| Abstract: | Fifteen sheep fetuses hypophysectomized around 115 days gestation (term 150 days) were treated with growth hormone (GH), adrenocorticotrophin (ACTH) or triiodothyronine (T3) by continuous intravenous infusion. At normal or caesarian delivery, about 149 days gestation, body weights and dissectible internal brown fat and subcutaneous white fat depots were compared with seven control hypophysectomized fetuses and four sham-operated controls, the latter groups receiving no hormone infusions. Hypophysectomy caused the appearance of a large persistent depot of subcutaneous fat which was unaffected by ACTH or T3 infusion. Treatment with ovine pituitary GH resulted in the disappearance of this depot which was also absent from the sham-operated controls. Although the GH source was not subjected to extensive purification, there was very little contamination with prolactin or TSH, suggesting that GH itself has a major role in the control of lipid metabolism in the fetus. |
