1 Regulation of alpha and beta adrenergic receptors in man

Abstract

1.1. Adrenaline (A) supplementation of the incubation medium of monolayer cultures of hepatocytes at 0.1, 0.2, 0.3, 1 and 10 ng/ml resulted in consistently enhanced levels of secreted and newly synthesised non-secreted proteins; supplementation with 100 and 1000 ng/ml resulted in lower or unchanged levels. These effects were most consistent 6 hr after a medium change.2.2. Noradrenaline supplementation of the medium resulted in increased levels of secreted and non-secreted proteins at low concentrations (<2.4 ng/ml) at 6 hr after a medium change, but significantly decreased levels of both populations at high concentrations of noradrenaline (NA) (2.4 < NA < 1000 ng/ml), at 6–9 hr after a medium change and sustained to 24 hr, the most significant decrease being at 10 ng/ml.3.3. All combinations of concentrations of A + NA resulted in non-dose-dependent decreased levels of both the secreted and non-secreted soluble protein fractions. The most significant decreases occurred at concentrations of (1 + 5) and (10 + 10) ng/ml adrenaline + noradrenaline.4.4. Medium supplementation with adrenaline, noradrenaline or a combination of the two had no effect on the uptake of [3H]leucine by the cells.5.5. The results are discussed in relation to receptor status on the hepatocyte membranes.