摘要
目的观察冷应激条件对大鼠血压的影响,并探讨低温条件下血管平滑肌细胞(VSMC)大电导钙激活钾通道电流(BKCa)的改变。方法健康成年SD大鼠30只,完全随机分为对照组和实验组,实验组又分为2、4、6、8周组,每组6只。建立冷应激大鼠高血压模型,采用全细胞膜片钳技术记录大鼠主动脉VSMC膜BKCa电流。结果实验组大鼠血压从第2周开始升高,2、4、6、8周组的大鼠血压较正常组分别增加了17.60%、28.51%、36.97%、52.01%。全细胞膜片钳技术记录显示冷应激大鼠主动脉VSMC膜BKCa电流和电流密度随冷应激时间延长而增大,2、4、6、8周组大鼠BKCa电流密度较正常组分别增加73.99%、165.91%、271.34%、346.35%。结论冷应激环境的刺激可致大鼠血压升高和BKCa电流密度增大,该变化随冷应激时间的延长而逐步加大,其机制可能是VSMCCa2+内流增加,导致血管收缩,血管阻力增加,血压升高。
Objective To observe the blood pressure and the current density of large-conductance calcium-activated potassium channel（BKCa） in vascular smooth muscle cells（VSMC） in cold-induced hypertensive rats.Methods Thirty adult SD rats were randomly divided into control and experimental group.The latter was subdivided into 2,4,6,8 week groups.We set up cold-induced hypertensive rats models and employed the whole-cell patch clamp recording technique to record the BKCa current of VSMC in those models.Results Compared with the control group,systolic blood pressures （SBP） of the rats exposed to cold for 2,4,6,8 weeks were increased by 17.60%,28.51%,36.97%,and 52.01%,respectively;The BKCa current and BKCa peak current density in aortic VSMC increased significantly as the time of exposure to cold went by.Compared with the control group,the BKCa peak current density in the cold-exposed group were increased by 73.99%,165.91%,271.34% and 346.35%,respectively at the 2th,4th,6th and 8th weeks.Conclusion Cold stress stimuli in the environment can cause the increases of blood pressure and BKCa current density,and the changes can be more significant with longer exposure to cold stress.The mechanism may be that increased VSMC Ca2＋ in internal flow leads to contraction of blood vessels,increased vascular resistance and therewith increased blood pressure..
出处
《中华高血压杂志》
CAS
CSCD
北大核心
2010年第9期837-840,共4页
Chinese Journal of Hypertension
基金
国家科技支撑计划(2008BAI68B02)
关键词
冷应激性高血压
膜片钳
血管平滑肌细胞
大电导钙激活钾通道
Cold-induced hypertension
Patch clamp
Vascular smooth muscle cell
High-conductance calcium-activated potassium channels
