Correlation of acid phosphatase but not alkaline phosphatase activity with myelination in the developing mouse brain

1. Neonatal mice received subcutaneous injections of buffer, thiourea (TU) or propylthiouracil (PTU). 2. The PTU-treated mice were sacrificed on postnatal day 14 (P14) and the TU-treated mice on P28. 3. Brain weights of the TU- and PTU-treated mice were not significantly different from the controls. 4. Acid but not alkaline phosphatase activity in the brainstem decreased after TU and PTU treatment. 5. Myelination as indicated by intensity of luxol fast blue staining was weaker in the drug-treated animals. 6. The level of myelin marker enzyme, 2',3'-cyclic nucleotide 3'-phosphohydrolase, was lower in the brainstem of PTU-treated animals. 7. The results suggest a correlation between acid phosphatase but not alkaline phosphatase activity with myelination in the developing mouse brain.