Autonomic function and control of pancreatic somatostatin

Area of Science:

• Endocrinology
• Neuroscience
• Gastroenterology

Background:

• D cells in the canine pancreas secrete somatostatin, a key hormone regulating gastrointestinal function.
• Autonomic nervous system regulation of pancreatic hormone secretion is crucial for maintaining homeostasis.
• Previous research has not fully elucidated the specific autonomic receptor subtypes on canine pancreatic D cells.

Purpose of the Study:

• To investigate the presence and function of alpha and beta adrenergic receptors on canine pancreatic D cells.
• To determine the effect of muscarinic and dopaminergic receptor stimulation on somatostatin release from D cells.
• To understand the potential physiological role of autonomic receptor stimulation in vivo.

Main Methods:

• Utilized canine pancreatic tissue preparations.
• Performed pharmacological stimulations to assess receptor activity.
• Measured somatostatin release in response to various autonomic receptor agonists and antagonists.

Main Results:

• Alpha-adrenergic receptor stimulation was found to inhibit somatostatin release.
• Beta-adrenergic receptor stimulation was found to increase somatostatin release.
• Muscarinic receptor stimulation resulted in mild inhibition of somatostatin secretion, and no dopaminergic receptors were detected on D cells.

Conclusions:

• Canine pancreatic D cells possess functional alpha and beta adrenergic receptors that modulate somatostatin secretion.
• Autonomic control of D cells involves adrenergic and muscarinic pathways, but not dopaminergic.
• These findings suggest that local ganglionic or central autonomic pathways may physiologically regulate D cells in vivo.