Interactions of atrial natriuretic peptide with A7r5 cells.

The interactions of Atrial Natriuretic Peptide with its receptors were investigated with the vascular smooth muscle cells from the A7r5 cell line. Displacement experiments of [125I]rat-Atrial Natriuretic Peptide by rat-Atrial Natriuretic Peptide revealed a single class of receptors with a Kd = 0.21 +/- 0.08 nM and a Bmax = of 35 +/- 16 fmol/mg of protein. Furthermore, the complex [125I]r-Atrial Natriuretic Peptide was internalised by a heatsensitive process. Finally, Atrial Natriuretic Peptide increased cyclic Guanosyl 3',5' Mono Phosphate in a time dependent and dose dependent way, a concentration of 0.1 microM increasing cyclic Guanosyl 3',5' Mono Phosphate level by a factor of 8.3 times when compared to basal level.