Endocrinology, Vol 130, 805-810, Copyright © 1992 by Endocrine Society

ARTICLES

Differential contributions of ovarian and extraovarian factors to age- related reductions in plasma estradiol and progesterone during the estrous cycle of C57BL/6J mice

JF Nelson, LS Felicio, HH Osterburg and CE Finch
Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada.

The relative contributions of ovarian and extra-ovarian factors to the altered ovarian steroidal profiles of middle-aged mice were assessed by reciprocal, heterochronic ovarian grafting. Ovaries from cycling, young (2 months), and middle-aged (12 months) mice were exchanged by grafting under the renal capsules. Blood samples were obtained daily at midday throughout the estrous cycle for measurement of estradiol (E2) and 3-4 h after lights-out on proestrus to measure the preovulatory elevation of progesterone (P4). Middle-aged intact mice had lower mean concentrations of E2 during the cycle, no detectable midday preovulatory elevation of E2, and an attenuated preovulatory increase of P4 compared to young mice. Ovarian grafts from young donors failed to increase mean E2 levels of middle-aged mice, but did restore the preovulatory elevation of E2 and preovulatory P4 to levels of young controls. Reciprocal grafting confirmed these findings: ovaries from middle-aged donors in young hosts produced mean E2 levels equivalent to those of young mice but were unable to support a preovulatory increase of E2 or a preovulatory P4 level equivalent to that of young controls. These results reveal differential contributions of ovarian and extra- ovarian factors to age changes in E2 and P4. They indicate that ovarian aging plays an important role in attenuating the preovulatory increase of E2 and P4, but extra-ovarian, presumably neuroendocrine, age changes underlie the mean reduction of E2 levels across the estrous cycle.

This article has been cited by other articles:

				M. Almeida, L. Han, M. Martin-Millan, L. I. Plotkin, S. A. Stewart, P. K. Roberson, S. Kousteni, C. A. O'Brien, T. Bellido, A. M. Parfitt, et al. Skeletal Involution by Age-associated Oxidative Stress and Its Acceleration by Loss of Sex Steroids J. Biol. Chem., September 14, 2007; 282(37): 27285 - 27297. [Abstract] [Full Text] [PDF]

				L. Wang, Y.-D. Wang, W.-J. Wang, Y. Zhu, and D.-J. Li Dehydroepiandrosterone improves murine osteoblast growth and bone tissue morphometry via mitogen-activated protein kinase signaling pathway independent of either androgen receptor or estrogen receptor J. Mol. Endocrinol., April 1, 2007; 38(4): 467 - 479. [Abstract] [Full Text] [PDF]

				J J Whyte, A P Alexenko, A M Davis, M R Ellersieck, E D Fountain, and C S Rosenfeld Maternal diet composition alters serum steroid and free fatty acid concentrations and vaginal pH in mice J. Endocrinol., January 1, 2007; 192(1): 75 - 81. [Abstract] [Full Text] [PDF]

				D. B. Dubal, S. W. Rau, P. J. Shughrue, H. Zhu, J. Yu, A. B. Cashion, S. Suzuki, L. M. Gerhold, M. B. Bottner, S. B. Dubal, et al. Differential Modulation of Estrogen Receptors (ERs) in Ischemic Brain Injury: A Role for ER{alpha} in Estradiol-Mediated Protection against Delayed Cell Death Endocrinology, June 1, 2006; 147(6): 3076 - 3084. [Abstract] [Full Text] [PDF]

				C. A. Christian, J. L. Mobley, and S. M. Moenter Diurnal and estradiol-dependent changes in gonadotropin-releasing hormone neuron firing activity PNAS, October 25, 2005; 102(43): 15682 - 15687. [Abstract] [Full Text] [PDF]

				S. Sedej, T. Tsujimoto, R. Zorec, and M. Rupnik Voltage-activated Ca2+ channels and their role in the endocrine function of the pituitary gland in newborn and adult mice J. Physiol., March 15, 2004; 555(3): 769 - 782. [Abstract] [Full Text] [PDF]

				C. S. Nunemaker, M. Straume, R. A. DeFazio, and S. M. Moenter Gonadotropin-Releasing Hormone Neurons Generate Interacting Rhythms in Multiple Time Domains Endocrinology, March 1, 2003; 144(3): 823 - 831. [Abstract] [Full Text] [PDF]

				R. A. DeFazio and S. M. Moenter Estradiol Feedback Alters Potassium Currents and Firing Properties of Gonadotropin-Releasing Hormone Neurons Mol. Endocrinol., October 1, 2002; 16(10): 2255 - 2265. [Abstract] [Full Text] [PDF]

				E. F. Rissman, A. L. Heck, J. E. Leonard, M. A. Shupnik, and J.-A. Gustafsson Disruption of estrogen receptor beta gene impairs spatial learning in female mice PNAS, March 19, 2002; 99(6): 3996 - 4001. [Abstract] [Full Text] [PDF]

				D. B. Dubal, H. Zhu, J. Yu, S. W. Rau, P. J. Shughrue, I. Merchenthaler, M. S. Kindy, and P. M. Wise Estrogen receptor alpha , not beta , is a critical link in estradiol-mediated protection against brain injury PNAS, February 1, 2001; (2001) 41483198. [Abstract] [Full Text]

				A. C. Gore, G. Yeung, J. H. Morrison, and T. Oung Neuroendocrine Aging in the Female Rat: The Changing Relationship of Hypothalamic Gonadotropin-Releasing Hormone Neurons and N-Methyl-D-Aspartate Receptors Endocrinology, December 1, 2000; 141(12): 4757 - 4767. [Abstract] [Full Text] [PDF]

				D. B. Dubal, H. Zhu, J. Yu, S. W. Rau, P. J. Shughrue, I. Merchenthaler, M. S. Kindy, and P. M. Wise Estrogen receptor alpha , not beta , is a critical link in estradiol-mediated protection against brain injury PNAS, February 13, 2001; 98(4): 1952 - 1957. [Abstract] [Full Text] [PDF]