G. Vandoren

Heterogeneity of α2u-globulin gene products in different translational systems, plasma and urine

α2u‐Globulin, an androgen dependent rat urinary protein, displays considerable microheterogeneity. To explore whether this microheterogeneity of α2u‐globulin in male rat urine is related to the heterogeneity at the level of the genes encoding this protein, or whether it is due to post‐translational processing we studied the α2u‐globulin mRNA translation products in rabbit reticulocyte and Xenopus oocytes. Comparison of the α2u‐globulin species produced in these two heterologous systems with those observed in plasma and urine indicates that the heterogeneity of this protein in urine is mainly due to heterogeneity at the level of the corresponding mRNAs.

Neonatal imprinting of serum transcortin levels in the rat

Abstract The role of neonatal androgen in the sexual difference of rat serum transcortin levels was investigated. Male rats castrated at birth develop in adult life transcortin levels similar to those of female animals spayed at birth or to those of adult intact female animals. Animals of both sexes gonadectomized at birth and treated neonatally with a single injection of testosterone propionate show transcortin concentrations significantly lower than those of intact female animals.

Role of the hypothalamo-hypophyseal axis in neonatal androgenisation and its postpubertal expression.

Abstract Neonatal impregnation with gonadal steroids permanently affects protein synthesis and enzyme activity in a score of peripheral organs. Many, if not all, of these neonatal effects, however, do not come to expression in the absence of the pituitary or after disruption of the hypothalamo-hypophyseal axis. It may be hypothesized that during the neonatal period of differentiation gonadal hormones permanently change the production or secretion of known or unknown hypophyseal hormones. At this point the question should be asked whether all neonatal effects of gonadal hormones are mediated by the same or by different hypophyseal factors? A survey of the pertinent literature reveals 6 clusters of proteins and enzymes whose concentration or activity in adulthood is jointly, but in a distinct way, regulated by pituitary and gonadal hormones. Proteins belonging to two of these clusters were studied longitudinally by radial immunodiffusion in hypophysectomized rats and in hypophysectomized rats with pituitary implants and this before and after treatment with CB 154. Prolactin seems to be the mediator of the effects of gonadal hormones on serum transcortin levels.