缺氧对离体猫心乳头肌力学的影响

本文研究缺氧对离体猫心乳头肌力学的影响,以探讨缺血性心肌损伤中缺氧这一因素所起的作用。结果表明:①-dT/dt max/Tmax(舒张指标之一)在缺氧 lmin 时明显降低(P<0.05),而所有收缩指标无变化。②缺氧4min 时,-dT/dt max 降低16.7%(P<0.01),而 dT/dt max 在缺氧7min 时才降低16.6%(P<0.05)。③在缺氧4min 时,所有舒张指标已发生显著的变化,而所有收缩指标在缺氧7min 时才有明显改变。缺氧对离体猫心乳头肌的收缩过程和舒张过程都有影响,但是舒张过程的变化较之收缩过程出现更早,且较明显。

EFFECTS OF HYPOXIA ON MECHANICAL PROPERTIES OF ISOLATED CAT PAPILLARY MUSCLE

The mechanical properties of isolated cat papillary muscle were investigatedduring hypoxia and after reoxygenation.The results showed that-dT/dt max/Tmax,one of the relaxation parameters,decreased significantly after 1 min hypoxia,while all the other contraction parameters remained unchanged.-dT/dt max dec-reased to 16.7%(P<0.01)after 4 min hypoxia,while the time needed for dT/dtmax decreased to the same extent(16.6%,P<0.05)was 7 min.All relaxation para-meters changed significantly for a point of 4 min hypoxia,but the changes of con-traction parameters were delayed only after 7 min hypoxia.It is concluded thatboth contraction and relaxation processes of isolated cat papillary muscle are affectedby hypoxia,in which the change of relaxation process begins to appear earlier andmore prominent than that of contraction process.