Korean J Physiol Pharmacol.  1998 Apr;2(2):185-192.

A role of endogenous somatostatin in exocrine secretion induced by intrapancreatic cholinergic activation

• Park HS
• Park IS
• Kwon HY
• Lee YL
• Park HJ

Abstract

A role of endogenous somatostatin in pancreatic exocrine secretion induced by intrapancreatic cholinergic activation was studied in the isolated rat pancreas perfused with modified Krebs-Henseleit solution. Intrapancreatic neurons were activated by electrical field stimulation (EFS: 15 V, 2 msec and 8 Hz). Pancreatic exocrine secretion, including volume flow and amylase output, and release of somatostatin from the pancreas were respectively determined. Somatostatin cells in the islet were stained with an immunoperoxidase method. EFS significantly increased pancreatic volume flow and amylase output, which were reduced by atropine by 59% and 78%, respectively. Intraarterial infusion of either pertussis toxin or a somatostatin antagonist resulted in a further increase in the EFS-evoked pancreatic secretion. EFS also further elevated exocrine secretion in the pancreas treated with cysteamine, which was completely restored by intraarterial infusion of somatostatin. EFS significantly increased not only the number of immunoreactive somatostatin cells in the islet but also the concentration of immunoreactive somatostatin in portal effluent. It is concluded from the above results that intrapancreatic cholinergic activation elevates pancreatic exocrine secretion as well as release of endogenous somatostatin. Endogenous somatostatin exerts an inhibitory influence on exocrine secretion induced by intrapancreatic cholinergic activation via the islet-acinar portal system in the isolated pancreas of the rat.

Keyword

Somatostatin; Intrapancreatic cholinergic neurons; Pancreatic secretion; Rats

MeSH Terms

Amylases
Animals
Atropine
Cysteamine
Infusions, Intra-Arterial
Neurons
Pancreas
Pertussis Toxin
Portal System
Rats
Somatostatin*
Somatostatin-Secreting Cells
Amylases
Atropine
Cysteamine
Pertussis Toxin
Somatostatin