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Updated: Oct 20, 2026

In vitro Measurements of Tracheal Constriction Using Mice
Published on: June 25, 2012
Excitatory P1-purinoceptors on pre- and post-ganglionic cholinergic nerve terminals in the chick oesophagus
1Division of Pharmacology & Toxicology, Indian Veterinary Research Institute, Izatnagar.
Abstract:
The mechanism of action of ATP and the purinoceptors involved have been investigated on the chick oesophagus. The susceptibility of the excitatory responses to ATP/adenosine to tetrodotoxin indicates that their action is neurally mediated. Blockade of ATP/adenosine responses by atropine suggests the involvement of endogenous acetylcholine. ATP action depends on breakdown to AMP/adenosine, since theophylline blocks ATP/adenosine responses. The inhibition of ATP responses by pentolinium implies the involvement of preganglionic fibres.
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