Background: Increasing evidence suggests that disturbances in H2S homeostasis may participate in the development of hypertension. In this study we compared hemodynamic responses to intracerebroventricular (ICV) infusions of sodium hydrosulfide (NaHS), a H2S donor, between normotensive rats (WKY), spontaneously hypertensive rats (SHR) and angiotensin II - induced hypertensive rats (WKY-Ang II).
Methods: We tested the effects of NaHS on mean arterial blood pressure (MABP) and heart rate (HR) in 12-14-week-old, male rats. MABP and HR were continuously recorded at baseline and during ICV infusion of either vehicle (Krebs-Henseleit buffer) or NaHS.
Results: ICV infusions of the vehicle did not affect MABP and HR. WKY rats infused with 30 nmol/h of NaHS showed a mild decrease in MABP and HR. ICV infusion of 100 nmol/h produced a biphasic response i.e. mild hypotension and bradycardia followed by an increase in MABP and HR, whereas, the infusion of 300 nmol/h of the H2S donor caused a monophasic increases in MABP and HR. In contrast, SHR rats as well as WKY-Ang II rats showed a decrease in MABP and HR during ICV infusions of NaHS.
Conclusions: The results provide further evidence for the involvement of H2S in the neurogenic regulation of the circulatory system and suggest that alterations in H2S signaling in the brain could be associated with hypertension.
Keywords: Angiotensin II; Blood pressure; Brain; Hydrogen sulphide; Hypertension.
Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.