镧对大白鼠离体回肠运动的影响

采用37℃恒温平滑肌槽灌流法,通过BL-410生物机能实验系统观察并记录氯化镧、氯化钙、阿托品、酚妥拉明对大鼠离体回肠运动的影响。结果表明:稀土La对大鼠离体回肠运动有明显的抑制作用;在回肠平滑肌细胞外液中,La3+和Ca2+之间存在竞争性拮抗作用;La3+可减少Ca2+内流,使平滑肌兴奋-收缩耦联机制减弱,导致收缩振幅减小;同时La3+,使平滑肌的基本电节律变慢,导致收缩频率减小;La对回肠运动的抑制作用可能与回肠平滑肌上的胆碱能M受体和肾上腺素能α受体都无关。

Effect of Lanthanum on Activity of Isolated Rat's Ileum

To explore the effect and mechanisms of rare earth La on the activity of isolated rat's ileum,the investigation and the recording of the effects of LaCl3 and CaCl2,atropine and phentolamine on the activity of isolated rat's ileum were performed by the perfusion with 37°C temperature-keeping smooth muscle bath and BL-410 experimental system of biological function. The results indicated that rare earth La could significantly inhibit the activity of isolated rat's ileum. There was a competitive antagonism between La3+ and Ca2+ in the intracellular fluid of the ileum smooth muscle. Possibly La inhibited the contractile amplitude of isolated rat's ileum by weakening the excitation-contraction coupling was due to the decrease of the inflow of Ca2+ and decreased the contractile frequency by slowing the basic electrical rhythm was due to the increase of the membrane potential. Probably the inhibitory effect of La had no relation to M receptors and α receptors on the smooth muscle cells of the ileum.