초산납이 흰쥐 synaptosome의 [3H]-serotonin의 흡수에 미치는 영향

초록

This study was carried out to investigate the physiological changes induced acutely with the low doses of lead acetate in the synaptosomes from the cerebrum and brain stem of the rat. The general uptake patterns of [^3H]-serotonin were observed in synaptosomes, as a model of presynaptic nerve terminal, from the cerebrum and brain stem. And the effects of the low doses of lead acetate on the uptake process were investigated in vitro and in vivo. The Km value of the uptake of the [^3H]-serotonin by the synaptosomes was 0.5μM in the cerebrum and 0.1μM in the brain stem. These low values reveal that the synaptosomes from the cerebrum and the brain stem have a high affinity to [^3H]-serotonin, especially in brain stem. The uptake of [^3H]-serotonin was dependant on the sodium and potassium ions. When being treated with ouabain, the Na^+-K^+ ATPase inhibitor, the uptake of [^3H]-serotonin was reduced. This supports strongly that the uptake of [^3H]-serotonin was sensitive to the changes of the concentrations of the sodium and potassium ions. When the calcium channel blocker, verapamil, was treated, the uptake of [^3H]-serotonin was changed only in synaptosomes from the brain stem. The uptake of [^3H]-serotonin was reduced by the lead treatment in the synaptosomes from the cerebrum and brain stem in vitro and in vivo. [lead acetate, synaptosomes, [^3H]-serotonin, rat]