The action of serotonin on excitatory nerve terminals in lobster nerve-muscle preparations.

摘要: 1. The action of serotonin on excitatory transmission in the opener muscle dactyl lobster walking leg was examined by intracellular recording techniques. 2. Serotonin, at concentrations as low 5 x 10(-9) M, caused a sustained increase size junctional (synaptic) potential (e.j.p.). When washed out bath e.j.p. declined two steps (T 1/2 approximately equal to 1-2 min; T 30 min) control size. increased predominantly due serotonin-induced release quanta transmitter with nerve stimulation. 3. did not require stimulation or presence Na+ Ca2+ ions bathing medium during period treatment. 4. Three types experiments suggested that part terminals might involve long-term metabolic change within terminals, possibly involving buffering storage ions. First, frequency spontaneous both normal saline (26 mM-Ca2+) and very levels (less than 10(-8) M). Secondly, greatly potentiated increases miniature induced loading terminal either veratridine inhibition pump addition Na-ionophore monensin low-Ca2+ salines. Thirdly, some experiments, treatment produced partial restoration nerve-evoked