Recently it is known renal medullar will be play a important role of blood pressure control and pressure natriuresis. Renomedullary antihypertensive mechanism is activated by increasing perfusion pressure of kidney and can be inhibited by sympathetic ...
Recently it is known renal medullar will be play a important role of blood pressure control and pressure natriuresis. Renomedullary antihypertensive mechanism is activated by increasing perfusion pressure of kidney and can be inhibited by sympathetic nerve stimulation or blockade of nitric oxide(NO) formation. It is important to know what is affect on renal regional blood flow, especially renal medullary blood flow(MBF). For the purpose of investigating the effect of the renal sympathetic nerve on regional blood flow during infusion of blocking NO synthesis(by N^(ω)-nitro-L-arginine methylester:L-NAME) in spontaneous hypertensive rat(SHR) and Wistar rats normal control, Mean arterial pressure(MAP), total renal blood flow(TRBF), midcortical blood flow(CBF), inner medullary blood flow were measured in innervated or denervated renal sympathetic nerve group of SHR and Wister rats.
All group that received the L-NAME were seen increasing MAP while TRBF, CBF and MBF decreased and the decrease of TRBF in SHR is more marked than in Wistar rat. In spite of increasing the MAP, MBF in all four group decreased, respectively C: 220 ± 3 U, 205 ± 2 U Wi : 215 ± 4 U, 165 ± 12 U Wd :218 ± 3 U, 170 ± 10 U Si :195 ± 4 U, 98 ± 15 U Sd : 200 ± 3 U, 120 ± 14 U, especially the most remarkable decrease about 50 % in SHR innervated group.
Thus, according to these result, NO seems to maintain the MBF and the partial interaction between renal sympathetic nerve and NO in medullary blood flow can be suggested in innervated SHR.