Spatial Distribution of Adenosin Nucleotides in Lenses of Species with Different Accommodative Capacities
It has been hypothesized that the lens actively participates in the accommodative process. This hypothesis is based on the presence of high ATP/ADP ratios found in total lens homogenates of accommodating lenses as opposed to non-accommodating lenses with a lower ATP/ADP ratio. To get an insight into physiological differences between lenses of high and low accommodative capacity respectively, we studied the spatial distribution of adenosin nucleotides in the lenses of species that differ with respect to their accommodative capacity. Lenses of species with a high accommodative range (chicken and turkey) and with low or no such capacity (calf, cow, rabbit and rat) were analysed. Each lens was deep frozen, separated into an equatorial ring and a central cylinder, the latter was sliced into 6 layers (anterior to posterior pole). Tissue samples were homogenized and processed for biochemical assays. The data obtained are in contradiction to the expectations: non-accommodating lenses from rats and rabbits had higher ATP ratios in the equatorial region and section 1 than accommodating lenses (chicken and turkey). In the deep cortical and nuclear region, however, the avian lenses have higher ATP ratios than the rodent and bovine lenses. This changes again in the posterior subcapsular layer.
KeywordsCentral Cylinder Accommodative Process Bovine Lens Equatorial Ring Superficial Cortex
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