Neuromuscular Facilitation in Crayfish: Dependence on Potassium and Strophanthidin
نویسنده
چکیده
1. Long-term facilitation (LTF) and short-term facilitation (STF) at excitatory neuromuscular junctions were studied under conditions of varying [K]o and with the addition of strophanthidin. 2. The magnitude of LTF varied inversely with [K+]o, while STF was unaffected. 3. Strophanthidin concentrations greater than io" M greatly increased LTF, but not STF. 4. Both LTF and STF were unaffected by large decreases in excitatory junctional potential amplitude produced by the addition of GABA or Mn. 5. The results support the hypothesis that LTF is a consequence of Na accumulation in presynaptic terminals and behaves independently of STF.
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تاریخ انتشار 2005