Ell Death and Sexual Differentiation of the Ervous System

bstract—Sex differences in nuclear volume or neuron numer often are attributed to the hormonal control of cell death. n the spinal nucleus of the bulbocavernosus, the central ortion of the medial preoptic nucleus, and the principal ucleus of the bed nucleus of the stria terminalis testicular ormones decrease cell death during perinatal life, resulting n a male advantage in neuron number in adulthood. Conersely, males have more dying cells during development nd fewer neurons in adulthood than do females in the aneroventral periventricular nucleus of the hypothalamus. This eview discusses several limitations and unresolved issues n the literature on sexually dimorphic cell death, and identies molecular mechanisms by which gonadal steroids may ontrol cell survival. In particular, evidence is presented for he hormonal regulation of neurotrophic factors and involveent of Bcl-2 family proteins in the determination of sex ifferences in neuron number. © 2005 Published by Elsevier td on behalf of IBRO.