The influence of oxonate-induced hyperuricemia and allopurinol on behavioral reactions of random-bred mice.

Background: Purine metabolism specificity, namely the high level of uric acid in the blood, is considered to be significant in the appearance of intellectually-developed primates, as well as in later periods of human development, for personal activity and achievements and even for the formation of genius. Nowadays hyperuricemia is mostly associated with the pathogenesis of hypertension and metabolic syndrome. Its influence on the central nervous system is predominantly set aside.

Methods: The behavioral reactions of random-bred mice with uricase inhibition due to potassium oxonate or xanthine oxidase suppression with allopurinol for three weeks were investigated.

Results: Potassium oxonate reduced signs of anxiety in the elevated plus maze. A positive correlation appeared between latency to enter a dark arm and uricemia, so anxiety reduction can be associated with uric acid metabolism changes. Allopurinol reduced anxiety that was not related to the metabolic changes of uric acid, so the involvement of changes in uric acid precursor concentrations cannot be excluded. Potassium oxonate but not allopurinol reduced immobility in a tail suspension test. There was a tendency to increase the duration of swimming to exhaustion against the potassium oxonate background. At the same time, potassium oxonate reduced research activity in the combined open field test and increased the vegetative maintenance of behavioral responses. Allopurinol did not change the results of this test.

Conclusions: A reduction in anxiety and depression level and a tendency to augment physical performance against the potassium oxonate background partly conform to the beneficial evolutionary role of hyperuricemia.