Changes in serum, liver, and brain high and low molecular weight alkaline phosphatase following manganese toxicity in rats

The relationship between manganese (Mn) treatment and changes in the activities of serum, liver, and brain high and low molecular weight alkaline phosphatase (ALP) activity was investigated. Results obtained showed that every other day intrapritoneally injection of 175 µmol kg−1 Mn to male rats for two consecutive weeks produced decreased levels of liver and brain ALP activity, while a serum enzyme activity was significantly elevated. Chronic exposure to 68.7 µmol kg−1 Mn produced a significant fall in liver and brain levels of ALP activity and a rise in serum activity. Using gel filtration chromatography technique with sephacryl S300 showed that, in comparison to control, serum and liver homogenate from Mn-treated groups displayed a significant level of high molecular weight ALP, which might be considered as a potential biomarker for Mn toxicity.