Effect of renal sympathetic denervation with different dose phenol on blood pressure in spontaneous hypertension rats

doi:10.3969/j.issn.1672-5301.2017.11.020

Abstract：Objective To investigate the impact of renal sympathetic denervation (RDN) with a suitable dosage of phenol on the blood pressure,plasma noradrenaline and renal nerves injury in spontaneous hypertension rats (SHRs).Methods Male SHRs were randomly divided into four groups:the 0.5 ml phenol group which was subjected to RDN at the age of 13 weeks;the 1.0 ml phenol group;1.5 ml phenol group and the Sham group which underwent the sham procedure(n=10,each group).Blood pressure was measured every week using the tailcuff plethysmography.Four weeks after the RDN or sham operation,plasma norepinephfine (NE) were assessed.Kidney artery and nerve tissue were collected and characterized by immunohistochemically analyses.Results Compared with Sham group,the 1.0 ml phenol group with RDN significantly attenuated the progressive increase in blood pressure [(163.60±5.87)mm Hg vs (193.70±6.07)mm Hg,P＜0.01] and decreased plasma NE level [(50.50±31.01)ng/L vs (197.50±35.27)ng/L,P＜0.01].The result of HE staining showed mild injury of renal artery in 1.0 ml phenol group and moderate to severe injury in 1.5 ml phenol group,while severe injury of renal nerves were occurred in 1ml phenol group and 1.5 ml phenol group.RDN treatment also inhibited the expression of tyrosine hydroxylase (TH) and increased the expression of neurofilament protein (NF200) in renal nerves in 1ml phenol group compared with sham group [TH score:0.51±0.30 vs 2.58±0.30,P＜0.01;NF200 score:2.27±0.30 vs 0.09±0.10,P＜0.01].Conclusion RDN with 1.0 ml phenol can effectively destroy the renal nerves without renal arterial stenosis and decrease blood pressure in SHRs,which might be associated with inhibition of expression of TH.