November 25, 2001 -- Bethesda, Md. The American Journal of Physiology: Endocrinology and Metabolism, one of the 14 peer-reviewed journals published by the American Physiological Society (APS), spotlights recent research findings designed to improve and understand human well-being and health. The December edition includes a twin pair of crossover studies that find oral administration of estrogen replacement therapy (ERT) suppresses the biological actions of the growth hormone in women with key hormonal deficiencies.
Growth hormones have recently been approved for replacement treatment in adults in several countries. They play an important role in regulating body composition and physical and psychological well-being in adult life. However, there is limited information regarding the interaction of growth hormones with other hormones during replacement therapy. Accordingly, observations in postmenopausal women raised the question as to whether the traditional oral route of estrogen replacement reduces the biological effects of growth hormones.
Two studies were undertaken comparing the effects of oral and transdermal estrogen administration on the biological actions of growth hormones. Doses employed are those routinely used in the therapy of women with hypopituitarism. The first study investigated insulin-like growth factor I (IGF-I) responses to three different doses of GH (dose-response study). The second study investigated metabolic effects of growth hormone GH on lipid oxidation and whole body protein metabolism (metabolic study).
The authors of the studies, Oral Estrogen Antagonizes the Metabolic Actions of Growth Hormone In Growth Hormone-Deficient Women, are Troels Wolthers, David M. Hoffman, Ailish G. Nugent, an
Contact: Donna Krupa
American Physiological Society