Levels of catecholamines in blood plasma of rabbits naturally infected with Encephalitozoon cuniculi

Catecholamines present in blood participate in regulation of a number of physiological mechanisms and at the same time reflect some pathological changes. We used a radioenzymatic method to investigate the catecholamine levels in blood plasma of 24 laboratory rabbits (females, 13 months old, weighing 3.2 +/- 0.4 kg) which were examined by the method of radial haemolysis and indirect immunofluorescence for the presence of antibodies to Encephalitozoon cuniculi antigens. The results obtained indicate that encephalitozoonosis decreases significantly the level of catecholamines in blood plasma. From the total number of rabbits investigated, 41.7 % were evaluated as seropositive. The seropositive group of rabbits exhibited a significant (p < 0.05) decrease of plasma dopamine levels (by 23.3 %). Concentrations of norepinephrine in blood plasma of rabbits decreased from 26.07 +/- 0.780 to 8.42 +/- 0.117 which is a significant decrease by 41.9%. Similar changes were recorded in the levels of plasma epinephrine (p < 0.05) in comparison with healthy individuals (de crease by 34.6 %). The results obtained showed that a marked decrease in activity of peripheral adrenergic system occurs in seropositive animals following the infection with Encephalitozoon cuniculi parasite.