Androgens Prevent Normally Occurring Cell Death in a Sexually Dimorphic Spinal Nucleus

• Published in: Science (American Association for the Advancement of Science) Vol. 229; no. 4714; pp. 671 - 673
• Main Authors: Nordeen, E. J., Nordeen, K. W., Sengelaub, D. R., Arnold, A. P.
• Format: Journal Article
• Language: English
• Published: United States The American Association for the Advancement of Science 16-08-1985; American Association for the Advancement of Science
• Subjects: Adulthood; Androgens; Androgens - pharmacology; Animals; Axons; Cell death; Cell Survival - drug effects; Critical periods; development; Female; Male; Mating behavior; Motor neurons; Motor Neurons - physiology; Neuroendocrinology; Neurons; Penis - innervation; Physiological aspects; Physiological regulation; Rats; Rattus; Reproduction; Sex Characteristics; sex differences; Sex linked differences; spinal cord
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.4023706

The spinal nucleus of the bulbocavernosus (SNB) contains many more motoneurons in adult male rats than in females. Androgens establish this sex difference during a critical perinatal period, which coincides with normally occurring cell death in the SNB region. Sex differences in SNB motoneuron number arise primarily because motoneuron loss is greater in females than in males during the early postnatal period. Perinatal androgen treatment in females attenuates cell death in the SNB region, reducing motoneuron loss to levels typical of males. The results suggest that steroid hormones determine sex differences in neuron number by regulating normally occurring cell death and that the timing of this cell death may therefore define critical periods for steroid effects on neuron number.