9729246 JACKSON The nigrostriatal dopamine pathway is an anatomically and chemically distinct and important component of the motor control system in mammals. The prenatal development and physiological function dopaminergic neurons in this pathway is known to be accelerated in female rats as compared to males, and this sex difference does not appear to be dependent on steroid hormones. Little is currently known about the underlying mechanism of the more rapid maturation of this pathway in females, whether other types of cells in this system show similar sexual differences, or whether these early differences persist during postnatal development and adulthood. This study seeks to determine if dopamine and other neurotransmitters have regulatory effects on neuronal growth and synapse formation in this system, and to characterize the range of the affected neuronal types at both pre- and postnatal times. The results of this research will enhance our understanding of how hormone-independent gender differences arise in this system, and whether these differences persist during postnatal development.
