Effects of Inducible Nitric Oxide Synthase Inhibition on Cardiovascular Risk of Adult Endotoxemic Female Rats: Role of Estrogen.

摘要: Aim: Autonomic modulation responds to ovarian hormones and estrogen increases nitric oxide bioavailability. Also, females have minor susceptibility sepsis a higher survival rate. However, few studies evaluated the role of in cardiovascular, autonomic, oxidative parameters during initial endotoxemia under inducible synthase (iNOS) inhibition female rats. Methods: Female wistar rats were subjected ovariectomy divided into three groups: OVX (ovariectomized), OVX+E (OVX plus daily estradiol) SHAM (false surgery). After 8 weeks, mean arterial pressure (MAP) heart rate (HR) recorded non-anesthetized catheterized rats, before after intravenous LPS injection, preceded by S-methylisothiourea sulfate (SMT) or sterile saline. Cardiovascular recordings underwent spectral analysis for evaluation autonomic modulation. Two hours LPS, plasma was collected assess total radical-trapping antioxidant (TRAP), nitrite levels (NO2), lipoperoxidation (LOOH), paraoxonase 1 (PON1) activity. Results: treated with SMT presented decrease MAP, when compared saline-LPS groups. At this same time, all SMT+LPS groups an increase sympathetic parasympathetic HR. saline+LPS, decreased (TRAP) SHAM. When SMT+LPS, did not altered TRAP, while estradiol reduced LOOH levels. Conclusion: iNOS would be responsible consumption reserves endotoxemia, since is inhibited, treatment could protective inflammatory challenges.