gastroenterology ◽

10.1016/0016-5085(93)90028-b ◽

1993 ◽

Vol 105 (1) ◽

pp. 208-215 ◽

Cited By ~ 58

Author(s):

Haiou Jin ◽

Lixing Cai ◽

Kaeyol Lee ◽

Ta-Ming Chang ◽

Ping Li ◽

...

Keyword(s):

Pancreatic Secretion ◽

Peptide Yy ◽

Physiological Role ◽

Exocrine Pancreatic Secretion

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Role of cholecystokinin in intestinal phase and meal-induced pancreatic secretion

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1989.257.5.g782 ◽

1989 ◽

Vol 257 (5) ◽

pp. G782-G790 ◽

Cited By ~ 3

Author(s):

W. E. Dale ◽

C. M. Turkelson ◽

T. E. Solomon

Keyword(s):

Sodium Oleate ◽

Pancreatic Secretion ◽

Plasma Concentrations ◽

Amylase Secretion ◽

Bicarbonate Secretion ◽

Lower Plasma ◽

Intestinal Phase ◽

Meat Meal ◽

Plasma Cholecystokinin

Amylase secretion and plasma cholecystokinin (CCK) were measured in dogs in the interdigestive state and after exogenous CCK-8 and CCK-39 (12.5 to 400 pmol.kg-1.h-1), intestinal sodium oleate, tryptophan plus phenylalanine, HCl (0.74, 2.2, 6.7, 20 mmol/h), and a meat meal (20 g/kg). Interdigestive plasma CCK did not vary, although amylase output showed periodic 15-fold increases. Plasma CCK increased linearly after doubling doses of CCK-8 and CCK-39; the slope of plasma CCK-39 vs. dose was 2.8 times steeper than that of CCK-8, suggesting a longer circulating half-life. At similar plasma concentrations, CCK-8 and CCK-39 were equipotent for stimulating pancreatic secretion. Sodium oleate and tryptophan plus phenylalanine significantly increased plasma CCK and amylase secretion in a load-dependent pattern and were equipotent for both effects. HCl stimulated bicarbonate secretion but not plasma CCK or amylase secretion. Food significantly increased plasma CCK and amylase secretion. Amylase responses to intestinal stimulants and food were significantly greater than to exogenous CCK at low plasma CCK levels. Maximal amylase responses to intestinal stimulants were similar to that after CCK-39 but occurred at 10-fold lower plasma CCK levels. These results indicate that CCK and other factors interact to regulate pancreatic responses to food and intestinal stimulants in dogs.

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