Kidney Na⁺, K⁺-ATPase: A Kinetic Study in Rats during Chronic Infection with Trypanosoma congolense

Abstract

Kidney microsomal Na⁺, K⁺-ATPase was studied in rats infected with Trypanosoma congolense. There was an observable loss in affinity of Na⁺, K⁺, and ATP for the enzyme in the parasitized animals, as well as a change in the energy of activation (E_a) and transition temperature. The inhibition with vanadate was significantly higher in the parasitized animals compared with that in the control indicating a change in the enzyme's index of physiological efficiency (V_max/K_m). This observation is suggestive of membrane modification in the infected group, thus enhancing permeability to vanadate.
In an allied experiment, the level of kidney Na⁺, K⁺-ATPase was observed to decline as the parasitemia became massive. This clearly indicates organ damage and the consequent release of quantities of the enzyme into the blood-stream.
The relevance of these findings to kidney pathologies during chronic-stage trypanosomiasis is discussed.