title: Gallic acid improves endothelium-dependent vasodilatory response to histamine in the mesenteric vascular bed of diabetic rats.
abstract: BACKGROUND
  Endothelial dysfunction is one of the many complications caused by diabetes mellitus. The aim of the present study was to evaluate the effects of gallic acid (GA) on the mesenteric vascular bed (MVB) response to histamine in diabetic rats.
  
  
  METHODS
  Forty male Wistar rats were randomly assigned to a control group, an untreated alloxan-induced diabetic group and three diabetic groups treated with different doses of GA. Six weeks after induction of diabetes and GA treatment, total antioxidant capacity (TAC), malondialdehyde (MDA) concentrations, and the vasodilatory response to histamine of the MVB (measured as changes in perfusion pressure) were determined.
  
  
  RESULTS
  The vasodilatory response to histamine and TAC decreased, whereas MDA increased in the plasma from diabetic rats (P < 0.01). However, in the presence of 3 × 10-5mol/L NG-nitro-l-arginine methyl ester (a nitric oxide synthase inhibitor) and 1 × 10-5mol/L indomethacin (an inhibitor of prostaglandin production), the vasodilatory response of the MVB to histamine was reduced in all groups (P < 0.001). Treatment of diabetic rats with 20 and 40 mg/kg per day GA, but not 10 mg/kg per day GA, increased TAC and decreased MDA concentrations (P < 0.01 and P < 0.001 vs untreated diabetic rats, respectively) and significantly improved the vasodilatory response to histamine (P < 0.05 and P < 0.001, respectively).
  
  
  CONCLUSIONS
  The results show that, in diabetic rats, the endothelium-dependent vasodilatory response of the MVB to histamine is significantly decreased and depends on both nitric oxide- and prostaglandin-producing pathways and may be mediated by oxidative stress. Treatment with the antioxidant GA restored the vasodilatory response of the MVB to histamine.
authors.affiliation: Department of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.|Ahvaz Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.|Atherosclerosis Research Center at Golestan Hospital, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.
authors.forename: Mohammad
authors.identifier: http://orcid.org/0000-0003-2290-8565
authors.initials: M
authors.lastname: Badavi
authors.affiliation: Department of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Bazaz
authors.affiliation: Department of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.|Ahvaz Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.
authors.forename: Mahin
authors.initials: M
authors.lastname: Dianat
authors.affiliation: Department of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.|Ahvaz Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Sarkaki
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000187:drug effects* / Q000502:physiology; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism / Q000503:physiopathology*; D004730:Endothelium, Vascular / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005707:Gallic Acid / Q000494:pharmacology*; D006632:Histamine / Q000494:pharmacology*; D017442:Histamine Agonists / Q000494:pharmacology; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D008643:Mesentery / Q000098:blood supply; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D011897:Random Allocation; D017208:Rats, Wistar; D014664:Vasodilation / Q000187:drug effects* / Q000502:physiology
chemical_list: D016861:Cyclooxygenase Inhibitors; D004791:Enzyme Inhibitors; D017442:Histamine Agonists; D009569:Nitric Oxide; D005707:Gallic Acid; D006632:Histamine; D019331:NG-Nitroarginine Methyl Ester; D007213:Indomethacin
keywords: diabetes mellitus; endothelium; gallic acid; histamine; mesenteric arteries; 内皮; 没食子酸; 糖尿病; 组胺; 肠系膜动脉