AJP - Cell Physiology, Vol 263, Issue 3 C623-C627, Copyright © 1992 by American Physiological Society
Beta 2-adrenoceptor density in fibroblast culture correlates with human NaCl sensitivity
P. Kotanko, O. Hoglinger and F. Skrabal
Department of Internal Medicine, Krankenhaus Barmherzige Bruder, Graz, Austria.
To study salt sensitivity in humans and its relation to expression of
adrenoceptors, 20 male normotensive Caucasians were investigated on a diet
of 180 mmol NaCl/day followed by 60 mmol NaCl/day over 2 wk and again by
180 mmol NaCl/day over 2 wk, and blood pressure changes were assessed by
long-term oscillatory blood pressure monitoring under basal conditions.
Individual cell cultures of skin fibroblasts from skin biopsies were also
established, and alpha 2- and beta 2-adrenoceptors were measured. Seven
subjects were salt sensitive, and the remainder were salt resistant.
Cultured skin fibroblasts in salt-sensitive subjects express less than half
the number of beta 2-adrenoceptors compared with salt-resistant subjects
(65 +/- 12.7 vs. 173 +/- 14.8 fmol/mg, P less than 0.001), and there is a
correlation between the absolute rise of blood pressure on a high-salt diet
and the density of beta 2-adrenoceptors (r = -0.67, P less than 0.01). It
remains to be established whether a reduced in vitro density of beta
2-adrenoceptors in cultured cells is causally related to salt sensitivity
in normotensive humans.
