Effects of telmisartan on 4-Aminopyridine-sensitive voltage dependant potassium channel of lymphocyte derived from spontaneously hypertensive rat / 中华心血管病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To study the effects of telmisartan on voltage dependant potassium channel (Kv) expression in lymphocytes from spontaneously hypertensive rat (SHR).</p><p><b>METHODS</b>Peripheral blood was collected from male SHR aged 16 and 4 weeks. Peripheral lymphocytes were separated from heparinized whole blood by standard Ficoll-Hypaque density gradient centrifugation. The whole-cell Kv currents were recorded with patch-clamp technique in the absence and presence of telmisartan(10, 30, 100 µmol/L). Real-time PCR was used to determine Kv1.3 mRNA expression in lymphocytes.</p><p><b>RESULTS</b>(1) The currents density of Kv was higher in lymphocytes from 16 weeks-old SHR [ (119.0 ± 9.6) pA/pF] than from 4 weeks-old SHR [(59.0 ± 7.2) pA/pF, P < 0.05]. (2) Currents density was positively correlated with systolic blood pressure in 16 weeks-old SHR (r = 0.837, P < 0.05). (3) The lymphocytes Kv 1.3 mRNA expression was significantly higher in 16-weeks-old SHR than in 4-weeks-old SHR (P < 0.05). (4) Telmisartan reduced the whole-cell Kv currents in a concentration-dependent manner (10.5 ± 3.4)% at 10 µmol/L, (45.8 ± 3.7)% at 30 µmol/L and (81.6 ± 4.2)% at 100 µmol/L, P < 0.01.</p><p><b>CONCLUSIONS</b>The lymphocyte Kv channel is upregulated in 16 weeks-old SHR suggesting a role of Kv in the pathophysiology of hypertension. Kv current in lymphocyte could be significantly blocked by telmisartan in a concentration dependent manner.</p>