The effects of trifluoperazine on calcifying tissues in the immature rat

When the antipsychotic drug trifluoperazine is given to immature rats during stages of rapid bone development, severe localized derangement in their growth plate architecture results. In addition, 3 weeks of treatment with doses of 3 mg/kg body wt/day had marked effects on the anatomic distribution of bone mineral, and on the quantitative chemical composition of the bone matrix. Specifically, ash contents and Ca/P ratios were decreased and mineral crystals appeared larger and/or more perfect in the treated animals. The finding of decreased hexosamine content and alterations in bone lipid composition could be interpreted as specific effects of the drug on calmodulin activity.