IMAGE:This is Dr. Clint Makino of the Makino Laboratory at Mass. Eye and Ear, Harvard Medical School. view more

Credit: Mass. Eye and Ear

Bicarbonate (baking soda) makes sparkling water sparkle, causes bread to rise, absorbs odors and can be used for cleaning all sorts of stuff, including your teeth. In the body, it plays essential roles in buffering pH, aiding in digestion and neutralizing lactic acid produced during physical exertion. Much of the bicarbonate in our bodies comes from carbon dioxide, which is produced as a waste product in all cells, although some is ingested with carbonated beverages and certain types of foods.

Now a new study from the Makino Laboratory at Massachusetts Eye and Ear/Harvard Medical School and colleagues at Salus University, describes how bicarbonate also alters how we see by modifying the visual signal generated by rod and cone photoreceptors that detect light. This study is described online in the Journal of Biological Chemistry.

Within rods and cones, a small soluble molecule, cGMP, links photon absorption to the electrical activity of the photoreceptor. In the light, cGMP is destroyed and ion channels are closed. Positively charged sodium ions cease to enter the rod or cone and the membrane potential becomes more negative or hyperpolarized. Bicarbonate directly stimulates an enzyme called guanylate cyclase that synthesizes cGMP.

"By opposing the effect of light, bicarbonate limits the size of the photon response and quickens its recovery. As a result, sensitivity to light is slightly lower but our ability to track moving objects is improved," said lead author Clint Makino, Ph.D., director of the Makino Laboratory at Mass. Eye and Ear and an Associate Professor of Ophthalmology at Harvard Medical School. "An intriguing implication is that vision may change with metabolic state, although further research is necessary for confirmation. It is now known that in some types of retinal diseases, a genetic defect causes cGMP in the rods and/or cones to rise to abnormally high, lethal levels. Once lost, rods and cones are not replaced, so an irreversible blindness is the tragic outcome."

In the future, scientists in the Makino Laboratory want to investigate the possibility that controlling bicarbonate levels in the eye will slow the progress of, or may even prevent, eye diseases.

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This study was supported by NIH EY011358, EY014104, EY023980, Research to Prevent Blindness, and the Howe Laboratory Endowment of the Massachusetts Eye and Ear.

The paper is entitled: Bicarbonate Modulates Photoreceptor Guanylate Cyclase (ROS-GC) Catalytic Activity J. Biol. Chem. published March 12, 2015 as doi:10.1074/jbc.M115.650408. http://www.jbc.org/content/early/2015/03/12/jbc.M115.650408.full.pdf+html

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A pinch of baking soda for better vision?

Washington, D.C. (PRWEB) March 16, 2015

The National Resident Matching Program (NRMP) will announce results of the 2015 Main Residency Match on Match Day, March 20, at 1:00 PM ET. In 2014, more than 40,000 applicants vied for over 29,000 residency positions at institutions across the country, and the 2015 Match is expected to be even larger. Results of the Match are closely watched because they are predictive of future changes in physician manpower supply. Members of the media who would like to receive the embargoed advance data tables on Thursday, March 19, should email media@nrmp.org with your name, publication, and email address.

Match Day is an annual rite of passage for U.S. medical students and other applicants from around the world, a culmination of years of hard work and dedication. The achievement is recognized by medical schools at Match Day ceremonies across the country beginning at 12:00 PM ET on March 20. All applicants receive their Match results from the NRMP at 1:00 PM ET.

At the medical school ceremonies, students are given personalized letters showing where they matched. Its an exciting moment because it validates their years of effort and defines their future careers as physicians, says Mona M. Signer, NRMP President and CEO. We consider it a privilege to share in this life-changing day.

The Match Process The Main Residency Match process begins in the fall for applicants, usually in the final year of medical school, when they apply to residency programs at which they would like to train. Program directors review applications and conduct candidate interviews in the fall and early winter. From mid-January to late February, applicants submit to the NRMP their rank order lists of preferred programs, and program directors rank applicants in order of preference for training. The NRMP uses a computerized mathematical algorithm to match applicants with programs using the preferences expressed on their ranked lists. Research on the NRMP algorithm was a basis for awarding The Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel in 2012.

Resources: Match Data Reports & Interviews Match data reports from previous Matches are available on the NRMP Match Data page. To schedule an interview with NRMP President and CEO Mona Signer, contact media(at)nrmp(dot)org. Contact your local medical school for details on their Match Day ceremonies.

About NRMP The National Resident Matching Program (NRMP) is a private, non-profit organization established in 1952 at the request of medical students to provide an orderly and fair mechanism for matching the preferences of applicants for U.S. residency positions with the preferences of residency program directors. In addition to the annual Main Residency Match for more than 40,000 applicants, the NRMP conducts Fellowship Matches for more than 50 subspecialties through its Specialties Matching Service (SMS).

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NRMP to Release Results for More Than 40,000 Physician Residency Applicants on March 20