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Updated: Aug 10, 2026

Gastrointestinal Motility Monitor (GIMM)
08:15

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Octreotide inhibits increases in short-circuit current induced in rat colon by VIP, substance P, serotonin and

J E Fassler1, T M O'Dorisio, H S Mekhjian

  • 1Department of Internal Medicine, Ohio State University, Columbus.

Regulatory Peptides
|July 30, 1990
PubMed

Insights

Octreotide (OCT), a somatostatin analog, inhibits intestinal secretion by affecting short-circuit current (Isc). OCT reduces responses to VIP, serotonin, and substance P, indicating multiple inhibitory mechanisms.

Area of Science:

  • Gastroenterology
  • Pharmacology
  • Physiology

Background:

  • Vasoactive intestinal peptide (VIP), aminophylline, serotonin (5-HT), and substance P are key regulators of intestinal secretion.
  • Octreotide (OCT), a somatostatin analog, is known to modulate various physiological processes.

Purpose of the Study:

  • To investigate the effect of OCT on short-circuit current (Isc) in rat colon.
  • To determine OCT's impact on intestinal secretory responses induced by specific secretagogues.

Main Methods:

  • Measurement of short-circuit current (Isc) in rat colon tissues.
  • Administration of OCT at varying concentrations.
  • Stimulation of tissues with VIP, aminophylline, 5-HT, and substance P.

Main Results:

  • OCT significantly decreased basal Isc, with maximum effect at 10(-6) M.
  • OCT inhibited intestinal secretory responses to VIP, 5-HT, and substance P.
  • OCT shifted the aminophylline concentration-response curve but did not reduce the maximum response.

Conclusions:

  • OCT inhibits intestinal secretion through multiple mechanisms.
  • OCT affects both cAMP-dependent and calcium-linked pathways involved in intestinal secretion.

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