Variations in renal arteriolar diameter in deoxycorticosterone acetate-salt hypertensive rats. A microvascular cast study.

The relation between hypertensive glomerular damage and arteriolar diameter was examined in a microvascular cast study in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. The blood pressure and urinary protein excretion increased progressively in the DOCA rats. In controls afferent arteriolar diameters increased during the course of the experiment, and efferent arteriolar diameters remained unchanged. In the DOCA rats, however, afferent arteriolar diameters did not change significantly, while efferent arteriolar diameters increased. Histological studies showed severe arteriolosclerosis and glomerulosclerosis in the DOCA rats. The results show that these arteriolar changes might contribute to the reduction of glomerular capillary pressure in the development of DOCA-salt hypertension. However, they are not sufficient to protect glomeruli from hypertensive damage.