Featured Research

from universities, journals, and other organizations

Drug Lowers Body's 'Set Point' To Control Hyperparathyroidism In Dialysis Patients

Date:
July 16, 2008
Source:
American Society of Nephrology
Summary:
A medication called cinacalcet -- an important part of treatment to control high levels of parathyroid hormone in patients receiving dialysis for end-stage renal disease -- works by resetting the balance between calcium and PTH levels, according to a new study.

A medication called cinacalcet--an important part of treatment to control high levels of parathyroid hormone (PTH) in patients receiving dialysis for end-stage renal disease (ESRD)--works by resetting the balance between calcium and PTH levels, according to a new study.

Cinacalcet is one of a family of drugs called calcimimetics. "In hemodialysis patients, the use of calcimimetics decreases the set point of the PTH-calcium curve, which means that PTH secretion by cells is suppressed at low or normal calcium levels," comments Mariano Rodriguez, MD, PhD, of Nephrology Service, Hospital Universitario Reina Sofia in Cordoba, Spain.

Dr. Rodriguez and colleagues studied responses to cinacalcet treatment in nine patients with ESRD receiving long-term hemodialysis to replace lost kidney function. All patients had high levels of PTH, or secondary hyperparathyroidism--a frequent complication of kidney disease that is mainly caused by low calcium levels. Hyperparathyroidism can lead to weakening of the bones and other problems, including cardiovascular disease.

The researchers assessed the "PTH-calcium curve," which reflects the way PTH levels respond to calcium levels, by comparing blood samples obtained during dialysis performed at low and high calcium levels. The study took advantage of a new test that provides more complete information on the dynamics of PTH secretion.

Treatment with cinacalcet led to significant reductions in the patients' blood phosphorus levels. Their levels of PTH before dialysis were also decreased.

Cinacalcet also led to a reduction in the set point of the PTH-calcium curve. This occurred because cinacalcet made parathyroid cells more sensitive to calcium.

The study provides important new information on how cinacalcet and other calcimimetic drugs work to reduce PTH levels. Normally, low calcium levels cause cells to increase secretion of PTH. After cinacalcet treatment, PTH secretion doesn't increase even when calcium levels are low. Cinacalcet doesn't just lower calcium and PTH levels in the short term, the new results suggest--it changes the interaction between calcium and PTH levels in the long term.

Secondary hyperparathyroidism is a common and potentially serious problem in patients with kidney disease. Calcimimetic drugs like cinacalcet provide a valuable new treatment option. "Nowadays the calcimimetics are an essential tool in the treatment of secondary hyperparathyroidism," says Dr. Rodriguez. "With these drugs, the need for surgery to remove the parathyroid gland (parathyroidectomy) is markedly decreased."

The results provide nephrologists with new insights into the way cinacalcet works to control PTH levels in ESRD patients with hyperparathyroidism. "High PTH levels and the excess of calcium in blood are easy to control with calcimimetics," Dr. Rodriguez adds.

The study was limited by the lack of data on the effects of cinacalcet in patients on peritoneal dialysis, although there are no reasons to believe that results would have been different in peritoneal dialyisis patients. In addition, the patients in the study were not taking vitamin D, another effective treatment for hyperparathyroidism. "It would have been interesting to evaluate the combined effect of calcimimetics and vitamin D on the set point of the PTH-calcium curve," says Dr. Rodriguez.

Funding was provided by Government grants from instituto Carlos III, Consejeria de Salud de la Junta de Andalucia and Fundaciσn Nefrologica and Red de Investigaciσn Renal. Funding for the writing was provided by Amgen Europe.

 


Story Source:

The above story is based on materials provided by American Society of Nephrology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Cinacalcet Reduces the Set Point of the Parathyroid Hormone -Calcium Curve in Hemodialysis Patients with Secondary Hyperparathyroidism. Journal of the American Society of Nephrology, (online July 16, 2008) Print edition November 2008

Cite This Page:

American Society of Nephrology. "Drug Lowers Body's 'Set Point' To Control Hyperparathyroidism In Dialysis Patients." ScienceDaily. ScienceDaily, 16 July 2008. <www.sciencedaily.com/releases/2008/07/080716171136.htm>.
American Society of Nephrology. (2008, July 16). Drug Lowers Body's 'Set Point' To Control Hyperparathyroidism In Dialysis Patients. ScienceDaily. Retrieved April 25, 2014 from www.sciencedaily.com/releases/2008/07/080716171136.htm
American Society of Nephrology. "Drug Lowers Body's 'Set Point' To Control Hyperparathyroidism In Dialysis Patients." ScienceDaily. www.sciencedaily.com/releases/2008/07/080716171136.htm (accessed April 25, 2014).

Share This



More Health & Medicine News

Friday, April 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) — A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
Companies Ramp Up Wellness to Lower Health Costs

Companies Ramp Up Wellness to Lower Health Costs

AP (Apr. 24, 2014) — That little voice telling you to exercise, get in shape and get healthy is probably coming from your boss. More companies are beefing up wellness programs to try and cut down their health care costs. (April 24) Video provided by AP
Powered by NewsLook.com
Blood From World's Oldest Woman Suggests Life Limit

Blood From World's Oldest Woman Suggests Life Limit

Newsy (Apr. 24, 2014) — Scientists say for the extremely elderly, their stem cells might reach a state of exhaustion. This could limit one's life span. Video provided by Newsy
Powered by NewsLook.com
FDA Wants To Ban Sales Of E-Cigarettes To Minors

FDA Wants To Ban Sales Of E-Cigarettes To Minors

Newsy (Apr. 24, 2014) — The Food and Drug Administration wants to crack down on the use of e-cigarettes, banning the sale of the product to minors. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins