氟化钠急性中毒对小白鼠肠系膜微血管的影响

ACUTE FLUOROSIS OF THE MOUSE MESENTERIC VASCULAR BED

本实验观察了氟化钠(NaF)急性中毒后的一段时间内小白鼠肠系膜微血管对作为交感神经兴奋递质的去甲肾上腺素(NE)收缩反应性的改变,以加深对NaF中毒后的肠微循环损伤机理的认识。 用半数致死量的NaF经胃给空腹小白鼠染毒,然后分别在染毒后半小时及1.5～60小时内用1‰及1％浓度的NE直接灌注小白鼠肠系膜,动态观察肠系膜细动脉、细静脉内径大小的变化,同时与未染毒但给予同样二种浓度的NE肠系膜灌注的对照组动物(为染毒半小时动物的自身前后实验对照;染毒1.5～60小时动物的实验对照)肠系膜细动脉、细静脉内径大小变化作比较。结果发现,二种浓度NE灌注肠系膜,染毒半小时动物的细动脉、细静脉对此二种浓度NE的收缩反应性与自身前后对照组动物相比无显著差异,染毒1.5～60小时动物细动脉、细静脉对这二种浓度NE仍有明显收缩反应性;但均低于相应的正常实验对照组。同时,这种降低了的收缩反应性与细血管种类及NE浓度有关,即二种细血管对1％NE的收缩反应性大于对1‰NE的收缩反应性,细静脉对1‰NE的收缩反应性大于细动脉对1‰NE的收缩反应性。

In this experiment we observed the contractive reactivity of the mesenteric microvessels of the mice poisoned by LD50 sodium fluoride(NaF) . Our results showed; after the mice were poisoned 0.5h, the contractive reactivity of the fine arteriole and venules of the mice were nearly normal to both 1% and 1% noradrenaline (NE) . After 1.5-60h, the two kinds of the microvessels had still clear contractive reactivity to NE, but this reactivity was lower than normal and varied with the kinds of mesenteric microvessels and levels of NE.