Persistent vaginal cornification in mice treated with estrogen prenatally.

Twelve of 14 female mice of the ICR strain which had received a single injection of 50 mug estradiol-17beta on day 17 of fetal life exhibited irreversible cornification or stratification of the vaginal epithelium which persisted after ovariectomy until sacrifice performed 42-48 days later. Eight of the 12 mice had corpora lutea in their ovaries removed at 3-5 months of age. A similar injection of estradiol on day 15 of fetal life induced irreversible cornification or stratification of the vaginal epithelium in 6 of 12 females and only one of the 6 had corpora lutea in its ovaries when removed at 3-5 months. Mice given the same dose of estradiol on the day of birth or at 3 days of postnatal age invariably had ovaries bearing follicles of varying sizes and hypertrophied interstitial tissue but no corpora lutea. Changes in the vaginal epithelium in these animals were less remarkable as compared to that in prenatally treated mice.     

Progestin and estrogen receptors: characterization and localization in rat submandibular glands, with special reference to epidermal growth factor

By using progestin (P) and estrogen (E), the localization and characterization of both steroid receptors were examined in the submandibular gland (SMG) of 6-week-old immature castrated rats, with special reference to localization of epidermal growth factor (EGF). In the castrated male and female rats, both 3H-estradiol-17 beta (3H-E2 beta) and 3H-promegestone (3H-R5020) bound to SMG cytosol with high affinity and low capacity. These values were similar to those reported for other tissues. However, E-treatment after castration inhibited the specific binding. In sucrose density gradient ultracentrifugation, it was found that P receptors in both castrated males and females had a sedimentation coefficient of 7S, whereas E receptors had sedimentation coefficients of 4S and 7S. A histochemical study of the SMG of castrated male and female rats showed that the E-peroxidase complex (EPC)- and P-peroxidase complex (PPC)-stained cells were predominantly located in the epithelium of the duct system including the excretory duct and the granular convoluted tubules. Few cells were located in the intercalated duct, and none were found in the acinus. EGF-immunoreactive cells were also located in the epithelium of the same tissue region as in PPC- and EPC-stained sections. Moreover, E-treatment after castration inhibited the intensity of staining and immunoreactivity. These results clearly suggest that rat SMG contains specific P and E receptors which are mainly located in the epithelial cells of the duct system in which EGF-containing cells are identified. We discussed the possibility that P and E might affect EGF immunoreactivity, which reflects EGF production, through their receptors in the epithelium of the duct system.     

Influence of estrogen administration on the growth response to growth hormone (GH) in GH-deficient mice

In women who are growth hormone (GH) deficient, exogenous estrogens increase the dosage of GH that is needed to normalize circulating levels of insulin-like growth factor (IGF-1). Serum IGF-1 derives mostly from the liver, and it is unknown whether the peripheral effects of GH are also impaired by estrogens. Because the ultimate effect of GH is longitudinal growth, we have investigated the influence of estrogen administration on the growth response to recombinant mouse GH therapy in prepubertal GH-deficient (GHD) GHRH knockout (GHRHKO) female mice. Twenty-four GHRHKO female mice (4 animals/group) were treated for 4 weeks (from the second to sixth week of age) with the following schedules: Group I, GH only (25 microg/day); Group II, subcutaneous (sc) ethynil estradiol (EE) (0.035 ES01247g/day); Group III, GH + scEE; Group IV, oral (po) EE (0.035 microg/day); Group V, GH + poEE; Group VI, placebo. At the end of the treatment period, we measured uterine weight, total body weight (TBW), body length (nose-anus, N-A), and femur length. In addition, serum IGF-1 levels were measured. Uteri of mice treated with oral or scEE showed similar increases in weight. There was no difference in the increase in longitudinal growth parameters between mice treated with GH alone or with GH in association with oral or scEE. Serum IGF-1 decreased in animals treated with GH + scEE, compared with GH group, but no group was significantly different from placebo. These results show that subcutaneous or oral EE does not reduce the growth response to GH in female GHD mice.     

On protein deficiency in mice with special reference to liver nucleolar size

Summary Mice were starved for 2 days and then fed on either a protein-free diet or a 25 per cent casein diet for 7 days and then sacrificed. The former group, in contrast to the latter, decreased in weight during these 7 days and showed significantly lower weight absolute and relative (g/100 g initial body weight) of kidneys, liver and spleen. In the animals deprived of protein, the ratio between total liver nucleolar volume per nucleus and the nuclear volume was larger, than in the casein fed animals. The results suggest that the liver nucleolar apparatus reacts to a protein-free diet in principally the same way in mice as in rats.The investigation was supported by a grant from the Swedish Medical Research Foundation.     

Mechanisms of metal-salt methods in enzyme cytochemistry with special reference to acid phosphatase

Summary This review is concerned with theoretical and experimental aspects of the factors governing the localizing potentialities of cytochemical enzyme reactions that are based on the metal-salt principle, that is, the precipitation of the primary product of the enzymatic reaction by a heavy-metal ion at the enzymatic site. Special attention is given to the lead phosphate precipitation process in acid phosphatase cytochemistry. The various model systems developed for the study of the factors involved in precipitation are described and their advantages and disadvantages discussed. Furthermore, the various cytochemical methods so far used for the demonstration of acid phosphatase activity are critically evaluated in the light of the results obtained with the model systems.     

Comparison of heterogeneities of antitrinitrophenyl antibodies in strains of mice immunized by various methods.

Heterogeneity of antibodies directed against the trinitrophenyl (TNP) determinant in immunized mice was analyzed by investigating the band groups of antibodies formed by thin layer isoelectric focusing of serum. The degree of heterogeneity in C57BL/6 mice was markedly higher than that in CBA mice under the following conditions of immunization: immunization with TNP conjugated with bovine gamma-globulin or ovalbumin, interchange of these carrier proteins at the first and second injections, change of epitope density of the antigens, replacement of the hapten by dinitrophenyl group on the antigen for the secondary stimulation, and change of intervals of these injections from 15 days to five months. The degree of heterogeneity within a strain also varied with these immunizing conditions. Furthermore, the heterogeneity in C57BL/6 mice of any immunization group was greater than that in CBA mice in any group. This was also true when the heterogeneity was examined with the immune sera diluted to the same titer. These results indicate that the number of predominant clones of cells producing anti-TNP antibody after immunization is larger in C57BL/6 than in CBA mice.