EFFECTS OF PTERIDINES ON LUMINOL-DEPENDENT CHEMILUMINESCENCE INDUCED BY CHLORAMINE-T

Pteridines are ubiquitous in living organisms, but little is known abo ut their biological functions. Different pteridines were tested for th eir ability to modulate luminol-dependent chemiluminescence induced by chloramine-T at pH = 7.5 and at a concentration of 100 mu M for each pteridine. We observed striking differences between the compounds; whe reas reduced pteridine species were generally potent scavengers, aroma tic pteridines were weak to strong enhancers of the chemiluminescence. Taking into account the detailed chemical structure of the molecules, by multiple linear regression analysis a simple index was constructed that allows prediction of the effects of the different pteridines wit h high accuracy (linear correlation coefficient between predicted and observed values r = 0.89). The effects of different pteridines on free radical-induced chemiluminescence might bear biological significance since, for example, certain pteridines take part in enzymic reactions involving free-radical intermediates, or are related to the activation of macrophages in close relationship with the oxidative burst.