Physical exercise-induced cardiovascular adjustments are modulated by muscarinic cholinoceptors within the ventromedial hypothalamic nucleus

Title:

Physical exercise-induced cardiovascular adjustments are modulated by muscarinic cholinoceptors within the ventromedial hypothalamic nucleus

Creator:

Wanner, S. P., Guimarães, J. B., Pires, W., La Guardia, R. B., Haibara, A. S., Marubayashi, U., Coimbra, C. C., and Lima, N. R. V.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:d84a7370-b616-4f88-af7c-1aa7e8bb8046
uuid:d84a7370-b616-4f88-af7c-1aa7e8bb8046

Subject:

Fyziologie člověka a srovnávací fyziologie, acetylcholin, únava, acetylcholine, fatigue, hypothalamus, methylatropine, 14, and 612

Type:

article, články, model:article, and TEXT

Format:

print

Description:

The effects of blocking ventromedial hypothalamic nucleus (VMH) muscarinic cholinoceptors on cardiovascular responses were investigated in running rats. Animals were anesthetized with pentobarbital sodium and fitted with bilateral cannulae into the VMH. After recovering from surgery, the rats were familiarized to running on a treadmill. The animals then had a polyethylene catheter implanted into the left carotid artery to measure blood pressure. Tail skin temperature (Ttail), heart rate, and systolic, diastolic and mean arterial pressure were measured after bilateral injections of 0.2 μl of 5 × 10−9 mol methylatropine or 0.15 M NaCl solution into the hypothalamus. Cholinergic blockade of the VMH reduced time to fatigue by 31% and modified the temporal profile of cardiovascular and Ttail adjustments without altering their maximal responses. Mean arterial pressure peak was achieved earlier in methylatropine-treated rats, which also showed a 2-min delay in induction of tail skin vasodilation, suggesting a higher sympathetic tonus to peripheral vessels. In conclusion, muscarinic cholinoceptors within the VMH are involved in a neuronal pathway that controls exercise-induced cardiovascular adjustments. Furthermore, blocking of cholinergic transmission increases sympathetic outflow during the initial minutes of exercise, and this higher sympathetic activity may be responsible for the decreased performance., S. P. Wanner ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Source:

Physiological research | 2010 Volume:59 | Number:2

Harvested from:

CDK

Metadata only:

false