Chronic exposures to low levels of estradiol and their effects on the ovaries and reproductive hormones: Comparison with aging

Endocrine Disruptors
E T GilbreathP S Mohankumar

Abstract

Aging in female rats is characterized by a state called "constant estrous" in which rats are unable to ovulate, have polycystic ovaries and moderately elevated estrogen levels. We hypothesized that chronic exposure of young animals to low levels of E2 can produce reproductive changes similar to that seen in aging animals. Adult female rats were sham-implanted (control) or implanted with slow-release E2 (20 ng/day) pellets for 30, 60, or 90 days. Old constant estrous (OCE) rats were used for comparison. Estrous cyclicity was monitored periodically. At the end of treatment, animals were sacrificed, trunk blood was collected for hormone measurements and ovaries for immunohistochemistry. Young animals became acyclic with increasing duration of E2 exposure while OCE rats were in a state of acyclicity. Ovaries became increasingly more cystic with E2 exposure, and were comparable to OCE rats; however, there was a marked reduction in interstitial tissue with exogenous E2 treatment. Exogenous E2 also decreased Mullerian inhibiting substance expression, increased infiltration of macrophages without much impact on apoptosis in the ovaries. Serum testosterone levels decreased in E2-treated young animals, while it increased significantly in...Continue Reading

References

Jan 1, 1979·Advances in Experimental Medicine and Biology·L G Paavola
Jul 1, 1977·Endocrinology·C S CampbellM G Firlit
Jul 1, 1977·Journal of Gerontology·S W Chan, J H Leathem
Aug 1, 1979·Experimental Aging Research·J J PelusoJ Meites
Jan 1, 1982·Experimental Aging Research·R W Steger, J J Peluso
May 1, 1993·Biology of Reproduction·L M Quandt, R J Hutz
Aug 1, 1995·Human Reproduction·A H BalenH S Jacobs
Nov 6, 2002·Reproduction : the Official Journal of the Society for the Study of Fertility·Alexandra L L DurlingerAxel P N Themmen
Dec 10, 2003·Obstetrics and Gynecology·Kate M Brett, Cynthia A Reuben
Apr 10, 2004·Human Reproduction Update·Ruijin WuRebecca L Robker
May 7, 2004·Reproduction : the Official Journal of the Society for the Study of Fertility·M MyersJ B Kerr
Jan 3, 2006·Reproduction : the Official Journal of the Society for the Study of Fertility·Jenny A VisserAxel P N Themmen
Aug 31, 2006·Reproduction : the Official Journal of the Society for the Study of Fertility·Deepak ModiChander Puri
Feb 26, 2009·Cancer Epidemiology, Biomarkers & Prevention : a Publication of the American Association for Cancer Research, Cosponsored by the American Society of Preventive Oncology·Kathleen A O'ConnorMaxine Weinstein
May 20, 2009·Reproductive Biology and Endocrinology : RB&E·John C ChapmanSandra D Michael
Jun 3, 2009·The American Journal of Medicine·Abby L SpencerMegan C McNamara
Apr 22, 2011·The New England Journal of Medicine·Annekathryn GoodmanMichael F Greene
Jun 2, 2012·Frontiers in Endocrinology·Sally RadovickAndrew Wolfe

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Citations

Mar 17, 2018·Gynecological Endocrinology : the Official Journal of the International Society of Gynecological Endocrinology·Yang YeShu-Ming Huang

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Methods Mentioned

BETA
light microscopy

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NIS

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Apoptosis

Apoptosis is a specific process that leads to programmed cell death through the activation of an evolutionary conserved intracellular pathway leading to pathognomic cellular changes distinct from cellular necrosis