Endothehal function 1s known to be ImpaIred m essential hypertensive patients In this study, we examined whether antihypertensive drugs improve forearm vasochlatory response to reactive hyperenna m 26 patients with essential hypertension (6222 years) without dtabetes melhtus, hyperhpldemla, coronary heart disease, or cerebrovascular disease AntIhypertensive drugs were never given or were chscontmued for at least 4 weeks before the study Patients were treated with monotherapy of &her temocaprtl (2 or 4 mg, n= 15) or amlochpme (2 5 or 5 mg, n= 11) for 6 months Forearm blood flow was measured by strain-gauge plethysmography Vasodilator response to the release of upper arm compression at 300 mm Hg for 5 minutes and to sublingual admmistration of mtroglycenn (0 3 mg) were assessed Changes of forearm blood flow response to reactive hyperenna were sigmficantly less m hypertensive patients (99218%) than m age- E ndothehal cells play a pIvota role m the modulation of vascular tone by releasing vasoactive substances, such as endothelm, prostaglandm, and endothelium-derived relaxing factor (EDRF). 1~2 In the early stage of atherogenesis, endothehal cell function 1s known to be disturbed.3 This results in lmpairment of the vasochlator response to acetylcholme, which requires Intact endothehal function 4 There 1s considerable evidence that the endothehum-dependent vasodilation 1s impaired in human essential hypertenslon.5.10 The effects of various antlhypertenslve drugs on hypertension-induced endothehal dysfunction have been examined widely. In animal studies, angiotensmconverting enzyme (ACE) mhWors have been shown to improve endothehal function. II-14 However, m human hypertension, the results are not consistent, several investigators demonstrated that ACE mhibltors improved endothelial dysfunction m hypertensive patients,l5-17 while others failed to show an lmprovement 18,19 The effect of calcium antagonists has not been fully examined except m rats13 and an acute human study '6 CelermaJer et al*0 evaluated endothehal function by Doppler system m the brachlal and femoral arteries during reactive hyperemla and after sublmgual adnumstration of nitroglycerm. Both procedures induce vasochlation; however, the former 1s partly mediated by Hlgashlosaka 577 Japan E-mail nagano@ gerlat med Osaka-u ac JP 0 1997 American Heart Assoclatlon, Inc EDRF,2',22 while the latter acts directly on smooth muscle cells. In this study, we used CelermaJor's method with modlficatlon to evaluate the effects of an ACE mhlbitor, temocapnl, and a calcium antagonist, amlochpine, on forearm vasodllator response m patients with essential hypertension These drugs were given as monotherapy for 6 months in hypertensive patients without any overt chnlcal evidence of atherosclerosis
Subjects
MethodsThe SubJects were 26 panents with essential hypertension aged 52 to 80 years (mean+-SEM, 62?2 years) and another 37 age-and sexmatched normotensive mdividuals as control Hypertension was defined as systolic blood pressure at the outpatient department of ...
