University of Utah scientists and colleagues have used invisible infrared light to make rat heart cells contract and toadfish inner-ear cells send signals to the brain. The discovery someday might improve cochlear implants for deafness and lead to devices to restore vision, maintain balance and treat movement disorders like Parkinson's. "We're going to talk to the brain with optical infrared pulses instead of electrical pulses," which now are used in cochlear implants to provide deaf people with limited hearing, said Dr. Richard Rabbitt, a professor of bioengineering and senior author of the heart-cell and inner-ear-cell studies published in the March 15, 2011 issue of The Journal of Physiology. The studies also raise the possibility of developing cardiac pacemakers that use optical signals rather than electrical signals to stimulate heart cells. But Rabbitt says that because electronic pacemakers work well, "I don't see a market for an optical pacemaker at the present time." The scientific significance of the studies is the discovery that optical signals – short pulses of an invisible wavelength of infrared laser light delivered via a thin, glass optical fiber – can activate heart cells and inner-ear cells related to balance and hearing. In addition, the research showed infrared activates the heart cells, called cardiomyocytes, by triggering the movement of calcium ions in and out of mitochondria, the organelles or components within cells that convert sugar into usable energy. The same process appears to occur when infrared light stimulates inner-ear cells. Infrared light can be felt as heat, raising the possibility the heart and ear cells were activated by heat rather than the infrared radiation itself.
Login Or Register To Read Full Story