title: Vasoactive effects of prostaglandins from the perivascular fat of mesenteric resistance arteries in WKY and SHROB rats.
abstract: OBJECTIVE
  We have studied the vasoactive role of prostaglandins derived from perivascular adipose tissue (PVAT) and their effects on endothelial function in healthy rats and rats with metabolic syndrome (SHROB).
  
  
  METHODS
  Mesenteric resistance arteries (MRA) from SHROB and control rats (WKY) were mounted on wire myographs: a) together with a sphere of naturally occurring perivascular adipose tissue (with-PVAT group), or b) dissecting all the adventitial tissue (without-PVAT group).
  
  
  RESULTS
  Endothelial function, tested by acetylcholine reactivity of SHROB arteries with PVAT, was significantly lower than that of WKY. With-PVAT arteries, especially the SHROB, showed lower responses than those without PVAT. NO synthase inhibition diminished the acetylcholine responses in every group except the with-PVAT SHROB group. Blockade of cyclooxygenase-2, PGI2-IP, TXA2-TP, or TXA2 synthase increased to different extents the arterial responses in the SHROB with-PVAT group. PVAT from both rat strains revealed cyclooxygenase-2 activity and immunoassay confirmed the release of PGE2, PGI2 and TXA2.
  
  
  CONCLUSIONS
  Our major finding is that PVAT is a source of vasoactive prostaglandins in WKY and SHROB. We also report that the presence of visceral PVAT causes endothelial dysfunction of resistance arteries in the SHROB. The vascular responses to prostaglandins partly underlie the endothelial dysfunction of SHROB arteries.
authors.affiliation: Area of Physiology, Department of Medical Sciences, University of Castilla-La Mancha, School of Medicine and Regional Centre for Biomedical Research (CRIB), Albacete, Spain.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Mendizábal
authors.forename: Silvia
authors.initials: S
authors.lastname: Llorens
authors.forename: Eduardo
authors.initials: E
authors.lastname: Nava
mesh_terms: D000109:Acetylcholine / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology; D015232:Dinoprostone / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D011464:Epoprostenol / Q000378:metabolism; D066298:In Vitro Techniques; D050152:Intra-Abdominal Fat / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000378:metabolism* / Q000503:physiopathology; D024821:Metabolic Syndrome / Q000503:physiopathology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D011453:Prostaglandins / Q000378:metabolism* / Q000494:pharmacology; D051381:Rats; D011921:Rats, Inbred WKY; D011922:Rats, Mutant Strains; D013928:Thromboxane A2 / Q000378:metabolism; D013930:Thromboxane-A Synthase / Q000378:metabolism; D014655:Vascular Resistance; D014661:Vasoconstriction / Q000502:physiology; D014664:Vasodilation / Q000502:physiology
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D011453:Prostaglandins; D009569:Nitric Oxide; D013928:Thromboxane A2; D011464:Epoprostenol; D013930:Thromboxane-A Synthase; D015232:Dinoprostone; D000109:Acetylcholine; D019331:NG-Nitroarginine Methyl Ester
keywords: Cyclooxygenase-2; Endothelial function; Mesenteric resistance artery; Metabolic syndrome; Obesity; Perivascular adipose tissue; Prostaglandins; SHROB; Vasoactive adipokines