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A Laboratory Method to Measure Contagious Yawning in Rats
Published on: June 14, 2019
Central interaction between physostigmine and histamine during yawning in rats
Esmaeal Tamaddonfard1, Hamid Soraya, Nasrin Hamzeh-Gooshchi
1Section of Physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, P.O. Box 1177, Urmia University, Urmia, Iran. e_tamaddonfard@yahoo.com
Pharmacological Reports : PR
|February 13, 2009
Summary
Physostigmine and histamine trigger yawning in rats, mediated by muscarinic and histamine receptors, respectively. These pathways interact, influencing yawning behavior.
Area of Science:
- Neuroscience
- Pharmacology
- Behavioral Science
Background:
- Yawning is a complex behavior with poorly understood neurochemical underpinnings.
- Acetylcholine and histamine are neurotransmitters implicated in various physiological processes, including arousal and motor control.
Purpose of the Study:
- To investigate the roles of muscarinic and histaminergic systems in regulating yawning behavior in rats.
- To explore the interactions between cholinergic and histaminergic pathways in the induction and modulation of yawning.
Main Methods:
- Rats were administered intraperitoneal physostigmine, subcutaneous atropine, and intracerebroventricular histamine, chlorpheniramine (H1 antagonist), and ranitidine (H2 antagonist).
- Separate and combined treatments were used to assess effects on yawning frequency.
- Dose-response relationships and antagonist effects were analyzed.
Main Results:
- Physostigmine significantly increased yawning, an effect blocked by atropine, indicating muscarinic receptor involvement.
- Histamine induced yawning, which was prevented by H1 and H2 receptor antagonists (chlorpheniramine and ranitidine).
- Histamine modulated physostigmine-induced yawning, while atropine influenced the interaction between histamine and chlorpheniramine.
Conclusions:
- Muscarinic receptors mediate physostigmine-induced yawning.
- Central H1 and, to a lesser extent, H2 histamine receptors are involved in histamine-induced yawning.
- Interactions between cholinergic and histaminergic systems play a role in regulating yawning behavior.
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