Inactivation of Gi proteins by pertussis toxin diminishes the effectiveness of adrenergic stimuli in conduit arteries from spontaneously hypertensive rats

Title:

Inactivation of Gi proteins by pertussis toxin diminishes the effectiveness of adrenergic stimuli in conduit arteries from spontaneously hypertensive rats

Creator:

Zemančíková, A., Török, J., Josef Zicha, and Jaroslav Kuneš

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:3a6f7104-8dac-412a-a125-ec177ddd5017
uuid:3a6f7104-8dac-412a-a125-ec177ddd5017
issn:0862-8408

Subject:

Fyziologie člověka a srovnávací fyziologie, fyziologie, hypertenze, tepny, physiology, hypertension, arteries, pertussis toxin, adrenergic contractions, conduit arteries, angiotensin II, Gi proteins, 14, and 612

Type:

article, články, model:article, and TEXT

Format:

print, bez média, and svazek

Description:

Treatment with pertussis toxin (PTX) which eliminates the activity of Gi proteins effectively reduces blood pressure (BP) and vascular resistance in spontaneously hypertensive rats (SHR). In this study we have compared the functional characteristics of isolated arteries from SHR with and without PTX-treatment (10 μg/kg i.v., 48 h before the experiment). Rings of thoracic aorta, superior mesenteric artery and main pulmonary artery were studied under isometric conditions to measure the reactivity of these vessels to receptor agonists and to transmural electrical stimuli. We have found that the treatment of SHR with PTX had no effect on endothelium-dependent relaxation of thoracic aorta induced by acetylcholine. In PTX-treated SHR, the maximum contraction of mesenteric artery to exogenous noradrenaline was reduced and the dose-response curve to cumulative concentration of noradrenaline was shifted to the right. Similarly, a reduction in the magnitude of neurogenic contractions elicited by electrical stimulation of perivascular nerves was observed in the mesenteric artery from PTX-treated SHR. PTX treatment of SHR also abolished the potentiating effect of angiotensin II on neurogenic contractions of the main pulmonary artery. These results indicate that PTX treatment markedly diminishes the effectiveness of adrenergic stimuli in vasculature of SHR. This could importantly affect BP regulation in genetic hypertension., A. Zemančíková, J. Török, J. Zicha, J. Kuneš., and Obsahuje bibliografii a bibliografické odkazy

Language:

English

Rights:

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

Source:

Physiological research | 2008 Volume:57 | Number:2

Harvested from:

CDK

Metadata only:

false