Endocrine regulation of fetal adipose tissue metabolism in the pig: Interaction of porcine growth hormone and thyroxine
Endocrine regulation of fetal adipose tissue metabolism in the pig: Interaction of porcine growth hormone and thyroxine
复制标题
DOI：
10.1002/j.1550-8528.1999.tb00393.x
复制
发表时间：
1999-01-01
期刊：
影响因子：
--
通讯作者：
Martin, RJ
中科院分区：
文献类型：
--
作者：
Hausman, DB;Hausman, GJ;Martin, RJ
目的：本研究测试了甲状腺素（T-4）和生长激素（GH）联合治疗可以使垂体切除胎猪脂肪组织发育的细胞和代谢正常化的假设。研究方法和程序：在妊娠第 70 天，通过微烧灼法切除猪胎儿的垂体或保持完整。垂体切除术的胎儿未接受治疗，或在妊娠第 90 天至 105 天期间接受 T-4、GH 或两种激素的组合治疗。结果：体重不受垂体切除术或激素治疗的影响。通过垂体切除术，皮下脂肪组织的从头脂肪生成增加了 10 倍，这与我们之前的结果一致。这种增加通过垂体切除胎儿的 GH 治疗消除。相比之下，T-4 治疗垂体切除的胎儿导致脂肪组织脂肪生成进一步增加 12 倍，但同时施用 GH 可以抵消这一效应。垂体切除术降低了对异丙肾上腺素的脂解反应，不受 GH 治疗的影响，并且在垂体切除的胎儿中通过 T-4 或 T-4+GH 治疗恢复到完整值。 讨论：与 T-4 相比，GH 不影响血清胰岛素样生长因子-I 或脂肪组织脂解作用，但会减少胎猪的脂肪生成。然而，与单独使用 GH 或 T-4 相比，同时替换 T-4 和 GH 可以更大程度地使垂体切除胎儿正常化。因此，甲状腺激素对刺激发育中的胎猪脂肪组织脂肪生成的任何影响通常可以通过垂体衍生的生长激素来抵消。
Objective: This study tested the hypothesis that combined treatment of thyroxine (T-4) and growth hormone (GH) could normalize cellular and metabolic aspects of adipose tissue development of hypophysectomized fetal pigs.Research Methods and Procedures: On day 70 of gestation, pig fetuses were hypophysectomized by microcauterization or remained intact. Hypophysectomized fetuses remained untreated or were treated from day 90 to day 105 of gestation with T-4, GH, or a combination of both hormones.Results: Body weights were unaffected by hypophysectomy or hormone treatment. De novo lipogenesis in subcutaneous adipose tissue was increased 10-fold by hypophysectomy, consistent with our previous results. This increase was abolished by GH treatment in the hypophysectomized fetuses. In contrast, T-4 treatment of the hypophysectomized fetuses resulted in a 12-fold further increase in adipose tissue lipogenesis, an effect that was negated by concomitant administration of GH. Lipolytic response to isoproterenol was decreased by hypophysectomy, unaffected by GH treatment, and restored to intact values by T-4 or by T-4+GH treatment in the hypophysectomized fetuses.Discussion: In contrast to T-4, GH does not influence serum insulin-like growth factor-I or adipose tissue lipolysis, but decreases lipogenesis in the fetal pig. However, replacing both T-4 and GH normalized hypophysectomized fetuses to a greater extent than either GH or T-4 alone. Thus, any influence of thyroid hormones on stimulating adipose tissue lipogenesis in the developing fetal pig may be normally counterregulated by pituitary-derived growth hormone.