Selected estrogen compounds modify risks of vein clotting, a response to hormone replacemen...( lled endothelium and smooth muscle whic...)

lled endothelium and smooth muscle which contracts and relaxes resulting in changes in diameter of the veins. These changes in diameter are regulated by chemicals released from the endothelium and the direct action of other chemicals on the smooth muscle. Platelets are fragments of cells in the blood, which participate in formation blood clots. When activated, platelets release chemicals, which also stimulate the endothelium and smooth muscle. Platelets, endothelium and smooth muscle contain receptors that are stimulated by different estrogen-related compounds. But it is not known how stimulation of these receptors by different compounds changes the functions of veins. Experiments were designed to answer this question.

Study
Adult female pigs had their ovaries removed and then were either untreated or treated with either Premarin or raloxifene for four weeks. At this time the femoral veins were removed for study. Hormone Replacement and Function of Veins" is the subject of a study recently conducted by Murat Avsar, Ph.D., and Virginia Miller, Ph.D., both from the Mayo Clinic, Rochester, Mn. Their findings, are being presented at the American Physiological Society (APS) conference, Genomes and Hormones: An Integrative Approach to Gender Differences in Physiology, sponsored by October 17-20, 2001, at the Westin Convention Center, Pittsburgh, Pa.

Results
Both types of hormone replacement modified responses of veins. However, the way the responses of veins were modified was different for the Premarin and raloxifene treated animals. For example, veins from raloxifene-treated pigs contracted more than veins from pigs treated with Premarin. In addition, relaxations to substances released from platelets had a greater affect on the smooth muscle from veins of raloxifene treated pigs. Production of contractile factors from the endothelium were also modified differently by the treatments with more endothelium-derived contractile factor
'"/>

Contact: Donna Krupa
krupaco1@aol.com
703-967-2751
American Physiological Society
18-Oct-2001

Page: 1 2 3
Related biology news :

1. Life-Saving Dr. Mueller Selected To Get Top Sports Medicine Award
2. OHSU-VAMC study sheds light on estrogens benefit for MS
3. Ovarian cancer sheds tumor suppression with loss of estrogen receptor
4. Animal research suggests plant estrogens in soy do not increase breast cancer risk
5. Tamoxifen stimulates breast cancer growth following alteration of estrogen receptor
6. Soy processing influences estrogen-dependent breast cancer growth in mice
7. Exercise reduces blood estrogens, risk for breast cancer in post menopausal women
8. OHSU team discovers compound that lacks estrogens risks
9. Scientists uncover novel role for estrogen in bone marrow
10. Short-term exposure to estrogen cuts fish fertility
11. Scientists identify molecular link between estrogen receptors and invasive growth in breast cancer