Endocrinology of male and female puberty: An overview

The complex process of pubertal growth and development requires multiple mediators. This chapter presents recently described molecular mechanisms, such as the kisspeptin-GPR 54 complex, and other factors that govern changes in the level of functioning at the hypothalamicpituitary- gonadal axis that regulate the complex process of sexual development, reproductive development, and linear growth. The relationship between hypothalamic-pituitary-gonadal hormone secretion and the resultant effects on physical changes and overall growth in puberty are also described. Sex steroids, androgens and estrogens, have both direct and indirect effects on growth. Direct actions include stimulation of the bony growth plate while indirect effects occur via growth hormone and insulin-like growth factor-1. Bone mass accrual, mediated by sex steroids and growth hormone, is maximal at the late stages of puberty after peak height velocity in both sexes. The changes in bone mass accumulation, bone density, and fat and lean body mass that occur during puberty all show distinct sexually dimorphic patterns of development.