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Published on: March 8, 2018
Hyperosmolality and pancreatic blood flow
Pflugers Archiv : European Journal of Physiology
|August 29, 1977
Summary
Hyperosmolar solutions in cat pancreas caused vasodilation but not secretion. Pancreatic blood flow is regulated by factors other than tissue hyperosmolarity, despite its role in vasodilation.
Area of Science:
- Veterinary Medicine
- Gastroenterology
- Physiology
Background:
- The regulation of pancreatic blood flow and secretion is complex, involving various physiological and pharmacological stimuli.
- Understanding the interplay between osmolality, vasodilatation, and secretion is crucial for comprehending pancreatic function.
Purpose of the Study:
- To investigate the effects of hyperosmolar solutions on pancreatic vasodilatation and secretion in cats.
- To differentiate the stimuli causing pancreatic vasodilatation from those causing secretion and functional hyperemia.
Main Methods:
- Close intra-arterial infusions of hypertonic xylose, glucose, and sucrose solutions into the cat pancreas.
- Stimulation of the vagus nerve and infusion of secretin and cholecystokinin (CCK).
- Administration of bradykinin, papaverine, and isoprenaline to assess their effects on pancreatic blood flow and secretion.
Main Results:
- Hypertonic solutions induced marked pancreatic vasodilatation, correlating with induced glandular hyperosmolality.
- Vagal stimulation and secretin/CCK infusion evoked secretion and increased blood flow but did not alter venous osmolality.
- Bradykinin, papaverine, and isoprenaline increased pancreatic blood flow significantly without inducing secretion or changing venous osmolality.
Conclusions:
- Blood-borne hyperosmolality is a potent stimulus for pancreatic vasodilatation.
- Functional hyperemia in the pancreas is mediated by factors independent of regional tissue hyperosmolality.
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