AJP - Heart and Circulatory Physiology, Vol 253, Issue 2 358-H364, Copyright © 1987 by American Physiological Society
Dopaminergic stimulation of cAMP accumulation in cultured rat mesangial cells
P. J. Shultz, J. R. Sedor and H. E. Abboud
Dopamine (DA) alters renal hemodynamics, and DA receptors have been
demonstrated in isolated glomeruli. To determine the glomerular cell type
bearing DA receptors, we studied the effect of dopaminergic agonists and
antagonists on adenosine 3',5'-cyclic monophosphate (cAMP) accumulation in
rat glomerular mesangial and epithelial cells in culture. DA caused a
marked dose- and time-dependent increase in cAMP accumulation in mesangial
but not epithelial cells. The stimulatory effect of DA was abolished by the
DA antagonists haloperidol, trifluoperazine, and cis-thiothixene but not by
beta- or alpha-adrenergic or histamine antagonists. Similar to the effects
of DA, two dopamine type I receptor agonists, fenoldopam and SKF 38393,
markedly stimulated cAMP accumulation in the mesangial cells. Moreover, the
effects of DA were blocked by Sch 23390, a specific DA1 receptor
antagonist, but not domperidone, a specific DA2 antagonist. These results
show that DA regulates cAMP accumulation in mesangial cells via DA1-type
receptors.
