Study sheds more light on the role of estrogen and cardiac remodeling.

2002 NOV 14 - (NewsRx.com & NewsRx.net) -- by Sonia Nichols, senior medical writer - Estrogen deprivation appears to hamper coronary vascular remodeling in middle-aged female rats, according to a Japanese study.

Recently, the authors of a major long-term study of hormone replacement therapy (HRT) in menopausal women advised against prescribing it for heart disease prevention, warning that its risks may outweigh its benefits. Those women were taking a combination of estrogen and progestin, and they had not undergone hysterectomies.

Now though, investigators at Hokkaido University School of Medicine in Sapporo, Japan, have reported that estrogen deficiency may hamper proper capillary remodeling in the hearts of female middle-aged rats, potentially causing them increased risk for cardiac disease. There may a comparable risk for those same effects in postmenopausal women, the researchers suggest.

In the Japanese study, Subrina Jesmin and colleagues induced estrogen deprivation by removing ovaries from several 40-week-old, middle-aged female rats. They treated other same-aged female rats to surgery without ovarian removal. Several of the ovariectomized rats received estrogen replacement therapy (ERT).

Female rats with removed ovaries showed evidence of reduced coronary capillary density, but ERT reversed those effects, according to Jesmin and coauthors (In vivo estrogen manipulations on coronary capillary network and angiogenic molecule expression in middle-aged female rats. Arteriosclerosis, Thrombosis, and Vascular Biology, 2002;22(10):1591-1597).

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