Effects [jy1]of estrogen and growth hormone on skeleton in the
ovariectomized rat with hypophysectomy..
Yeh, James K., Meng-Meng Chen, and John F. Aloia.
Department of Medicine, Winthrop-University Hospital, Mineola, NY,
The Health Sciences Center, State University of New York at Stony
Brook. NY
APStracts 4:0140E, 1997.
To investigate whether growth hormone (GH) and 17(-estradiol (E2)
replacement can prevent osteopenia induced by pituitary and ovarian
hormone deficiency (HX+OV), we administered relatively low dosages of
GH (2.3 IU/kg/d) and E2 (100 ug/kg/wk) in experiment one and
relatively high dosages of GH (13.5 IU/kg/d) and E2 (3500 ug/kg/wk)
in experiment two to 2 month old HX+OV Sprague-Dawley rats for 6
weeks. Our data shows that the HX+OV of rats results in diminished
periosteal bone formation, longitudinal bone growth and decreased
cancellous bone volume. Administration of either the low or high
dosage of GH to these rats increased their systemic growth, serum
levels of osteocalcin, and cortical bone formation. Either low or
high dosages of GH or E2 alone only partially prevent cancellous bone
loss. However, the combined treatment of GH + E2 resulted in an
additive increase in the cancellous bone mass. We conclude that the
additive effect of GH + E2 on cancellous bone is attributed to the
suppressive effect of E2 on bone resorption, and the anabolic effect
of GH on bone formation.
Received 6 December 1996; accepted in final form 20 June 1997.
APS Manuscript Number E620-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 10 July 1997