A Differential Effect of Thyroxine and Glucocorticoids on Fetal Brain and Heart Insulin Receptor
A Differential Effect of Thyroxine and Glucocorticoids on Fetal Brain and Heart Insulin Receptor
复制标题
甲状腺素和糖皮质激素对胎儿脑和心脏胰岛素受体的差异作用
作者：
S. Devaskar;P. Grim;U. Devaskar
摘要：研究甲状腺素（T4）、糖皮质激素和T4 +糖皮质激素对胎兔脑和心脏胰岛素受体成熟的影响。母鼠连续10天给予5剂T4（每剂50 μg/kg体重）；大量的[125I]胰岛素通过胎盘（胎血清游离T4 = 0.75±0.08，对照组为0.21±0.02 ng/dl, p < 0.02），使[125I]胰岛素对30日龄胎心膜的特异性结合从对照组的每100 μg蛋白3.6±0.74%增加到5.8±0.19% （p < 0.05）。曲线Scatchard图显示，受体数量× 107 μg protein-1从137±4增加到244±39 (p < 0.05)，而受体亲和力没有变化。未发现T4对30天胎儿脑[125I]胰岛素特异性结合和受体数量的明显改变。t4组胎心糖原含量降低，血浆葡萄糖浓度小幅升高（p < 0.02）。0.17 mg/kg倍他米松不影响[125I]胰岛素与27日龄胎儿心脏或脑质膜的特异性结合，但观察到心脏糖原含量降低，血浆葡萄糖浓度升高（p < 0.02）。此外，T4 +倍他米松不会改变[125I]胰岛素与27天胎儿心脏或脑质膜的结合，但会导致心糖原的累加效应（显著耗损）（p < 0.001）。脑糖原在所有胎儿中都检测不到，对照组和治疗组（不管激素治疗的类型）。因此，T4和糖皮质激素对发育中的胎儿大脑和心脏胰岛素受体产生不同的影响，同时消耗心肌糖原储存。
ABSTRACT: We investigated the effect of thyroxine (T4), glucocorticoids, and T4 + glucocorticoids on the maturation of fetal rabbit brain and heart insulin receptors. Five doses of T4 over 10 days (50 μg/kg body weight per dose) were administered to the mother; significant amounts crossed the placenta (fetal serum free T4 = 0.75 ± 0.08 versus a control of 0.21 ± 0.02 ng/dl, p < 0.02) and increased the specific binding of [125I]insulin to 30-day-old fetal heart membranes from a control of 3.6 ± 0.74% per 100 μg protein to 5.8 ± 0.19% (p < 0.05). Curvilinear Scatchard plots revealed an increase in receptor number × 107 μg protein-1 from 137 ± 4 to 244 ± 39 (p < 0.05) with no change in receptor affinity. No appreciable alteration by T4 in the [125I]insulin-specific binding and receptor number of 30-day fetal brains was noted. Fetal heart glycogen content was decreased and there was a small increase in plasma glucose concentration in the T4-treated group (each p < 0.02). Betamethasone at 0.17 mg/kg did not affect the specific binding of [125I]insulin to 27-day fetal heart or brain plasma membranes, although a decrease in heart glycogen content and an increase in plasma glucose concentration were observed (each p < 0.02). Also T4 + betamethasone did not alter the [125I]insulin binding to 27-day fetal heart or brain plasma membranes, but resulted in an additive effect (a marked depletion) on cardiac glycogen (p < 0.001). Brain glycogen was undetectable in all fetuses, control of treated (regardless of the type of hormonal treatment). Thus T4 and glucocottcoids produce different effects on developing fetal brain and heart insulin receptors, alon with a depletion of the myocardial glycogen stores.
糖皮质激素和甲状腺功能减退症调节胎儿肺胰岛素受体的发育。
DOI：
10.1152/ajpendo.1982.242.6.e384
发表时间：
1982
期刊：
The American journal of physiology
影响因子：
--
作者：
Devaskar,SU;Ganguli,S;Devaskar,UP;Sperling,MA
通讯作者：
Sperling,MA
改变自发性糖尿病大鼠心肌糖原代谢的调节。
DOI：
10.1152/ajpendo.1983.245.4.e379
发表时间：
1983
期刊：
The American journal of physiology
影响因子：
--
作者：
MillerJr,TB
通讯作者：
MillerJr,TB
新生犬肾上腺素能反应受损的细胞机制。
DOI：
10.1172/jci110038
发表时间：
1981
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
Rockson,SG;Homcy,CJ;Quinn,P;Manders,WT;Haber,E;Vatner,SF
通讯作者：
Vatner,SF