title: Exogenous hydrogen sulfide causes different hemodynamic effects in normotensive and hypertensive rats via neurogenic mechanisms.
abstract: 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.
authors.affiliation: Department of Experimental and Clinical Physiology, Medical University of Warsaw, Warszawa, Poland.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Sikora
authors.affiliation: Department of Experimental and Clinical Physiology, Medical University of Warsaw, Warszawa, Poland.
authors.forename: Adrian
authors.initials: A
authors.lastname: Drapala
authors.affiliation: Department of Experimental and Clinical Physiology, Medical University of Warsaw, Warszawa, Poland. Electronic address: mufnal@wum.edu.pl.
authors.forename: Marcin
authors.initials: M
authors.lastname: Ufnal
mesh_terms: D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001921:Brain / Q000378:metabolism; D006339:Heart Rate / Q000187:drug effects*; D006862:Hydrogen Sulfide / Q000378:metabolism*; D006973:Hypertension / Q000503:physiopathology*; D057967:Infusions, Intraventricular; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013440:Sulfides / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D013440:Sulfides; D000804:Angiotensin II; C025451:sodium bisulfide; D006862:Hydrogen Sulfide
keywords: Angiotensin II; Blood pressure; Brain; Hydrogen sulphide; Hypertension