AJP - Gastrointestinal and Liver Physiology, Vol 262, Issue 1 185-G190, Copyright © 1992 by American Physiological Society
Leuprolide acetate affects intestinal motility in female rats before and after ovariectomy
R. Khanna, R. M. Browne, A. D. Heiner, M. H. Clench and J. R. Mathias
Department of Internal Medicine, School of Medicine, University of Texas Medical Branch, Galveston 77550.
Leuprolide acetate, a gonadotropin-releasing hormone (GnRH) analogue, is
currently being proposed to control debilitating symptoms in women with
functional bowel disease. Whether leuprolide alters gastrointestinal
motility as part of its actions is unknown. This study was designed to
assess, using myoelectric techniques in an animal model, the effects of
leuprolide on potential mechanisms of neuromuscular function of small
intestine. Female rats with (n = 6) or without (n = 8) bilateral
ovariectomy were used to study jejunal motility before and after leuprolide
therapy. Throughout the study, daily leuprolide dosages of 0.02, 0.2, or
0.4 micrograms/kg were injected into intact rats and 0.02, 0.2, 0.4, 1.0,
or 2.5 micrograms/kg into ovariectomized rats. Recordings were made while
the rats were fasted and postprandial and before and after leuprolide
administration. Under control conditions, migrating myoelectric complexes
(MMCs) were found in intact female rats, whether fasted or postprandial.
After ovariectomy, postprandial controls and those treated with low-dose
leuprolide (0.02, 0.2, and 0.4 micrograms) had typical fed-state patterns
and no MMCs, but at 1.0 and 2.5 micrograms the fed state was inhibited and
cycling MMCs occurred at a frequency similar to that of fasted controls.
Reproductive hormones thus have a significant effect on gastrointestinal
motility.
