Bilateral salpingo-oophorectomy did not appear to affect time to recurrence or overall survival. Retention of ovarian function may be an option for premenopausal women with low-grade endometrial stromal sarcomas.
Calpain, a calcium (Ca2+)-activated cysteine protease presents in several somatic mammalian cells, has been demonstrated to mediate specific Ca2+-dependent reactions including cell fusion. Because spermatozoa cells have an absolute Ca2+ requirement for penetration of oocytes, we have postulated that calpain would also be found in mammalian spermatozoa. Here we show that whole sperm homogenate and cell fractions prepared from ejaculated human spermatozoa contain calpain activity. Specific calpain inhibitors impaired this proteolytic activity. Unlike the enzyme described in somatic cells, sperm calpain was mostly particulate in nature and its activity was maximal at pH 9.0. Presence of sperm calpain was confirmed by immunoblot analysis using specific anti-calpain I and anti-calpain II antibodies. A 67 kDa calpain II protein and a 75 kDa calpain I protein were detected. Also spermatozoa contain the endogenous calpain inhibitor, calpastatin. We detected 158.8 +/- 24.5 (mean +/- SD) fmol calpastatin/mg sperm protein. Immunoblot analysis using specific antibodies showed a 68 kDa calpastatin protein located in the cytosolic fraction. This is the first demonstration that a complete calpain-calpastatin system exists in mammalian spermatozoa. Because calpain is a unique effector system for calcium-dependent processes, our data reveals a novel mechanism by which calcium exerts its regulatory functions in spermatozoa.
Insulin-like growth factors (IGFs) belong to a family of low mol. wt, single chain polypeptides inducing growth promotion and insulin-like metabolism effects and regulating both cell replication and differentiation. Recent studies in laboratory animals suggest that IGFs play an important role as intraovarian regulators in several mammalian species. The purpose of this article was to review current concepts of interactions between the IGFs and the thecal-granulosa-cell function. To provide a basic understanding of these interactions, we have first analysed data concerning biosynthesis, biochemical structure, pharmacokinetics, degradation, binding proteins and receptors for IGFs. Then we have discussed the specific interactions between IGFs and theca-granulosa-cell regulation, and analysed the significance of the relationship to the pathophysiology of some endocrine and reproductive disorders, including hyperandrogenism and female infertility.
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