Sexual dimorphism in growth as measured by microknemometry: different responses to XXXX and exogenous GH administration.

@entity2338 @entity251 @entity444 @entity2135 @entity1017 @entity35 @entity5542
To monitor growth, a novel noninvasive leg length measurement technique, called microknemometry, which allows daily observation of tibial growth rate, was used. The @entity35 exhibits a striking sex-related difference in postpubertal growth. Exogenous GH administration results in a sexually dimorphic response, affecting growth in normal young female @entity35 but not in males. Here we investigated how chronic @entity2338 affects male and female @entity35 growth patterns. The degree of growth rate recovery was investigated after exogenous GH administration to chronically deficient males and females. The deficiency was induced by neonatal @entity5542 ( @entity5542 ) treatment. Since the neonatal gonadal environment plays an important role in the dimorphic growth pattern, neonatal androgenization of female @entity35 with @entity251 or neonatal feminization of male @entity35 by castration was performed and the growth pattern monitored. @entity5542 treatment decreased pituitary GH content and plasma @entity2135 levels in both sexes, but caused a less marked reduction of female @entity35 tibial growth and body @entity1017 than in males. Additionally, only @entity5542 -treated males showed decreased pituitary LH content, so that the dimorphic action of @entity5542 on the @entity444 may contribute to the observed differences in growth rate. GH administration was able to increase leg length in all @entity5542 -treated @entity35 but was more effective in females, despite a similar restoration of plasma @entity2135 levels in both sexes. Although neonatal castration of male @entity35 resulted in a reduction of tibial growth rate and body weight, and neonatal @entity251 administration to female @entity35 caused a slight increase in body weight, a complete modification of the gender-dependent growth pattern was not achieved, indicating that appropriate steroid environment is also needed in puberty and adulthood.
