Experimental hypothyroidism during sexual development Testes size and number of spermatozoa in adulthood are determined by postnatal/pubertal proliferation of seminal tubule somatic cell constituents, the Sertoli cells. Cessation of proliferation of Sertoli cells during early development occurs concomitantly with formation of their terminally differentiated population. Transient experimental hy...

A window of opportunity for maternal programming of neonatal development is open in the first few days of life as a consequence of nursing. Colostrum (first milk) supports neonatal development by providing a conduit for delivery of milk-borne bioactive factors, exemplified by relaxin, from mother to offspring as proposed in the lactocrine hypothesis. Relaxin, a prototypical milk-borne bioactive...

THE DEVELOPMENT OF THE MAMMALIAN REPRODUCTIVE SYSTEM INVOLVES: (1) an indifferent or ambisexual stage, in which both the male (Wolffian) and female (Mullerian) duct systems are present; (2) sexual differentiation, in which the phenotypic sex is expressed by the enhancement of Mullerian structures in the female and Wolffian structures in the male and reciprocal suppression of the opposite duct s...

Alcohol use affects all three parts of the hypothalamic-pituitary-gonadal (HPG) axis, a system of endocrine glands and hormones involved in male reproduction. Alcohol use is associated with low testosterone and altered levels of additional reproductive hormones. Researchers are investigating several potential mechanisms for alcohol's damage. These mechanisms are related to alcohol metabolism, a...

The reproductive system presents some of the best examples of programmed cell death, which is to be expected considering the dramatic cycles of tissue growth and regression in females. Hormones from the pituitary gland, gonads and uterus are responsible for coordinating cycles in which the preservation of cell survival and inhibition of apoptosis are important. In the ovary, atresia regulates t...

This review summarizes the epidemiology of cancer of the female reproductive system and associated lifestyle factors. It also assesses the available evidence for occupational factors associated with these cancers. Cervical, endometrial, and ovarian cancers are relatively common, and cause significant cancer morbidity and mortality worldwide, whereas vulvar, vaginal, fallopian tube cancers, and ...