Gene expression of vascular natriuretic peptide receptor in the aorta of hypertensive rats.

1. To elucidate the pathophysiologic role of vascular natriuretic peptide (NP) receptor in hypertension, we determined NP-A and NP-B receptor mRNA levels by means of ribonuclease protection assay in aorta of three types of hypertensive rats. 2. The NP-A receptor mRNA level was higher in stroke-prone spontaneously hypertensive rats (SHR-SP/Izm) and deoxycorticosterone acetate-salt hypertensive rats than that in their respective control rats. On the contrary, the NP-A receptor mRNA level was lower in NG-nitro-L-arginine-methyl ester (L-NAME)-induced hypertensive rats compared with that in the control. 3. The NP-B receptor mRNA level did not show any significant change in all three hypertensive rats compared with their respective controls. 4. The present study suggests that high blood pressure is not the major factor regulating the NP receptor gene expression and also that the receptor subtype is independently regulated from each other.