Navigation Links
Cause of Gender Differences in Blood Pressure, Kidney Damage Under Study

While men and women both get high blood pressure and related kidney disease, the path to get there is shorter, steeper and just different for men , researchers say.

They may end up at the same point, but the way they got there could be very different, says Dr. Jennifer C. Sullivan, pharmacologist/physiologist at the Medical College of Georgia Vascular Biology Center.

Its known that men tend to develop hypertension earlier than women and the increase in blood pressure occurs more rapidly than it does in women, until they hit menopause. I look at our spontaneously hypertensive rats and see the same dichotomy in blood pressure, Dr. Sullivan says of the animal model she studies. There are also differences in development of renal injury in the human population and chronic renal disease seems to be worse in men and I see the same thing in my animal model.

Shes looking at these gender differences to find what protects females, at least for much of their life, work that led to her selection for the 2007 New Investigator Award of the American Physiological Societys Water and Electrolyte Homeostasis Section. She presented her work May 1 during the Experimental Biology Meeting Annual Meeting in Washington, D.C.

Female hormones cant account for all the difference, she says. Its not that easy. Men and women are more than just sex hormones. When she takes testicles out, for example, blood pressure and injury incidence drop some; when she takes ovaries out, blood pressure remains unchanged but kidney injury increases slightly. There are fundamental differences, I believe, in the physiology. They are going to end up at the same point but the way there could be very different.

So shes comparing in males and females some major players in blood pressure regulation and renal injury: the potential for blood vessels to relax and constrict and the amount of damage-producing free radicals.

Shes finding that nitric oxide synthase, which makes nitric oxide, a signaling molecule that tells smooth muscles cells to relax, may make more nitric oxide in females. Just how active an enzyme is depends on how its phosphorylized, or turned on by adding phosphate groups. Our preliminary data says that the phosphorylation status may increase nitric oxide production - and maintain kidney health - in females, Dr. Sullivan says.

In contrast is the powerful constrictor of blood vessels, angiotensin 2. In the outer most part of their kidneys, males have a lot of the AT1 receptors that enables angiotensin 2 to do harm. Its a vasoconstrictor when it binds with AT1, she says. It will cause proliferation, it will cause hypertrophy, it can stimulate the production of reactive oxygen species, so it does all sorts of bad things, she says.

Fortunately there are already drugs that block angiotensin 2s destructive action: angiotensin receptor blockers and ace inhibitors. Interestingly, clinical studies already have shown these drugs dont work as well in women. A lot of women are on these drugs too and Im not sure its doing them a lot of good, she says. One of her goals is to find out.

When she looks in the outer most part of the kidney, called the renal cortex, she also finds males have too many highly reactive and potentially damaging free radicals. Free radicals or reactive oxygen species have important jobs in the body, like cell signaling, but as with anything, its all about balance.

When there are too many, it creates oxidative stress, a contributor to most major diseases, such as cancer and cardiovascular disease, as well as aging in general. In high blood pressure, free radicals damage proteins critical to blood vessels and the kidneys.

The body has natural mechanisms for keeping free radicals in check, including endogenous antioxidants. But if you get increases, it ca n overwhelm the natural ability of the body to take care of it, she says.

When she looks to see the toll all this takes on the kidneys, she finds about a 50 percent increase in the amount of protein excreted in the urine - a sure sign of kidney disease - in the males.

She notes that by age 70, the rates of cardiovascular disease and hypertension are similar in men and women and that older women tend to have higher blood pressures than age-matched men.

Dr. Sullivan earned her Ph.D. at Albany Medical College in New York before becoming a postdoctoral fellow at MCG in 2000 and joining the faculty in 2003. She received the American Physiological Society Research Recognition Award in 2003 and the Merck New Investigator Award in 2006. Her work is funded in part by an American Heart Association Scientist Development Grant.


Related medicine news :

1. Is Diabetes the Leading Cause of Kidney Failure in India
2. Antibiotics Dangerous for Diarrhoea in Children Caused by E.Coli
3. Paracetamol May Cause Live Damage Warns Consumer Education and Research Centre
4. Breast Cancer Surgery Causes Psychological problems
5. Arthritis Drug May Cause Liver Damage
6. Causes of weakness in the aged
7. Gene Mutation Causes Ovarian Failure
8. Does Radiation Cause Lung Cancer?
9. Chronic Diseases said to Cause Falls in the Elderly
10. Vision Loss Due To Diabetic Retinopathy a Major Cause Of Concern
11. Low Testosterone Levels the Cause Of Depression In Men
Post Your Comments:

(Date:6/27/2016)... ... June 27, 2016 , ... ... today announced its strategic partnership with Connance, a healthcare industry leader providing ... companies’ proven, proprietary technology combine to provide health systems, hospitals and ambulatory ...
(Date:6/27/2016)... Park, KS (PRWEB) , ... June 27, 2016 , ... ... in retailers of Eyeglasses . , Millions of individuals in the United States ... eyeglasses have become a way to both correct vision and make a fashion statement. ...
(Date:6/26/2016)... Creek, Michigan (PRWEB) , ... June 26, 2016 , ... ... joined as sponsor of the 2016 Cereal Festival and World’s Longest Breakfast Table in ... in honor of the city’s history as home to some of the world’s leading ...
(Date:6/26/2016)... ... 26, 2016 , ... PawPaws brand pet supplements owned by Whole ... enhance the health of felines. The formula is all-natural and is made from Chinese ... PawPaws Cat Kidney Support Supplement Soft Chews are Astragalus Root Extract and ...
(Date:6/26/2016)... ... June 26, 2016 , ... Many women are confused ... endometriosis. These women need a treatment plan to not only alleviate symptoms and ... help for preservation of fertility and ultimately achieving a pregnancy. The specialists at ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... DUBLIN , June 24, 2016 ... and Markets has announced the addition of the ... their offering. ... products and provides an updated review, including its applications ... covering the total market, which includes three main industries: ...
(Date:6/24/2016)... 24, 2016 Research and Markets has ... Companion Diagnostic Tests" report to their offering. ... Diagnostics The World Market for Companion Diagnostics ... diagnostics. Market analysis in the report includes the following: ... Vitro Diagnostic Kits) by Region (N. America, EU, ROW), 2015-2020 ...
(Date:6/23/2016)... 23, 2016  MedSource announced today that it ... software solution of choice.  This latest decision demonstrates ... to their clients by offering a state-of-the-art electronic ... establishes nowEDC as the EDC platform of choice ... clients.  "nowEDC has long been a preferred EDC ...
Breaking Medicine Technology: