Effect of thyroid hormones, somatotrophin, insulin and corticosteroids on synthesis of collagen in granulation tissue both in vivo and in vitro.

Abstract

ABSTRACT The effect of hormonal factors on the collagen synthesis in experimental granulation tissue of rats was studied (1) in vivo by assessing the development of the tensile strength and (2) in vitro by measuring the capacity of collagen synthesis from 14C-proline by incubated granuloma slices. The hormonal agents were either administered in vivo or added to the incubation media. When hormones were given in vivo, only cortisol affected the tensile strength of the granuloma markedly, but when the capacity of collagen synthesis was assessed, it was found that somatotrophin slightly increased and thyroxine decreased the synthesis. The effect of glucocorticoids, if any, was to increase the conversion of labelled proline into hydroxyproline. In those experiments in which the hormonal factors were added to the incubation media, thyroxine and particularly insulin, increased the incorporation of 14C-proline into collagen. Somatotrophin decreased the incorporation of proline in these experiments, presumably by artifact reactions.