Regional changes in monoamine levels and in the rate of tyrosine and tryptophan hydroxylation in 4 week old offspring of nursing mothers treated with the neuroleptic drug penfluridol

Nursing rat mothers were given penfluridol 1.0 mg/kg on days 1, 3, and 5 after delivery. The male litter-mates were killed 4 weeks after birth 30 min after treatment with an inhibitor of aromatic l-aminoacid-decarboxylase, NSD-1015, and the concentrations of noradrenaline, dopamine, and 5-hydroxytryptamine were analyzed in regional brain areas. Additionally, the accumulation of Dopa and 5-hydroxytryptophan after administration of NSD-1015 was analyzed. In the offspring of mothers treated with penfluridol a marked decrease in the rate of tyrosine hydroxylation in specific brain regions was observed. The possibility that penfluridol interacts with the development of monoaminergic mechanisms in the brain at a sensitive developmental period, and thereby induces a decreased functional activity in central monoamine neurones, especially in the limbic system, is discussed.