To investigate the relationship between the androgen receptor content of human foreskin and age-dependent physiological changes in genital development, cytosolic and nuclear androgen receptors were measured in preputial skin specimens from male subjects of various ages. Optimum incubation conditions (4 C, 20 h) were established for measurement of androgen receptors by the exchange method with the synthetic androgen ligand methyltrienolone. The number of total androgen receptor sites, cytosolic plus nuclear, was fairly constant at all ages studied. However, the androgen receptor was predominantly localized to the nuclear compartment at those developmental stages characterized by higher levels of circulating blood androgens, i.e. newborns, pubertal males, and adults. By contrast, the androgen receptor in specimens from prepubertal boys was confined almost exclusively to the cytosolic compartment. This corresponds to a time of low plasma androgen levels and quiescence in genital maturation. It is suggested that changes in the intracellular distribution of androgen receptors may bear some relationship to the sequence of normal genital growth and development with nuclear androgen receptors having major physiological importance.
The pediatrician should search carefully in a child with chest pain for evidence in the history or physical examination of an organic cause. Hemothorax is one of the pathologic processes that can present with this symptom. The differential diagnosis of hemothorax in children is reviewed.
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