Serotonin Deficiency in Infancy as One Cause of a Mental Defect in Phenylketonuria

Serotonin deficiency induced in newborn mice and maintained to adulthoodresulted in reduced ability to learn a maze. The serotonin deficiency was produced by overloading with phenylalanine plus tyrosine (to cause phenylketonuria), by feeding of reserpine, and by feeding of chlorpro mazine from birth to maturity.