Study on changes of plasma substance p in essential hypertension with left ventricular hypertrophy patients and the effects of promoting blood circulation and eliminating phlegm

Left Ventricular hypertrophy (LVH) is a common complication of essential hypertension (EH). Substance P (SP) is a protective substance of myocardium. The purposes of this study were to explore the relationship between the plasma SP and EH with LVH (EH-LVH) and the effect of promoting blood circulation and eliminating phlegm (PBCEP) on EH-LVH. The study group consisted of 30 patients with EH and 20 normotensive control subjects. Patients with EH were divided into two groups: 15 patients with LVH and 15 without LVH (EH-NLVH). Patients with EH-LVH were not treated by antihypertensive drugs two weeks before the test. PBCEP consists of salviae miltiorrhizae 10 g, ligustrazine 15 g, astragali 15 g, hematite 20 g, achyranthes bidentata blume 15 g, Pinellia ternate 15 g, ilex pubescens hook 20 g, macrostemon bunge 15 g and cinnamomum 10 g. These drugs were decocted by water and taken orally once daily. The course of treatment is three months. Before and after treatment, the changes of SP in patients with EH-LVH were measured by radioimmunoassay. At the same time, the changes of plasma renin activity (PRA), angiotension II (Ang II), Left ventricular mass index (LVMI) and mean aterial pressure (MAP) were measured. We found that the level of plasma SP in patients with EH-LVH was markedly lower than that of patients with EH-NLVH and healthy subjects (p < 0.01); the levels of PRA and Ang II were higher than those in control group (P < 0.01, or < 0.05). The levels between SP and LVMI, MAP, PRA, Ang II were markedly negative correlated, (r = −0.714, −0.819, −0.681, −0.758, P < 0.01), while levels between LVMI and PRA, Ang II were markedly positive correlated (r = 0.814, 0.763, P < 0.01). These findings show that the SP may be involved in the pathogenesis of EH-LVH and the mechanism of PBCEP reversing LVH may be related to its increasing the plasma SP.