State of electrolytes, osmotic balance and the activity of ATPase in the lenses of selenite--induced cataracts.

ABSTRACT

Selenite-cataracts incorporated many morphological characteristics observed in human senile catracts. Progressive elevation of sodium, marked loss of potassium, several fold increment of calcium; considerable loss of magnesium levels, a dose-response reduction of total-ATPase activity and significant hydration are the important features observed in the lens during the progressive treatment of selenite. The sodium-potassium imbalance is found to be a secondary effect during the development of cataract and is suggested to bring about by an abnormal accumulation of calcium ions and inactivation of transport enzyme. The calcium activated proteases could be the promoting factor for the proteolysis and insolubilization of lens proteins in the inducement of selenite cataract. The impact of selenite on the SH containing ATPase anzymes could be the cause of impairment in energy metabolism, derangement of electrolytes and osmotic imbalance which, in turn, accelerate the cortical involvement of lens opacities.