【摘要】 目的:研究损毁下丘脑弓状核对大鼠骨组织形态计量学的影响。方法: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,并设MSG毒性对照组,于70 d龄同法注射MSG,各组大鼠皆存活至160 d。用3%戊巴比妥钠腹腔麻醉,用4%多聚甲醛经左心室行全身灌注,取脑作下丘脑弓状核冠状面切片,HE染色。取右侧胫骨常规脱钙,石蜡包埋,矢状面连续切片,胶原特殊染色,用于显示骨小梁结构。HE染色用于破骨细胞计数。图像分析仪对弓状核正中隆起切面和骨组织进行照片和计量。用放免法测血清中GH(生长素)、E2(雌二醇)和T(睾酮)含量。结果:MSG大鼠弓状核神经细胞数量显著减少,GH和E2、T水平明显降低,骨量显著减少,发生骨质疏松,NS组和MSG毒性对照组弓状核、GH、E2、T和骨组织无明显改变。结论:①MSG大鼠骨组织的改变不是MSG对垂体和骨组织的毒性作用所致;②下丘脑弓状核参与骨代谢的调控;③通过GH和性激素作用是ARC参与骨代谢调控的重要途径。更多还原

【Abstract】 AIM: To investigate the effect of hypothalamic arcuate nucleus(ARC) damaged by monosodium glutamate(MSG) on bone histomorphometry parameters in rats.METHODS:(1) Newborn SD rats of experimental group were hypodermically injected 10% MSG(4 g/kg BW) on the postnatal lst,3rd,5th,7th,9th day.Meanwhile,the newborn rats of the control group were given equal volume of normal saline and the rats after the postnatal 70th,72th,74th,76th and 78th day were hypodermically injected 10% MSG(4 g/kg BW) as the MSG toxicity control group.After survivial for 160 days,all rats were killed.(2) Morphological methods were used to estimate the ARC neurons and the bone histomorphometry parameters.(3) Radioimmunoassay was used to measure the levels of the serum growth hormoen(GH),estradiol(E2) and testosterone(T).RESULTS: The number of the hypothalamic arcuate nucleus neurons,the levels of serum E2,T,GH and the %Tb·Ar,Tb·Th,Tb·N of proximal tibial metaphysis(PTM) significantly decreased,while Tb·Sp of proximal tibial metaphysis(PTM) significantly increased,and the osteoporotic alterations appeared obviously.All these changes did not appear in the rats of NS group and MSG toxicity control group.CONCLUSION:(1) The changes of the bone in MSG guoup rats are not the effect of the MSG toxicity on the bone directly.(2) The hypothalamic arcuate nucleus participates in the regulation of the bone metabolism.(3) ARC regulates bone metabolism via altering the functions of the hypothalamus-GH-IGF-1 axis and the hypothalamus-pituitary-gonal axis.更多还原