Rat intestinal cell atrial natriuretic peptide receptor coupled to guanylate cyclase.
The present studies were initiated to determine if cells of intestinal origin possess the molecular components supporting a response to atrial natriuretic peptides. Specific binding in cultured rat ileal cells with 125I-labeled atrial natriuretic peptide was saturable and of high affinity. Scatchard analyses showed a single population of binding sites with a Kd of 2.1 nmol/L and a Bmax of 300 fmol/mg protein. Atrial natriuretic peptide activated particulate guanylate cyclase 5- to 10-fold in a concentration- and time-dependent fashion. The EC50 for activation of enzyme by atrial natriuretic peptide was 6 nmol/L. Accumulation of cyclic guanosine monophosphate stimulated by atrial natriuretic peptide was observed in the intracellular (25-fold) and extracellular (50-fold) compartments and was dependent on concentration and time. Half-maximum intracellular accumulation was observed with 10 nmol/L atrial natriuretic peptide. These data suggest a role for atrial natriuretic peptides in the gastrointestinal tract.
Crane
M R
MR
Department of Medicine, Stanford University School of Medicine, California.
O'Hanley
P
P
Waldman
S A
SA
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000493:pharmacokinetics*; D001665:Binding Sites; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000378:metabolism; D004789:Enzyme Activation; D006162:Guanylate Cyclase / Q000378:metabolism*; D007082:Ileum / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D017461:Receptors, Atrial Natriuretic Factor; D011956:Receptors, Cell Surface / Q000378:metabolism*
D011956:Receptors, Cell Surface; D009320:Atrial Natriuretic Factor; D006162:Guanylate Cyclase; D017461:Receptors, Atrial Natriuretic Factor; D006152:Cyclic GMP