Testis-Like Steroidogenesis: RESULTS(1)

20 Apr

Gonadal Size and Testosterone Concentrations in Plasma and Gonads

In autumn, when the animals are reproductively inactive, the ovarian portion exists as a small cap of tissue. At this time, in contrast, the interstitial gland reaches its maximum size, which is significantly greater (p < 0.002), by about 2-fold, than during the spring period of reproductive activ-ity—whentheovarianportionincreasesin sizaaffollieles mature and the interstitial gland decreases in size (Table 1). Body weight does not differ significantly between the two seasons (data not shown). buy cheap antibiotics

Females in autumn had a significantly higher concentration of circulating testosterone than pregnant females in spring (p < 0.01, Table 1). Plasma androstenedione did not differ significantly (p > 0.2) between these two groups. These levels of testosterone in autumn approached those of the two males collected in this season (Table 1). Interestingly, the one nonpregnant female in the spring had one of the highest plasma testosterone concentrations of all of the females examined (Table 1; Fig. 2). Among the reproductive females, there were no differences in plasma testosterone between the 3 that were immediately postpartum (within 24 h of parturition) and the 11 pregnant females, and plasma testosterone did not correlate with stage of pregnancy (as judged by the size of the fetoplacental units).
Fig1Testis-Like SteroidogenesisFIG. 1. External genitalia of adult female (left) and adult male (right) Talpa euro-paea. The female clitoris is traversed by a centrally located urethra. Note the typically larger ano-genital distance of the male. Scale bar represents 5 mm.

Fig2Testis-Like SteroidogenesisFIG. 2. Relationship between plasma testosterone and total gonadal testosterone in male and female moles during spring and autumn. Note that plasma testosterone, but not total testosterone, was available for two pregnant females in spring (< 0.1 and 0.41 ng/ml), one female in autumn (0.8 ng/ml), and one male in autumn (1.5 ng/ml). Consequently, these data have been omitted from this figure.