[Difference in the expression of Kv channel in lymphocytes between spontaneously hypertensive rats and Wistar rats]

The present study aimed to investigate the difference in the voltage dependent potassium channel (Kv) expression in lymphocytes between the spontaneously hypertensive rats (SHRs) and Wistar rats. Peripheral blood lymphocytes were collected from 10 male SHRs and 10 normotensive Wistar rats aged 16 weeks. First, by using the patch-clamp technique, Kv channel current was recorded in freshly isolated lymphocytes from SHRs and normotensive Wistar rats. Total RNAs were extracted from lymphocytes by using TRIzol reagent. Real-time PCR was used to determine the expression of Kv1.3 mRNA and Western blot technique was used to measure the expression of Kv1.3 protein in lymphocytes from SHRs and normotensive Wistar rats. The results showed that: (1) The current density of Kv channel in the step voltage of +60 mV was higher in lymphocytes from SHRs than that from the normotensive Wistar rats [(119+/-10) pA/pF vs (56+/-9) pA/pF, P<0.05]; (2) The level of Kv1.3 mRNA expression in lymphocytes from SHRs was significantly increased compared with that of the normotensive Wistar rats (0.0313+/-0.017 vs 0.0023+/-0.005, P<0.05); (3) The expression of Kv1.3 protein was significantly elevated in lymphocytes (1.02+/-0.04 vs 0.41+/-0.03, P<0.05) from SHRs compared with that of the normotensive Wistar rats. The results obtained demonstrate that the lymphocytes Kv channels are increased in SHR, and the Kv channel may be involved in activation of lymphocytes from SHR.