Somatomedin C: Restoration in Vivo of Cycle Traverse in G ₀ /G ₁ Blocked Cells of Hypophysectomized Animals

Abstract

DNA synthesis and mitosis in frog lens epithelium are abolished by hypophysectomy and restored by somatomedin C. Both growth hormone and triiodothyronine also restore lens cell proliferation in vivo but not in vitro. Somatomedin-like activity in frog serum is diminished by hypophysectomy and is restored by growth hormone and triiodothyronine.