Related Experiment Videos
Local effect of vasoactive intestinal polypeptide on human sweat-gland function
Y Yamashita1, T Ogawa, N Ohnishi
1Department of Physiology, Aichi Medical University, Japan.
The Japanese Journal of Physiology
|January 1, 1987
Summary
Vasoactive intestinal polypeptide (VIP) enhances drug-induced sweating by cholinergic neurons, particularly in cooler conditions. This suggests VIP plays a role in regulating sweat gland function and oxygen supply.
Area of Science:
- Physiology
- Neuroendocrinology
- Dermatology
Background:
- Vasoactive intestinal polypeptide (VIP) is a potential co-transmitter in cholinergic neurons innervating sweat glands.
- Understanding VIP's role is crucial for comprehending sweat gland regulation.
Purpose of the Study:
- To investigate the physiological significance of VIP on drug-induced sweating.
- To determine VIP's local effect on sweat secretion and its interaction with methacholine chloride (MCH).
Main Methods:
- Intradermal injections of VIP, MCH, or VIP plus MCH were administered to forearm test areas.
- Sweat rate was continuously recorded using capacitance hygrometry.
- Experiments were conducted in both cool (23°C) and hot (35°C) environments, with and without nerve blocks.
Main Results:
- In a cool environment, VIP alone did not induce sweating but significantly increased MCH-induced sweating.
- The sweat-facilitatory effect of VIP was most pronounced at a concentration of 10⁻⁵ g/ml, correlating with the greatest rise in local skin temperature.
- In a hot environment with nerve block, VIP's sweat-facilitatory effect was less pronounced, suggesting reduced efficacy under passive vasodilation.
Conclusions:
- VIP acts as a sweat-facilitating agent, augmenting cholinergic stimulation of sweat glands.
- The effect of VIP on sweating is modulated by ambient temperature and cutaneous vascular tone.
- VIP may contribute to ensuring adequate oxygen supply to active sweat glands, especially when vasoconstrictor tone is high.