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The activity of GnSI/AF was measured in pig follicular fluid (pFF) from 58 individual follicles of various sizes, by bioassay using rat pituitary cells, to investigate the relationship between gonadotrophin surge inhibiting/attenuating factor (GnSI/AF) activity and follicular development. In addition, the correlation between GnSI/AF and inhibin activities and the content of sex steroids (oestradiol, progesterone and testosterone) of follicles was examined. The activity of GnSI/AF in pFF varied significantly (0.155-1.69 U microliter-1) with size of the follicle. The activities (mean +/- SEM) were intermediate and constant in follicles with diameters from 3 to 5 mm (0.583 +/- 0.080 U microliter-1, n = 24), were higher and reached the highest value in follicles with diameters between 6 and 8 mm (0.863 +/- 0.068 U microliter-1, n = 21), and were lower, reaching the lowest value in follicles with diameters of 9 and 10 mm (0.401 +/- 0.089 U microliter-1, n = 13). In contrast, inhibin activity was almost constant during the development of follicles, although individual values varied from 0.9 to 2.5 U microliters-1. For follicles with diameters of 4-8 mm, inhibin activity was 1.754 +/- 0.042 U microliters-1 (n = 39); activity was higher in the smallest follicles with diameters of 3 mm (2.063 +/- 0.015 U microliters-1, n = 6) and was lower in follicles with diameter of 9 mm, reaching the lowest value in follicles with diameter of 10 mm (1.176 +/- 0.068 U microliters-1, n = 7); inhibin activity was not significantly correlated with GnSI/AF activity.(ABSTRACT TRUNCATED AT 250 WORDS)

A novel method for purifying dispersed porcine theca cells, with less than 3% granulosa cell contamination, was developed by the repeated use of mechanical and enzymatic procedures. The steroidogenic criteria used for the identification and purity evaluation of both theca and granulosa cells were also improved. Purified theca and granulosa cells from medium-sized follicles displayed steroidogenic differences when they were cultured in the presence of 10% fetal bovine serum: (1) the theca cells synthesized oestradiol (239.1 +/- 35.1 pg ml-1 per 2.5 x 10(5) cells in 40 h), but the granulosa cells did not synthesize it unless aromatizable androgens were added; (2) theca cells synthesized androstenedione (73.2 +/- 14.4 ng ml-1 per 2.5 x 10(5) cells in 40 h), but granulosa cells did not; (3) FSH did not affect progesterone production in theca cells; (4) the theca cells secreted androstenedione for up to 48 h; and (5) FSH significantly stimulated progesterone production in granulosa cells during a culture for 40 h (P < 0.05), but not during culture for 12 h. The lack of response to FSH was used as a reliable, functional indicator of the purity of porcine theca cells. However, this criterion proved not to be useful for cells cultured for 12 h; porcine FSH had no effect on the progesterone production of theca cells co-cultured for this time with as many as 20% granulosa cells. However, after co-culturing for 40 h, this criterion resulted in the detection of only 3% granulosa cell contamination.(ABSTRACT TRUNCATED AT 250 WORDS)

The c-kit proto-oncogene encodes a transmembrane tyrosine kinase receptor and was shown to be allelic with the white-spotting locus (W) of the mouse. Mutations at the W locus have pleiotropic effects on the development of hematopoietic stem cells, melanoblasts, and primordial germ cells. In order to elucidate the role of c-kit protein in gametogenesis and oocyte maturation, we have examined immunohistochemically the expression of c-kit in the ovaries of mice at late fetal and postnatal stages, and in early embryos. By the avidin-biotin-peroxidase (ABC) method using rat anti-mouse c-kit monoclonal antibody, the c-kit protein was detected in ovaries after the time of birth, but not before. The expression of c-kit was observed mainly on the surface of oocytes, but not in granulosa cells nor in interstitial regions. Oocytes of primordial to fully grown Graafian follicles showed the c-kit protein. When ovulation was induced by hCG, the expression of c-kit in ovulated unfertilized oocytes was weaker than in oocytes of Graafian follicles. In 1-cell embryos the c-kit protein was still observed, but with cell division its expression further decreased, and it was not detected in embryos of 4-cell, 8-cell, and morula stages. In summary, the highest expression of c-kit was observed on the surface of oocytes arrested in the diplotene stage of meiotic prophase. With ovulation and the resumption of meiotic maturation, its expression declined. These results suggest that the c-kit protein may play some role in meiotic arrest, oocyte growth, and oocyte maturation.

Effects of interleukin-1 (IL-1) on FSH-induced differentiation of immature porcine granulosa cells in vitro were examined in short-term (48-h) cultures. IL-1 inhibited FSH induction of aromatase activity and of LH-stimulated cAMP accumulation by granulosa cells. Both these inhibitory actions of IL-1 were concentration-dependent. Significant inhibitory effects were observed with as low as 0.05-0.25 ng/ml of IL-1, with maximal effects at 25 ng/ml. IL-1 also significantly inhibited increases in [125I]iodo-LH binding and progesterone secretion induced by FSH, as well as reducing basal levels of aromatase activity and LH-stimulated cAMP accumulation. Studies on the mechanisms of IL-1 actions on FSH-induced differentiation of immature porcine granulosa cells revealed that IL-1 reduced cAMP accumulation by the cells in response to FSH in a time- and concentration-dependent manner. IL-1 also inhibited induction of aromatase activity and LH-stimulated cAMP accumulation induced by dibutyryl cAMP, suggesting that IL-1 also affects the steps distal to cAMP generation. In contrast, IL-1 had no effect on progesterone secretion induced by dibutyryl cAMP, suggesting that post-cAMP steps of progesterone secretion were unaffected by IL-1.

The image diagnosis of a gynecologic tumor is progressing with the propagation of magnetic-resonance imaging (MRI), fast X-ray computed tomography (CT), and transvaginal probe. We introduce you the role which an image diagnosis should play in the decision of the therapeutic plan and the evaluation of the therapeutic effect of a uterine cervical cancer, a uterine endometrial cancer, and an ovarian cancer. In a uterine cervical cancer, MRI is useful to grasp the stage and the tumor size, and contributes toward determining a therapeutic plan. In addition, we may guess the response to the therapy, and judge the existence of a residual tumor during or immediately after an irradiation or an intraarterial injection. In a uterine endometrial cancer, MRI will contribute toward demonstrating a cervical invasion and toward assessing a myometrial invasion, therefore may help us to modify a therapeutic plan. To stage an ovarian cancer, it is necessary to visualize a small disseminated lesion. However, as all imaging modalities has a limitation to reveal the small disseminated nodules, they will not replace probe laparotomy. The probability of X-ray CT to take the place of second-look operation by an improvement has been suggested. MRI is poor at the visualization of a dissemination, however it is sometimes helpful for the evaluation of the therapeutic effect of a localizing tumor with demonstrating the changes of the signal intensity. We suppose that also an image diagnosis leaves room for expectation to contribute toward deciding the therapeutic plan of an ovarian cancer.

In an assay for thyroid-stimulating antibodies, in which FRTL-5 thyroid cells were incubated with crude immunoglobulin (Ig) fractions precipitated from serum with 15% polyethylene glycol, significant increase in cAMP production was elicited by the samples from 25 (35.7%) out of 70 pregnant women. The highest value was 529.5%. There was a close correlation between thyroid stimulating activities and serum hCG concentrations (r = 0.708, P less than 0.001). When 125I-hCG was added to serum from pregnant women, about 20% of the radioactivity was incorporated into the Ig fractions. hCG preparations within a range of concentrations of 30-300 IU/m elicited 2.3-16.5 times increase in cAMP in a dose-dependent manner. Nine pregnant women with serum TSH concentrations less than the lower limit of the normal range (less than 0.25 mU/l) displayed significantly higher values for both thyroid stimulating activities and serum hCG concentrations (P less than 0.001, respectively) compared with those who had normal TSH levels in serum. These data suggest that hCG or its variant may stimulate the thyroid sufficiently to suppress secretion of TSH from the pituitary in some pregnant women.