Abstract
Abstract: :
Purpose: Age-related macular degeneration (AMD) is one of the most important causes of blindness, and its pathogenesis remains poorly understood. Some studies have consistently shown that AMD is attributable to oxidative stress and lack of protection by the antioxidant vitamins A, C, and E. Time-of- flight secondary ion mass spectrometry (TOF-SIMS) has the ability to detect kinds and quantity of materials in relation to cells and tissues. The purpose of this study is to clarify the effect of aging on elements and vitamins in normal rat retina. Methods: We used 4-,12-, and 18-month-old normal Wistar Kyoto rats. After pentobarbital anesthesia, the eyes were enucleated. The eyeballs were put into liquid nitrogen without any fixation, cut into semithin sections, and covered with O.C.T compound. Serial semithin sections, 10 µm, were cut with a cryo-ultramicrotome and air-dried. Then positive ion images on TOF-SIMS (TRIFID, Physical Electronics, USA) images were examined with a Ga+{ source at an acceleration voltage of 15 keV. The secondary ion acceleration voltage was 4.5 keV. Results: Body weight was significantly increased in the 12- and 18-month-old rats. The serum concentrations of Na, K, Mg, P, Ca, Fe, Zn, vit. E were not significantly different in the 3 groups. In the retina, on the other hand, the ion images of Na and Ca were significantly increased in the 18-month-old rats, and K, Mg, Fe, Cu, Zn, vit. A, vit. E, and oleic acid were significantly decreased in the retina of 18-month-old rats. Conclusion: TOF-SIMS ion images of the retina show significant age differences in concentrations of Na, K, Mg, Ca, Fe, Zn, vit. A, vit. E and oleic acid.
Keywords: 554 retina • 309 aging • 508 pathology techniques