Nitric oxide inhibition simulates the enhancement of alpha(1) agonist-induced vasoconstriction in diabetes

被引:19
作者
Dresner, LS
Wang, SP
West, MW
Ponomarenko, IN
Mueller, CM
Wait, RB
机构
[1] Department of Surgery, State University of New York, Health Science Center at Brooklyn, Brooklyn
[2] Dept. of Surgery, State University of New York, Health Science Center at Brooklyn, Brooklyn, NY 11203
关键词
D O I
10.1006/jsre.1997.5106
中图分类号
R61 [外科手术学];
学科分类号
摘要
We have previously reported that endothelium-dependent, nitric oxide (NO)-mediated vasorelaxation is impaired in diabetic mesenteric arteries. We hypothesized that vasoconstrictor responses should therefore be enhanced. The purpose of this study was to determine whether diabetic mesenteric arteries exhibit in creased vasoconstrictor responses, and to investigate if these changes are receptor and/or NO mediated. Thirty age-matched male Sprague-Dawley rats were divided into control (C) and diabetic (D, streptozotocin: 60 mg/kg) groups and studied after 4 weeks, Terminal branches of ileal mesenteric arteries (300 +/- 9 mu m) were isolated, pressurized, and superfused with modified Krebs solution. Changes in vessel internal diameter were measured and dose-response curves (DRC) for each vasoactive agent were determined. Each vessel was initially constricted with 40 mM of KCl to determine maximal vasoconstriction. Phenylephrine (Phe, 10(-8)-10(-4) M) and UK14304 (10(-9)-10(-5) M) were used to determine alpha(1)- and alpha(2)-receptor responses, respectively. Similar studies were performed in the presence of N-omega-nitro-L-arginine methyl ester (L-NAME, 10(-4) M), a competitive inhibitor of NO synthase. Maximal response (Max), area under the curve (AUG), and vessel sensitivity (ED50) for each DRC were calculated. Comparisons among groups were made using analysis of variance and Student's t test with Bonferroni correction. There were no differences in vasoconstrictor responses induced by KCI (C: 82 +/- 2% vs D: 80 +/- 1%). alpha(1)-vasoconstrictor responses to Phe were enhanced in diabetes with significantly higher Max (96 +/- 2% vs 83 +/- 3%), and AUC (1.92 +/- 0.09 vs 1.56 +/- 0.08), but no difference in ED50. The addition of L-NAME enhanced only Phe-induced vasoconstrictor response significantly in control rats, Thus, differences in Phe-induced vasoconstrictor responses between C and D were abolished in the presence of L-NAME. alpha(2)-vasodilator responses induced by UK14304 were similar between C and D and unaffected by L-NAME. alpha(1)-, but not alpha(2)- vasoconstrictor responses are enhanced in streptozotocin-induced diabetic rats. These enhanced responses can be duplicated by treatment of control vessels with L-NAME. (C) 1997 Academic Press.
引用
收藏
页码:119 / 123
页数:5
相关论文
共 26 条
[11]   STRUCTURAL AND FUNCTIONAL ORIGINS OF SUPPRESSED ACETYLCHOLINE VASODILATION IN DIABETIC RAT INTESTINAL ARTERIOLES [J].
LASH, JM ;
BOHLEN, HG .
CIRCULATION RESEARCH, 1991, 69 (05) :1259-1268
[12]  
MARTIN W, 1986, J PHARMACOL EXP THER, V237, P529
[13]   MECHANISM OF IMPAIRED RESPONSES OF CEREBRAL ARTERIOLES DURING DIABETES-MELLITUS [J].
MAYHAN, WG ;
SIMMONS, LK ;
SHARPE, GM .
AMERICAN JOURNAL OF PHYSIOLOGY, 1991, 260 (02) :H319-H326
[14]   NEW INSIGHTS INTO THE REGULATION OF INDUCIBLE NITRIC-OXIDE SYNTHESIS [J].
MORRIS, SM ;
BILLIAR, TR .
AMERICAN JOURNAL OF PHYSIOLOGY, 1994, 266 (06) :E829-E839
[15]   INSULIN REVERSAL OF DIABETES-INDUCED INHIBITION OF VASCULAR CONTRACTILITY IN THE RAT [J].
PFAFFMAN, MA ;
BALL, CR ;
DARBY, A ;
HILMAN, R .
AMERICAN JOURNAL OF PHYSIOLOGY, 1982, 242 (04) :H490-H495
[16]  
PIEPER GM, 1989, AM J PHYSIOL, V257, pH1327
[17]   ENDOTHELIUM-MEDIATED VASCULAR FUNCTION IN INSULIN-DEPENDENT DIABETES-MELLITUS [J].
POSTON, L ;
TAYLOR, PD .
CLINICAL SCIENCE, 1995, 88 (03) :245-255
[18]  
RONGEN GA, 1994, NETH J MED, V44, P26
[19]  
RUFFOLO RR, 1984, J CARDIOVASC PHARM, V6, P1011
[20]  
SCARBOROUGH NL, 1984, J PHARMACOL EXP THER, V231, P597