Histo-autoradiographic study of a testosterone target organ, the epididymis of the lizard (Lacerta vivipara), after administration of 3H-17 beta-estradiol]

[6,7 3H] oestradiol-17 beta was injected into castrated male viviparous lizards in order to compare retention of this steroid to that of testosterone during the period of sexual activity. Retention of the isotope in epididymis was greater than in blood, lung and stomach. Radioautographs of epididymis indicated that oestradiol or a metabolite was concentrated in cell nuclei and over discharged secretory granules as was observed with testosterone. Reason of such binding is not yet known.     

Ultrastructural study of the pseudopregnant rat luteal cell following the effect of luteinizing hormone and of 2 inhibitors of synthesis (amino-glutethimide and cycloheximide)]

Incubation of ovaries from pseudopregnant rats have been performed with the gonadotropin LH and with two inhibitors, aminoglutéthimide and cycloheximide for periods comprised between 1 and 6 hours. Then the luteal cells have been studied with electron microscope. Measurements in have been used to express the variations in volume of two organels, mitochondria and lipid droplets. The principal modifications induced by these compounds bear on the mitochondria. Treatment with LH is followed by an increase in the volume of individual mitochondria resulting probably of fusion of organels. Treatments with the inhibitors are followed by reduction in the volume of individual mitochondria and in the total volume of mitochondrial apparatus. Mixed treatments using LH and an inhibitor allow to obtain organels of intermediate size. Volume of lipids is increased by incubation with LH and probably decreased by the inhibitors. Smooth endoplasmic reticulum shows rearrangements with the various treatments. It seems not convenient to extend incubations over 4 hours in order to avoid cytolysis.     

Changes in epididymal protein synthesis during the sexual cycle of the lizard, Lacerta vivipara

During its annual cycle, the lizard epididymis undergoes strong modifications of the secretory epithelium. These modifications previously were classified into 10 stages. The present study gives the biochemical basis of these modifications. Several parameters, such as the quantity of soluble proteins, rates of protein synthesis, and electrophoretic profiles of newly synthesized proteins and of in vitro RNA translation products were compared at 8 stages. Two-dimensional gel electrophoresis of newly synthesized tissue proteins showed that the synthesis of about 20 proteins fluctuated during the cycle. Furthermore, it revealed that the protein band L of molecular weight 19,000 identified in one-dimensional (1-D) electrophoresis was composed of at least 10 proteins. Their rate of synthesis paralleled the concentrations of their mRNA evaluated with in vitro translation. This could indicate that in this system protein synthesis is regulated by mRNA concentrations. The present analysis has confirmed that 4 different phases characterize the annual evolution of the lizard epididymis: regeneration, onset of secretory activity, hypersecretion and involution. Well-defined, newly synthesized proteins would characterize some of these phases, and could be used as markers for future detailed analysis of epididymis control.