|کد مقاله||کد نشریه||سال انتشار||مقاله انگلیسی||ترجمه فارسی||نسخه تمام متن|
|4754526||1418065||2017||4 صفحه PDF||سفارش دهید||دانلود کنید|
- 11 male pig eyes were exposed to 80Â min of 5000Â lx bright white light.
- Mean carbon monoxide levels in ophthalmic venous blood increased approximately 25%.
- Acute bright light may raise carbon monoxide levels in ophthalmic venous blood.
The physical mechanism by which light is absorbed in the eye and has antidepressant and energizing effects in Seasonal Affective Disorder and other forms of psychiatric major depression is of scientific interest. This study was designed to explore one specific aspect of a proposed humoral phototransduction mechanism, namely that carbon monoxide (CO) levels increase in retinal venous blood in response to bright light. Eleven mature male pigs approximately six months of age were kept for 7Â days in darkness and fasted for 12Â h prior to surgery. Following mild sedation, anesthesia was induced. Silastic catheters were inserted into the dorsal nasal vein through the angular vein of the eye to reach the ophthalmic sinus, from which venous blood outflowing from the eye area was collected. The animals were exposed to 5000Â lx of fluorescent-generated white light. CO levels in the blood were analyzed by gas chromatography before and after 80Â min of light exposure. At baseline, mean CO levels in the retinal venous blood were 0.43Â Â±Â 0.05Â (SE)Â nmol/ml. After bright light, mean CO levels increased to 0.54Â Â±Â 0.06Â nmol/ml (two-tailed t-test pÂ <Â 0.05). This study provides preliminary mammalian evidence that acute bright light exposure raises carbon monoxide levels in ophthalmic venous blood.
Journal: Journal of Photochemistry and Photobiology B: Biology - Volume 168, March 2017, Pages 12-15