Effect of diabetes mellitus on flow-mediated and endothelium-dependent dilatation of the rat basilar artery.

نویسندگان

  • K Fujii
  • D D Heistad
  • F M Faraci
چکیده

BACKGROUND AND PURPOSE Diabetes mellitus may impair endothelium-dependent responses in cerebral arterioles. The basilar artery dilates in response to increases in blood flow. The goal of this study was to examine effects of diabetes mellitus on "flow-mediated" and endothelium-dependent dilatation of the basilar artery. METHODS Diabetes was induced in rats with 50 mg/kg streptozotocin. Six months later, vessel diameter and velocity of blood flow through the basilar artery were measured using a cranial window in anesthetized rats under baseline conditions and during occlusion of the carotid arteries. Changes in vessel diameter were also measured during topical application of acetylcholine and sodium nitroprusside. RESULTS With aortic pressure maintained at baseline levels, blood flow velocity through the basilar artery increased similarly in control and diabetic rats during unilateral common carotid artery occlusion and during bilateral occlusion. In control and diabetic rats, diameter of the basilar artery increased by 10 +/- 2% and 10 +/- 4% during unilateral occlusion and by 27 +/- 5% and 31 +/- 4% during bilateral occlusion, respectively. Thus, diabetes did not impair flow-mediated dilatation of the basilar artery. In contrast, dilatation in response to 10(-5) M topical acetylcholine was less in diabetic rats (13 +/- 2%) than in control rats (45 +/- 8%) (p less than 0.05). Dilator responses to nitroprusside were not impaired by diabetes. CONCLUSIONS The findings suggest that diabetes produces impairment of endothelium-dependent responses to acetylcholine, but not flow-mediated dilatation, in the basilar artery.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Relaxatory Effect of Gamma-Aminobutyric Acid (GABA) is Mediated by Same Pathway in Diabetic and Normal Rat Mesenteric Bed vessel

Objective(s) Diabetes related dysfunction of resistance vessels is associated with vascular occlusive diseases. Vasorelaxant agents may have a role in control of diabetic cardiovascular complications. Gamma aminobutyric acid (GABA) has demonstrated to cause vasorelaxation. The present study was designed to determine i) the vasorelaxatory effect of GABA on diabetic vessels and ii) the role of e...

متن کامل

Influence of exercise on dilatation of the basilar artery during diabetes mellitus.

Our goal was to examine whether exercise training alleviates impaired nitric oxide synthase (NOS)-dependent dilatation of the basilar artery in Type 1 diabetic rats. To test this hypothesis, we measured in vivo diameter of the basilar artery in sedentary and exercised nondiabetic and diabetic rats in response to NOS-dependent (acetylcholine) and -independent (nitroglycerin) agonists. To determi...

متن کامل

The vasodilatory action of telmisartan on isolated mesenteric artery rings from rats

Objective(s): Angiotensin Ⅱ type 1 receptor blockers (ARBs) represent one of the widely used antihypertensive agents. In addition to anti-hypertension effect, some ARBs also show other molecular effects such as activating peroxisome proliferator-activated receptor-γ and so on. Here we studied the effects of telmisartan on the rat isolated mesenteric artery rings pre-contracted by phenylephrine ...

متن کامل

Role of tyrosine kinase in dilator responses of rat basilar artery in vivo.

We tested the hypothesis that dilator responses of the basilar artery to endothelium-dependent vasodilators are mediated by activation of tyrosine kinase in vivo. Using a cranial window in anesthetized rats, we examined responses of the basilar artery to acetylcholine and bradykinin. Topical application of acetylcholine and bradykinin increased diameter of the basilar artery in a concentration-...

متن کامل

Treatment with dimethylthiourea prevents impaired dilatation of the basilar artery during diabetes mellitus.

The goal of this study was to test the hypothesis that the synthesis/release of hydroxyl radical accounts for impaired nitric oxide synthase-dependent dilatation of the basilar artery during diabetes mellitus. We measured the diameter of the basilar artery in vivo in nondiabetic and diabetic rats (streptozotocin, 50-60 mg/kg ip) in response to nitric oxide synthase-dependent agonists (acetylcho...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Stroke

دوره 23 10  شماره 

صفحات  -

تاریخ انتشار 1992