Linear regression analysis for enzyme kinetic studies in toxicant interactions

A new method based on linear regression of per cent modulation in enzyme activity over substrate concentration is proposed to give an interpretative base to the influence of more than one modulator/inhibitor/toxicant, a situation commonly met with in toxicological studies-toxicant interactions. Advantages of this method over the classical kinetic methods are discussed in detail using brain Mg2+ ATPase activity of the fish Tilapia mossambica under in vitro regimes of hexachlorocyclohexane and malathion.