The movements of labelled phosphate were measured in garfish olfactory and in rabbit vagus nerves at rest and during activity. 2. In garfish olfactory nerve kept in solutions with 120 mM-sodium and 0.2 mM-phosphate the fractional loss of 32P was 9.82 X 10(-4) min-1. Lowering the sodium concentration of the washing fluid decreased the efflux; lowering the phosphate produced a transient increase with subsequent return towards the efflux in 0.2 mM-phosphate. 3. Stimulation at 0.50 sec produced an extra fractional loss of 12 X 10(-6) impulse-1. At 1/sec the effect was larger; at 5/sec it was about the same as at 0.5/sec. 4. After stimulation the effect of activity disappeared exponentially with a time constant of 4.4 min. 5. Lowering the sodium decreased the extra efflux with stimulation, whereas changing the phosphate concentration did not much affect the extra efflux. 6. In rabbit vagus nerve kept in 154 mM-sodium and 0.2 M-phosphate the fractional loss of 32P was 4.91 X 10(-4) min-1. Lowering the sodium or the phosphate decreased the resting efflux. 7. Stimulation of the vagus nerve at 15/sec produced an extra fractional loss of 0.87 X 10(-6) impulse-1. 8. The extra efflux with stimulation seems to result predominantly from an increase in intracellular inorganic phosphate resulting from increased break-down of ATP after activity.
摘要
对处于静息状态和活动状态的海鳗嗅神经以及兔迷走神经中标记磷酸盐的移动进行了测量。2. 在置于含120 mM - 钠和0.2 mM - 磷酸盐溶液中的海鳗嗅神经中，32P的分数损失为9.82×10(-4) min-1。降低冲洗液中的钠浓度会减少流出；降低磷酸盐浓度会产生短暂增加，随后又恢复到0.2 mM - 磷酸盐时的流出水平。3. 以0.50秒的频率刺激会产生额外的分数损失，为12×10(-6) 次冲动-1。频率为1/秒时效果更大；频率为5/秒时与0.5/秒时大致相同。4. 刺激后，活动的影响呈指数形式消失，时间常数为4.4分钟。5. 降低钠浓度会减少刺激时的额外流出，而改变磷酸盐浓度对额外流出影响不大。6. 在置于含154 mM - 钠和0.2 M - 磷酸盐溶液中的兔迷走神经中，32P的分数损失为4.91×10(-4) min-1。降低钠或磷酸盐会减少静息流出。7. 以15/秒的频率刺激迷走神经会产生额外的分数损失，为0.87×10(-6) 次冲动-1。8. 刺激时的额外流出似乎主要是由于活动后ATP分解增加导致细胞内无机磷酸盐增加所致。
