Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

As the UV-B cataract and early stages of diabetic cataract in rats only touches the epithelium and anterior superficial cortex, a whole lens analysis is not meaningful, but a regional analysis with the freeze-sectioning device has to be performed. Scheimpflug photography with microdensitometric image analysis enables the scientist to discern in vivo single layers along the optical axis of the lens. UV-B cataracts (0.2 J/cm2, every 2nd day) and diabetic cataracts (Streptozotocin (STZ), 70 mg/kg BW) were induced in Brown-Norway rats. The stages of lens opacification were documented by Scheimpflug photography. 8 weeks after start of UV-B treatment and at several dates before onset of visible diabetic cataractous changes, the animals were sacrificed. The lenses were divided reproducibly into 4 or 7 parts such as an equatorial ring and several layers of the central cylinder from anterior to posterior part. The enzyme activity spectrum shows highly region related pattern that would not have been found in a whole lens analysis. Aldose reductase was activated before appearance of visible cataractous changes due to diabetes compared to normal lenses. In contrast Fructose-1,6-biphosphate-aldolase activity was lower before onset of visible changes than in normal lenses, but only within the 1st section where later visible cataractous changes of UV-B cataract could be detected.
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PMID:Regional enzymatic analysis of UV-B and streptozotocin induced diabetic cataract lens. 196 39

The specific activities of glutathione reductase (GR), EC 1.6.4.2, and aldolase, (ALD) EC 4.1.2.13, were determined in the homogenates of 60 cataractous lenses. Concentrations of certain plasma constituents and the morphological types of cataract of the patients were known. Investigations were aimed at establishing a possible correlation between enzyme activities and plasma constituents as well as between the specific activities of GR and ALD and type of cataract. A correlation between the specific activity of GR and the urea content of the blood could be identified. Results also indicated a relationship between the decrease in GR activity and the formation of cortical cataracts.
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PMID:Studies of lens enzyme activities in relation to cataract type and plasma constituents. 641 62

Royal College of Surgeons (RCS) rats have hereditary retinal degeneration in association with posterior subcapsular opacities. Cataract formation is thought to be correlated with an increase in lipid peroxidation products in the vitreous (Zigler and Hess, 1985). In order to examine the possibility that parallel changes in enzyme activity are occurring within the lens, we analysed the activity of four key enzymes and the crystallin protein profile. We compared RCS rat lenses at three different stages of cataract formation to clear lenses of the nonpigmented RCS rat, lenses from pigmented RCS rat and to normal (Fisher) rat. Our data shows that concomitant with the appearance of the RCS cataract, the ratio of the crystallins beta 1, beta H and gamma to the total lens protein was reduced. The crystallin profile of a clear RCS lens was similar to that of a normal (Fisher) lens. No significant difference in the activity of the enzymes hexokinase and glucose-6-phosphate dehydrogenase (G6PD) was found among the lenses, however the activity of glutathione reductase and aldolase was reduced in the cataractous lenses.
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PMID:Enzyme activities and crystallin profiles of clear and cataractous lenses of the RCS rat. 840 88