目的:探讨绝对不应期电刺激(ARPES)对正常豚鼠和慢性心力衰竭(衰竭)豚鼠心窀肌细胞动作电位(AP)及钠离子—钙离子(Na^+-Ca^(2+))交换的影响。方法:应用膜片钳技术中电流钳记录 ARPES 对 AP 时程的影响,再以不同的 AP 电压钳记录细胞膜 N...目的:探讨绝对不应期电刺激(ARPES)对正常豚鼠和慢性心力衰竭(衰竭)豚鼠心窀肌细胞动作电位(AP)及钠离子—钙离子(Na^+-Ca^(2+))交换的影响。方法:应用膜片钳技术中电流钳记录 ARPES 对 AP 时程的影响,再以不同的 AP 电压钳记录细胞膜 Na^+-Ca^(2+)交换电结果:①ARPES 延长 AP 时程,以 APD_(30)最为显著(P<0.01),差异有统计学意义。②与正常豚鼠心室肌细胞比较,衰竭豚鼠心室肌细胞 AP 的平台期明显不同,表现在 APD_(90)变化(P<0.05)及 APD_(50)变化(P<0.01),差异有统计学意义。③分别以基础刺激(S_t)下的 AP(AP_(S1))和 ARPES 下的 AP(AP_(ARPES))为测试电压,记录 AP 电压钳下的细胞膜 Na^+-Ca^(2+)交换电流,在正常豚鼠心空肌细胞,AP_(ARPES)电压钳记录的单位膜电容下的外向电流强度的帑合值高于 AP_(S1)电压钳记录的相应值,而单位膜电容下的内向电流强度的整合值无显著变化。在衰竭豚鼠心室肌细胞,AP_(ARPES)电压钳记录的单位膜电容下的外向电流强度的整合值明显高于 AP_(S1)电压钳记录的相应值,而单位膜电容下的内向电流强度的整合值无显著变化。外向电流峰值的增加更为明显。结论:ARPES 延长正常豚鼠和衰竭豚鼠心室肌细胞 AP 时程,对心室肌细胞膜 Na^+-Ca^(2+)交换电流的影响可能是其增强整体心脏收缩功能的机制之一。展开更多
Objective To observe the effects of methionine enkephalin (M Enk) on migration of macrophages from mice with impaired liver and its immunomodulatory mechanisms. Methods Liver of mice was impaired by feeding CCl 4 and ...Objective To observe the effects of methionine enkephalin (M Enk) on migration of macrophages from mice with impaired liver and its immunomodulatory mechanisms. Methods Liver of mice was impaired by feeding CCl 4 and macrophage migration inhibitory factor (MMIF) was produced by Con A stimulated spleen lymphocytes. Inhibition of macrophage migration was measured in reaction system by adding M Enk. Results Migration of macrophages in both liver impaired and control group were suppressed by MMIF, but the suppression might be reversed by adding 1 μmol/L M Enk ( P <0.05).M Enk could significantly inhibit in vitro both of the combination of MMIF with macrophages and production of MMIF from lymphocytes ( P <0.01).Macrophages from liver imparied group showed a higher sensitivity compared to the control group ( P <0.05).Conclusion The study suggests that opioid peptieds play an important role in the modulation of the immune response under stress as liver impairment.展开更多
文摘目的:探讨绝对不应期电刺激(ARPES)对正常豚鼠和慢性心力衰竭(衰竭)豚鼠心窀肌细胞动作电位(AP)及钠离子—钙离子(Na^+-Ca^(2+))交换的影响。方法:应用膜片钳技术中电流钳记录 ARPES 对 AP 时程的影响,再以不同的 AP 电压钳记录细胞膜 Na^+-Ca^(2+)交换电结果:①ARPES 延长 AP 时程,以 APD_(30)最为显著(P<0.01),差异有统计学意义。②与正常豚鼠心室肌细胞比较,衰竭豚鼠心室肌细胞 AP 的平台期明显不同,表现在 APD_(90)变化(P<0.05)及 APD_(50)变化(P<0.01),差异有统计学意义。③分别以基础刺激(S_t)下的 AP(AP_(S1))和 ARPES 下的 AP(AP_(ARPES))为测试电压,记录 AP 电压钳下的细胞膜 Na^+-Ca^(2+)交换电流,在正常豚鼠心空肌细胞,AP_(ARPES)电压钳记录的单位膜电容下的外向电流强度的帑合值高于 AP_(S1)电压钳记录的相应值,而单位膜电容下的内向电流强度的整合值无显著变化。在衰竭豚鼠心室肌细胞,AP_(ARPES)电压钳记录的单位膜电容下的外向电流强度的整合值明显高于 AP_(S1)电压钳记录的相应值,而单位膜电容下的内向电流强度的整合值无显著变化。外向电流峰值的增加更为明显。结论:ARPES 延长正常豚鼠和衰竭豚鼠心室肌细胞 AP 时程,对心室肌细胞膜 Na^+-Ca^(2+)交换电流的影响可能是其增强整体心脏收缩功能的机制之一。
文摘Objective To observe the effects of methionine enkephalin (M Enk) on migration of macrophages from mice with impaired liver and its immunomodulatory mechanisms. Methods Liver of mice was impaired by feeding CCl 4 and macrophage migration inhibitory factor (MMIF) was produced by Con A stimulated spleen lymphocytes. Inhibition of macrophage migration was measured in reaction system by adding M Enk. Results Migration of macrophages in both liver impaired and control group were suppressed by MMIF, but the suppression might be reversed by adding 1 μmol/L M Enk ( P <0.05).M Enk could significantly inhibit in vitro both of the combination of MMIF with macrophages and production of MMIF from lymphocytes ( P <0.01).Macrophages from liver imparied group showed a higher sensitivity compared to the control group ( P <0.05).Conclusion The study suggests that opioid peptieds play an important role in the modulation of the immune response under stress as liver impairment.
