Interrelation between the hypothalamic arcuate nucleus and the bone variation of osteoporosis in rats / 生理学报

This study investigated the interrelation between the hypothalamic arcuate nucleus (ARC) and the bone variation of osteoporosis in rats. Four animal models of ovariectomy-induced osteoporosis (OVX), glucocorticoid-induced osteoporosis (GIOP), retinoic acid-induced osteoporosis (RAOP) and senile osteoporosis (SOP) were used to study the influence of osteoporosis on ARC. Ovariectomized rats were further treated with thymopeptide, ciclosporin and exercise respectively to detect the changes of ARC nerve cells number. The results showed that: (1) The OVX, GIOP, RAOP and SOP models were successfully established, showing osteoporosis as well as decrease of the number of ARC nerve cells; (2) Thymopeptide and exercise respectively alleviated the bone loss induced by ovariectomy, accompanied by increase of the number of ARC nerve cells, while ciclosporin further increased the bone loss of ovariectomized rats, accompanied by further decrease of the number of ARC nerve cells. These results suggest that there is a close interrelationship between ARC and osteoporosis in rat. There is a hypothalamus-pituitary-bone (HPB) axis, and HPB axis regulates the mechanism of osteoporosis in rats.

Relationship between the levels of sex hormones and loss of bone mass in aging male rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the level of sex hormones and the loss of bone mass in aging male rats.</p><p><b>METHODS</b>Thirty male Sprague-Dawley rats were equally divided into five age groups and sacrificed at 35, 70, 160, 700 and 800 postnatal days (PD) , followed by measurement of the % Tb x Ar, Tb x Th, Tb x N and Tb x SP by bone histomorphometry and detection of the levels of serum testosterone (T) and estradiol (E2) by radioimmunoassay. The relationship between the changes of the T and E2 levels and those of bone histomorphometry was analyzed.</p><p><b>RESULTS</b>T and E2 levels were closely correlated with the bone mass in the aging male rats. The changes in T and E2 levels were simultaneous with those in the bone mass with the growth of the rats. T, E2, % Tb x Ar and Tb x N reached the peak in the 70 and 160 PD groups, and markedly decreased in the 700 PD group except Tb x Th and Tb x SP. The T levels in the 35, 70, 160, 700 and 800 PD groups were (118.53 +/- 18.35) ng/dl, (345.49 +/- 54.63) ng/dl, (368.83 +/- 60.03) ng/dl, (61.15 +/- 21.12) ng/dl and (60.35 +/- 19. 27) ng/dl, changing simultaneously with the E2 levels, which were (10.35 +/- 1.82) pg/ml, (16.92 +/- 3.13) pg/ml, (17.20 +/- 2.51) pg/ml, (5.87 +/- 2.34) pg/ml and (5.53 +/- 2.48) pg/ml, respectively. The metrological parameters of the bone structure in the five groups were as follows, Tb x Ar: (19.52 +/- 2.23)%, (26.28 +/- 2.18) %, (28.37 +/- 1.21) %, (15.62 +/- 1.68) % and (14.21 +/- 0.89) %; Tb x Th: (35.45 +/- 1.63) microm, (50.13 +/- 3.58) microm, (60.23 +/- 8.25) microm, (75.62 +/- 9.72) microm and (78.78 +/- 11.21) microm; Tb x N: (5.98 +/- 1.21) n/mm, (8.07 +/- 0.86) n/mm, (8.30 +/- 1.22) n/mm, (2.63 +/- 1.35) n/mm and (2.48 +/- 1.62) n/mm; Tb x SP: (126.34 +/- 18.15) microm, (136.26 +/- 15.27) microm, (261.08 +/- 76.43) microm, (323.12 +/- 78.12) microm and (330.23 +/- 50.20) microm.</p><p><b>CONCLUSION</b>Changes in the levels of sex hormones are closely correlated with those of bone mass. Both testosterone and estradiol are essential for bone development and bone mass maintenance.</p>

Mechanism of the influence of CCE3 on bone mineral element metabolism in ovariectomized rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the influence of CCE3 on bone mineral element metabolism and relative hormone in ovariectomized rats.</p><p><b>METHODS</b>24 female SD rats were divided randomly into 4 groups (n = 6): (1) Normal control; (2) sham ovariectomy; (3) ovariectomy(OVX); (4) OVX + CCE3.</p><p><b>RESULTS</b>(1) Ca, Mg, S, Co, Mn, Zn reduced obviously and P increased in the bone of the OVX rats. (2) E2, P, TSH, T4, CT, cortisol, GH reduced obviously and IL-6, FSH, LH increased obviously in serum of the OVX rats. (3) CCE3 corrected the changes of Ca, Mg, S, Co, Mn, Zn and P in bone as well as the changes of E2, P, TSH, T4, CT, cortisol, GH and IL-6, FSH, LH in serum of the OVX rats.</p><p><b>CONCLUSION</b>Changes of relative hormone and IL-6 induced by CCE3 are the important mechanism of the influence of CCE3 on bone mineral element metabolism in ovariectomized rats.</p>

Effect of exercise on bone mineral element metabolism and relative hormones in ovariectomized rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effect of exercise on bone mineral element metabolism and relative hormones in ovariectomized rats.</p><p><b>METHODS</b>24 female SD rats were divided randomly into 4 groups: (1) normal control, (2) sham ovariectomy, (3) ovariectomy (OVX), (4) OVX + exercise.</p><p><b>RESULTS</b>(1) Ca, Mg, S,Co,Mn, Zn reduced obviously and P increases in bone of the OVX rats. (2) E2, P, TSH, T4, CT, Cortisol, GH reduced obviously and IL-6, FSH, LH increased obviously in serum of the OVX rats. (3) Exercised opposed the changes of Ca, Mg, S, Co, Mn, Zn and P in bone as well as the changes of E2, P, TSH, T4, CT, Cortisol, GH and IL-6, FSH, LH in serum of the OVX rats.</p><p><b>CONCLUSION</b>Exercise may correct the changes of bone mineral element and the relative hormones in ovariectomized rats.</p>

The effect of hypothalamic arcuate nucleus damaged by monosodium glutamate on skeleton in rat / 中国应用生理学杂志

<p><b>AIM</b>To explore the effect of hypothalamic arcuate nucleus (ARC) on the skeleton in rat.</p><p><b>METHODS</b>Newborn SD rats were injected by 10% MSG 4 g/kg hypodermically once every other day until the 10th day postnatally, meanwhile, the newborn rats in control group were given by equal volume of normal saline. After surviving for 200 days, 6 female rats in each group were killed and their hypothalami were made into sections (4 microm) and stained with HE. The length, diameter, weight and volume of the femora, the tibia, the humeri, the radii and the ulnae were measured.</p><p><b>RESULTS</b>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/cm3) 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.</p><p><b>CONCLUSION</b>The hypothalamic arcuate nucleus participated in the regulation of the growth and development of skeleton in rats.</p>