Effects of thyroxin injections on growth and differentiation of the skeleton of hypophysectomized female rats

✍ Scribed by Ray, Robert D. ;Asling, C. Willet ;Simpson, Miriam E. ;Evans, Herbert M.

• Publisher: John Wiley and Sons
• Year: 1950
• Tongue: English
• Weight: 585 KB
• Volume: 107
• Category: Article
• ISSN: 0003-276X
• DOI: 10.1002/ar.1091070305

✦ Synopsis

SEVEN FIGURES

The purepose of tliis espcii*iiiiciit was to slutly the effects of tliyroxiii iiijectioiih 011 skclctal growth ztiid diffcreiitiatioii in Iiypoy~hysectoniized rat s.

A s noted ill a pi-evions paper (liay, Simpson, Li, dsliiig mid Evaiis, '50) tlie results of' cspcrirneiits concluctecl at tlw Iiistitute of Ehperiirieii tal Biology (Evans, S i n i p o n aiid Peiicharz, '39; Becks, Ray, Kinipson aiid Evans, '42) and those conducted by Lacpeur, Dingemaiise and Freud ( '41) h a i ~ heeii at variance. The Amsterdam gi*oup have reported that they were able to obtain growth in hypophyscctomized rats with "thyranon pro injectione" (N. V. Organon in Oss), a protcolytic degradation product of thyroid gland. This snbstaiice was injected at n daily dose of 2.5 to 5 p g of organic l~ouiid iodine. Tlic exact tliyroxin equivaleiit of this dosage cannot be computed. The increase of weight of 8 hypophpsectoiiiizcd male rats dnriiig three weeks of ii-,jections averaged 16 gin. Repeated experiments by tlie Berkeley group, on the other hand, have failed to confirm this finding. The cssential difference between the experiments conducted by the two groups may have been the dose level of thyroid hor-(C2) alld t h e Researcli Board of tlic University of California. * Aided by gmnts f i o i n the Uiiitcd States Pnblic Health Service Grant XG-409 253