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:
*Name:
*Comment:
*Email:


(Date:6/24/2016)... ... June 24, 2016 , ... Marcy was in a crisis. Her son James, eight, was out ... family verbally and physically. , “When something upset him, he couldn’t control his emotions,” remembers ... would throw rocks at my other children and say he was going to kill them. ...
(Date:6/24/2016)... ... June 24, 2016 , ... ... micro-osteoperforation for accelerated orthodontic treatment. Dr. Cheng has extensive experience with all areas ... , AcceleDent, and accelerated osteogenic orthodontics. , Micro-osteoperforation is a revolutionary adjunct ...
(Date:6/24/2016)... ... 2016 , ... People across the U.S. are sharpening their pencils and honing ... contest in which patients and their families pay tribute to a genetic counselor by ... Society of Genetic Counselors (NSGC) Annual Education Conference (AEC) this September. , In ...
(Date:6/24/2016)... ... June 24, 2016 , ... Puradigm® & Innovative Solutions ... initiated cultivation and processing operations at its production facility, and opened its first ... is the manufacturer of a complete system of proactive air and surface purification ...
(Date:6/24/2016)... ... 2016 , ... Venture Construction Group (VCG) sponsors Luke’s Wings ... at the Woodmont Country Club at 1201 Rockville Pike, Rockville, Maryland, 20852. The ... members that have been wounded in battle and their families. Venture Construction Group is ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... 2016 Research and Markets has announced ... Analysis 2016 - Forecast to 2022" report to their ... contains up to date financial data derived from varied research ... trends with potential impact on the market during the next ... which comprises of sub markets, regional and country level analysis. ...
(Date:6/23/2016)... and INDIANAPOLIS , June 23, ... a Lilly Diabetes Tomorrow,s Leaders Scholarship is any indication, ... winners, announced today online at www.diabetesscholars.org by ... 1 diabetes stand in the way of academic and ... the Foundation,s scholarship program since 2012, and continues to ...
(Date:6/23/2016)... Research and Markets has announced the addition ... States, China, Japan, Brazil, United Kingdom, Germany, France, Italy, ... Surgical Procedure Volumes: Global ... surgical procedure volume data in a geographic context. The ... of growth drivers and inhibitors, including world population growth, ...
Breaking Medicine Technology: