Enhanced protein synthesis of heart in adrenal-regeneration hypertension and its reduction following antihypertensive treatment.

After unilateral nephrectomy and bilateral adrenal enucleation at 5 weeks of age, salt-loaded rats developed hypertension (ARH) at 6 weeks. Fibrous vascular protein and in vivo incorporation of 3H-lysine into this protein fraction were measured at 15 weeks of age in these animals. This study demonstrates: (1) that incorporation rates of 3H-lysine into cardiac collagen and elastin in ARH rats were greater than in control rats (p less than 0.001, respectively), and (2) that administration of phenoxy-benzamine hydrochloride decreased the incorporation of tritiated lysine into cardiac collagen in ARH rats, concomitant with a reduction in blood pressure. Based on these findings, increased synthesis of cardiac collagen and elastin appears to play an important role in the development of hypertension in ARH.