Featured Research

from universities, journals, and other organizations

Honeybee Venom Toxin Used To Develop New Tool For Studying Hypertension

Date:
September 24, 2008
Source:
University of Pennsylvania School of Medicine
Summary:
Researchers have modified a honeybee venom toxin so that it can be used as a tool to study the inner workings of ion channels that control heart rate and the recycling of salt in kidneys.

Researchers have found that the honeybee venom toxin, called tertiapin, or TPN, stops the flow of potassium ions across cell membranes by plugging up the opening of Kir channels on the outside of cells. Kir channels in kidneys are potential new targets for treating hypertension.
Credit: iStockphoto/Nathan McClunie

Researchers at the University of Pennsylvania School of Medicine have modified a honeybee venom toxin so that it can be used as a tool to study the inner workings of ion channels that control heart rate and the recycling of salt in kidneys. In general, ion channels selectively allow the passage of small ions such as sodium, potassium, or calcium into and out of the cell.

Related Articles


The study, published in the Proceedings of the National Academy of Sciences, is from the laboratory of Zhe Lu, M.D, Ph.D., Professor of Physiology and a Howard Hughes Medical Institute Investigator, who looked at the action of a natural bee toxin on inward-rectifier potassium channels, Kir channels for short, to identify new approaches to treat cardiovascular disease.

The honeybee venom toxin, called tertiapin, or TPN, stops the flow of potassium ions across cell membranes by plugging up the opening of Kir channels on the outside of cells. Kir channels in kidneys are potential new targets for treating hypertension. "The clue comes from patients with genetic defects in these channels who lose a lot of sodium because it cannot be effectively reabsorbed and thus have low blood pressure," notes Lu. "An inhibitor specifically against these kidney channels will allow this idea to be tested."

Developing a specific inhibitor for one type of Kir channel has been challenging because the target site is very similar among different types of Kir channels. For example, while TPN inhibits Kir type 1 channels in kidney cells, it also inhibits other types of Kir channels in heart cells. After more than a decade, Lu and his colleagues succeeded in bioengineering a TPN that selectively inhibits Kir channels important for salt recycling in kidneys.

By introducing two mutations into TPN, they engineered a variant, called TPNLQ, which stems the flow of potassium ions in renal Kir type 1 channels at low concentrations, and with a 250-fold sensitivity over six other types of Kir channels.

The development of TPNLQ demonstrates that a highly specific inhibitor of potassium channels can be engineered. TPNLQ can now be used as a tool to prove the concept, in animal studies, that reducing salt reabsorption by plugging up renal Kir type 1 potassium channels is a potential new way to treat hypertension.

Yajamana Ramu and Yanping Xu of Penn conducted this study with Dr. Lu. The research was supported by the National Institutes of General Medical Sciences and the University of Pennsylvania Research Foundation.


Story Source:

The above story is based on materials provided by University of Pennsylvania School of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

University of Pennsylvania School of Medicine. "Honeybee Venom Toxin Used To Develop New Tool For Studying Hypertension." ScienceDaily. ScienceDaily, 24 September 2008. <www.sciencedaily.com/releases/2008/09/080917145511.htm>.
University of Pennsylvania School of Medicine. (2008, September 24). Honeybee Venom Toxin Used To Develop New Tool For Studying Hypertension. ScienceDaily. Retrieved February 28, 2015 from www.sciencedaily.com/releases/2008/09/080917145511.htm
University of Pennsylvania School of Medicine. "Honeybee Venom Toxin Used To Develop New Tool For Studying Hypertension." ScienceDaily. www.sciencedaily.com/releases/2008/09/080917145511.htm (accessed February 28, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Saturday, February 28, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could a $34 Smartphone Device Improve HIV Diagnosis in Africa?

Could a $34 Smartphone Device Improve HIV Diagnosis in Africa?

Reuters - Innovations Video Online (Feb. 27, 2015) A dongle that plugs into a Smartphone mimics a lab-based blood test for HIV and syphilis and can detect the diseases in 15 minutes, say researchers. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Doctor Says Head Transplants Possible Within Two Years

Doctor Says Head Transplants Possible Within Two Years

Buzz60 (Feb. 27, 2015) An Italian doctor is saying he could stick someone&apos;s head onto someone else&apos;s body. Patrick Jones (@Patrick_E_Jones) reports. Video provided by Buzz60
Powered by NewsLook.com
How Your Dentist Could Help Screen You For Diabetes

How Your Dentist Could Help Screen You For Diabetes

Newsy (Feb. 27, 2015) A new study from researchers at New York University suggests dentists could soon use blood samples taken from patients&apos; mouths to test for diabetes. Video provided by Newsy
Powered by NewsLook.com
The Best Tips to Makeover Your Health

The Best Tips to Makeover Your Health

Buzz60 (Feb. 27, 2015) If you&apos;re looking to boost your health this season, there are a few quick and easy steps to prompt you for success. Krystin Goodwin (@Krystingoodwin) has the best tips to give your health a makeover this spring! Video provided by Buzz60
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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