The surface expressions of T lymphocyte subtypes, Cx40/Cx43, and inflammatory cytokines (IFN-γ (interferon-gamma) and TNF-ɑ (tumor necrosis factor alpha)) in T cells, as well as gap junction communication of peripheral blood lymphocytes from essential hypertensive patients (EHs) and normotensive healthy subjects (NTs) were detected by flow cytometry. Here, TNF is linked to essential hypertension.