新生期注射谷氨酸单钠对大鼠骨骼的影响

THE EFFECT OF HYPOTHALAMIC ARCUATE NUCLEUS DAMAGED BY MONOSODIUM GLUTAMATE ON SKELETON IN RAT

目的:探讨下丘脑弓状核对大鼠骨骼的影响。方法:用损毁弓状核(ARC)的方法,将SD大鼠于出生后第1、3、5、7、9 d皮下注射10%谷氨酸单钠(MSG)4 g/kg bw,对照组同法注射等体积生理盐水,存活至第200 d处死,剥净左侧股、胫、肱、桡、尺骨,测其重量、长度、横长径、横短径、体积。下丘脑作石蜡切片,HE染色,光镜观察ARC神经元,并用图像分析仪计算ARC神经细胞数。用放免法测血清中GH(生长素),E2(雌二醇)含量。结果:MSG大鼠弓状核神经细胞数量显著减少,股、胫、肱、桡、尺骨的重量、长度、横长径、横短径、体积都明显减少,与对照组比较差异非常显著(P<0.01)。但单位体积骨重量(g/cm3)与对照组差异不显著。血清GH、E2显著降低。结论:提示下丘脑弓状核通过调节与骨代谢有关的激素参与全身骨骼生长发育的调控。

Aim： To explore the effect of hypothalamic arcuate nucleus（ARC） on the skeleton in rat. Methods： Newborn SD rats were injected by 10% MSG 4g/kg hypodermically once every other day until the 10th day posmatally, meanwhile, the newborn rats in control group were given by equal volume of normal saline. After surviving for 200 days i 6 female rats in each group were killed and their hypothalami were made into sections（4 μm） and stained with HE. The length, diameter, weight and volume of the femora, the tibia, the humeri, the radii and the ulnae were measured. Results： The number of the hypothalamic arcuate nucleus nervous cell were obviously less than those in control group as well as the length, diameter, weight, volume but the weight/volume （g/cm^3） of the femora, the tibia, the humeri, the radii and the ulnae decreased significantly as compared with the control group. Levels of serum GH E2 in rats of MSG group were obviously lower than that in control group. Conclusion： The hypothalamic arcuate nucleus participated in the regulation of the growth and development of skeleton in rats.