Alpha-adrenoceptors and the kidney.
Sympathetic nerves may modify various aspects of renal function including renal haemodynamics, renin secretion and sodium output. In a series of experiments we found that within the human kidney alpha 2-adrenoceptors are of greater importance than alpha 1-receptors in mediating the adrenergic effects. For instance, intrarenal infusion of an alpha 1-antagonist has a small effect on renal perfusion, whereas blockade of alpha 2-receptors increases renal flow profoundly. There is evidence that the relevant receptors are located at a postjunctional site. Alpha 2-receptors also play an inhibitory role in renin secretion. Recent data suggest that the alpha 2-receptor, which reduces renin release, is located presynaptically. Thus, stimulation of this receptor reduces noradrenaline overflow, and hence diminishes beta-adrenoceptor mediated increases in renin.
de Leeuw
P W
PW
Department of Medicine, Zuiderziekenhuis, Rotterdam, The Netherlands.
Birkenhäger
W H
WH
D000317:Adrenergic alpha-Antagonists; D017292:Doxazosin; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D007668:Kidney / Q000294:innervation*; D011224:Prazosin / Q000031:analogs & derivatives; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000502:physiology*; D012079:Renal Circulation; D012083:Renin / Q000378:metabolism; D015016:Yohimbine
D000317:Adrenergic alpha-Antagonists; D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; D012083:Renin; D017292:Doxazosin; D011224:Prazosin