Indirect evidence for vascular uptake of circulating renin in hypertensive patients.
To evaluate whether, in the forearm of hypertensive patients with different circulating renin profiles, local beta-adrenergic receptor-induced production of active renin, plasma renin activity, angiotensin I (Ang I), and angiotensin II (Ang II) was or was not related to the renin profile, we studied four groups of patients: 1) hypertensive patients with primary aldosteronism and suppressed circulating plasma renin activity values (0.15 +/- 0.1 ng Ang I/mL per hour; n = 7), 2) essential hypertensive patients with low (0.47 +/- 0.1 ng Ang I/mL per hour; n = 8) circulating plasma renin activity values, 3) essential hypertensive patients with normal (2.48 +/- 0.52 ng Ang I/mL per hour; n = 8) circulating plasma renin activity value, and 4) renovascular hypertensive patients with high circulating plasma renin activity values (4.16 +/- 2.1 ng Ang I/mL per hour; n = 10). Isoproterenol was infused into the brachial artery, and active renin, plasma renin activity, and Ang I and Ang II forearm balance (venous-arterial differences corrected for forearm blood flow by strain-gauge plethysmography) were measured. Despite a comparable vasodilation, beta-adrenergic stimulation failed to release active renin, plasma renin activity, and Ang I and Ang II in primary aldosteronism. It slightly increased them (except for Ang I) in low renin patients but determined a local production in normal renin and renovascular hypertensive patients. The individual increments in plasma renin activity and Ang II release induced by isoproterenol showed a correlation with the renin profile.(ABSTRACT TRUNCATED AT 250 WORDS)
I Clinica Medica, University of Pisa, Italy.
S
S
Taddei
A
A
Virdis
B
B
Abdel-Haq
R
R
Giovannetti
P
P
Duranti
A M
AM
Arena
S
S
Favilla
A
A
Salvetti
D000328:Adult; D000803:Angiotensin I / Q000378:metabolism; D000804:Angiotensin II / Q000378:metabolism; D001808:Blood Vessels / Q000378:metabolism*; D005260:Female; D005542:Forearm / Q000098:blood supply; D006801:Humans; D006929:Hyperaldosteronism / Q000150:complications; D006973:Hypertension / Q000150:complications / Q000378:metabolism*; D006978:Hypertension, Renovascular / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011943:Receptors, Adrenergic, beta / Q000502:physiology; D012039:Regional Blood Flow; D012083:Renin / Q000097:blood* / Q000378:metabolism; D012084:Renin-Angiotensin System / Q000502:physiology
D011943:Receptors, Adrenergic, beta; D000804:Angiotensin II; D000803:Angiotensin I; D012083:Renin