Related Experiment Video

Updated: Aug 16, 2026

In vitro Measurements of Tracheal Constriction Using Mice
10:20

In vitro Measurements of Tracheal Constriction Using Mice

Published on: June 25, 2012

(R)-alpha-methylhistamine augments neural, cholinergic bronchospasm in guinea pigs by histamine H1 receptor

J A Hey1, M del Prado, R W Egan

  • 1Schering-Plough Research, Bloomfield, NJ 07003.

European Journal of Pharmacology
|February 18, 1992
PubMed

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Direct-acting cholinergic agonists exert their pharmacological actions by mimicking the effects of acetylcholine on postsynaptic muscarinic receptors to generate parasympathetic responses. These agents elicit a range of physiological responses, including cardiovascular effects. For example, activation of muscarinic receptors induces bradycardia, decreased cardiac output, reduced peripheral resistance, and consequent hypotension. In the eye, stimulation of M3 receptors leads to smooth muscle...
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