title: Changes in the profile of NO synthases affect coronary blood flow autoregulation and myocardial contractile activity during restraint stress in rats.
abstract: The efficiency of autoregulation of the coronary blood flow and contractile activity of the myocardium in the presence of inhibitors of constitutive and inducible NO synthases was studied in rats exposed to 6-h restraint stress. Intracoronary administration of S-methylisothiourea (10 μmol/liter), but not L-NAME (60 μmol/liter) fully prevented post-stress increase in the volume coronary blood flow rate, intensity of heart perfusion, and reduction of ventricular developed pressure at all levels of perfusion pressure. Real-time PCR showed 6-fold increased expression of inducible NO-synthase mRNA in the heart tissue against the background of unchanged expression of neuronal and endothelial NO synthases and 2-3-fold elevated content of transcripts of stress-inducible genes Hspa1a and Hspbp1. It was shown that the hypotension of coronary vessels and reduced contractile function of the myocardium are related to NO production by inducible NO synthase in endotheliocytes of coronary vessels and cardiomyocytes.
authors.affiliation: P. M. Masherov Vitebsk State University, Vitebsk, Belarus, solodkov60@mail.ru.
authors.forename: A P
authors.initials: AP
authors.lastname: Solodkov
authors.forename: S S
authors.initials: SS
authors.lastname: Lazuko
authors.forename: E N
authors.initials: EN
authors.lastname: Knyazev
authors.forename: I N
authors.initials: IN
authors.lastname: Nechaev
authors.forename: N A
authors.initials: NA
authors.lastname: Krainova
mesh_terms: D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D006706:Homeostasis / Q000502:physiology*; D007550:Isothiuronium / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D012149:Restraint, Physical / Q000009:adverse effects*; D013053:Spectrophotometry; D018709:Statistics, Nonparametric; D013312:Stress, Physiological / Q000502:physiology*; D017725:Ventricular Pressure / Q000187:drug effects / Q000502:physiology
chemical_list: D017931:DNA Primers; D007550:Isothiuronium; D019001:Nitric Oxide Synthase; C027744:S-methylisothiopseudouronium; D019331:NG-Nitroarginine Methyl Ester