Direct measurement of flow from the posterior lymph hearts of hydrated and dehydrated toads (Bufo marinus).
Direct measurement of flow from the posterior lymph hearts of hydrated and dehydrated toads (Bufo marinus).
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直接测量水合和脱水蟾蜍（Bufo marinus）后部淋巴心脏的流量。
DOI：
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发表时间：
1997
影响因子：
2.8
通讯作者：
D. Toews
中科院分区：
文献类型：
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作者：
J. M. Jones;A. K. Gamperl;A. Farrell;D. Toews
用多普勒血流探头测量了海蟾蜍后淋巴心的血流。将这些探头放置在椎后静脉上，并记录淋巴液从心脏排出时的流量。在静息、水合蟾蜍中，来自成对后部淋巴心脏之一的平均淋巴流量为25.9 +/- 4.9 ml kg-1 h-1，每搏输出量为8.9 +/- 1.4 microL kg-1，淋巴心率为47.5 +/- 3.7次/min-1。我们估计，成对的后淋巴心能够产生大约是静息心输出量的六十分之一的流量。后淋巴心产生的平均峰值收缩压为1.62 +/- 0.08 kPa。淋巴心脏压力发展和流量的同时测量显示，心脏的流出孔在0.71 +/- 0.04 kPa的压力下打开，约113 +/- 5 ms进入收缩期。当蟾蜍受到中度干扰时，每搏输出量增加了4倍，而淋巴心率几乎没有变化（< 5次/min）。当蟾蜍脱水时，淋巴流量在12小时减少70%，在24小时减少80%。由于淋巴心率仅出现中度非显著性降低（30%），因此流量减少归因于每搏输出量减少（约80%）。将水重新加入实验室后30分钟，淋巴心流量和每搏输出量恢复至对照值。每搏输出量显然更重要的是在调节淋巴流量比淋巴心率在这些条件下，在蟾蜍marinus。
Flow from the posterior lymph hearts of Bufo marinus was measured using Doppler flow probes. These probes were placed on the posterior vertebral vein and recorded flow as lymph was ejected from the heart. In resting, hydrated toads, mean lymph flow from one of the paired posterior lymph hearts was 25.9 +/- 4.9 ml kg-1 h-1, stroke volume was 8.9 +/- 1.4 microL kg-1 and lymph heart rate was 47.5 +/- 3.7 beats min-1. We estimate that, together, the paired posterior lymph hearts are capable of generating flows that are approximately one-sixtieth of the resting cardiac output. Mean peak systolic pressure developed by the posterior lymph hearts was 1.62 +/- 0.08 kPa. Simultaneous measurements of lymph heart pressure development and flow revealed that the outflow pore of the heart opened at a pressure of 0.71 +/- 0.04 kPa, approximately 113 +/- 5 ms into systole. When toads were moderately disturbed, stroke volume increased by as much as fourfold with little change in lymph heart rate (< 5 beats min-1). When toads were dehydrated, lymph flow decreased by 70% at 12h and by 80% and 24h. Since there was only a modest non-significant decrease in lymph heart rate (30%), this reduction in flow was attributed to decreases in stroke volume (approximately 80%). Lymph heart flow and stroke volume returned to control values 30 min after adding water back into the experimental chamber. Stroke volume was clearly more important in regulating lymph flow than lymph heart rate under these conditions in Bufo marinus.