Expression Of Kv1.3Potassium Channels In CD4~+T Cells In Peripheral Blood Of Patients With Hypertension

Objective: To explore the changes of voltage-gated potassium channels (Kv1.3) inCD4~+T lymphocytes in peripheral blood of patients with hypertension, and how doesAngiotensin Ⅱ (AngⅡ) participate in the inflammatory reaction of lymphocytes involved inhypertension.Methods: CD4~+T cells in24hypertension patients and24healthy volunteers wereisolated from peripheral blood with magnetic cell sorting, and trained respectively with0,2nmol/L AngⅡ for48h. The Kv1.3channel current and membrane capacitance of differentgroups were recorded by whole-cell patch-clamp technique. mRNA expression of Kv1.3potassium channels and angiotensin receptor (AT1R) were detected by Real-timequantitative PCR, and the concentration of interferon gamma (IFN-γ) in culture supernatantwere determined by ELISA kit.Results:(1) Peak Kv1.3channel current and membrane capacitance of CD4~+T cells inhypertension patients was significantly higher than that in healthy volunteers. Whencorrected by membrane capacitance, there was no significant difference betweenhypertension patients and healthy volunteers.(2) After exposure to AngⅡ, the membranecapacitance of CD4~+T lymphocytes did not change in both hypertensive patients andhealthy volunteers; Both peak current and current density of CD4~+T cell Kv1.3potassiumchannels increased significantly in healthy volunteers after co-culture with AngⅡ, whilethere was no obvious change in hypertension patients.(3) Before intervention with AngⅡ, Kv1.3potassium channels’ mRNAs expression of CD4~+T cells made no differencesbetween hypertensive patients and healthy volunteers; After intervention with AngⅡ,expression of mRNAs for Kv1.3potassium channels increased significantly in healthyvolunteers,which didn’t show markedly increase in hypertensive patients.(4) we detectedthe mRNAs expression of angiotensin receptor (AT1R) on human CD4+T lymphocytes,and found that expression of mRNAs for AT1R on CD4~+T cells in hypertension patientswas apparently more than that in healthy volunteers.(5)Moreover, compare with healthyvolunteers, concentration of IFN-γ in culture supernatant increased markedly inhypertension patients after co-culture with AngⅡ.Conclusions: In contrast to healthy volunteers, CD4~+T cells in hypertension patientsexpressed more Kv1.3potassium channels. AngⅡ can enhance the expression of Kv1.3potassium channels. Furthermore, AngⅡ can promote activation and IFN-γ secretion ofCD4~+T cells, which may be mediated by AT1R. This study indicates that inflammation isinvolved in the pathogenesis of hypertension and its target organ damage, and Kv1.3potassium channel plays an important role in the inflammation development ofhypertension.