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Updated: Aug 19, 2026

In vitro Measurements of Tracheal Constriction Using Mice
Published on: June 25, 2012
Thyrotropin-releasing hormone (TRH) evokes chloride secretion via cholinergic pathways in the guinea-pig ileum
1Department of Physiology, College of Medicine, Ohio State University, Columbus 43210.
Abstract:
The effect of thyrotropin-releasing hormone (TRH) on ion transport in the guinea-pig ileum was investigated in flux chambers. TRH evoked a concentration-dependent increase in short-circuit current that was due to active anion secretion. The response to TRH was prevented by tetrodotoxin and nearly abolished by atropine, but was not affected by mecamylamine. The results suggest that TRH plays a role as a neuromodulator or neurotransmitter that influences secretory processes by directly or indirectly activating cholinergic motor neurons.
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