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University of Kent neurophysiologist discovered that aging results in reduction in sensitivity to light in the part of the brain that controls circadian rhythms- suprachiasmatic nucleus (SCN). This could improve treatments that improve physiological and behavioural circadian clock ‘re-setting’ in adult.
Dr Gurprit Lall, of the University’s Medway School of Pharmacy, and the other members of the research team explored alterations in one of the pathways in the part of the brain controlling circadian rhythms and discovered a glutamate receptor (NMDA), used to transmit light information, became less effective in resetting the circadian clock as part of the aging process.
This structural change in the glutamate receptor was responsible for the decline in light response. A subunit of the NMDA receptor exhibited a marked decrease in presence among older mammal, indicating an age-associated change in structural configuration. The aging SCN suffers from a structural reorganisation of its light receiving components; which impair its function in setting and maintaining a stable circadian rhythm.
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