We have studied the expression of epidermal growth factor (EGF) and EGF receptors (EGF-R) in isolated human trophoblast cells at various stages of differentiation and also the biological significance of the EGF/EGF-R autocrine and paracrine mechanism. Cytotrophoblast cells were isolated from human placental tissues of 6-9 weeks of gestation. Trophoblast cells underwent morphological and functional differentiation during in vitro culture. The expression of EGF and EGF-R protein and mRNA was studied in trophoblast cells cultured for 0-5 days, using immunocytochemical staining, and reverse transcription and polymerase chain reaction. Monoclonal antibodies (mAbs) against EGF and EGF-R showed specific staining in trophoblast cells at all stages of differentiation. Both EGF and EGF-R gene transcripts were detected in RNA samples isolated from trophoblast cells at all stages. These data suggest the presence of an EGF/EGF-R autocrine and paracrine mechanism in human trophoblast cells. Next, we examined the biological significance of this mechanism on trophoblast cell differentiation in vitro. EGF added to the culture medium significantly increased human chorionic gonadotrophin-beta (hCG-beta) secretion and, more importantly, anti-EGF neutralizing mAbs significantly reduced both hCG-beta and human placental lactogen secretion from trophoblast cells in culture. All these results suggest that human trophoblast cells express both EGF and EGF-R, and that EGF may play an important role in the functional differentiation of human trophoblast cells.
This study aimed to evaluate the current status of reproductive disorders as long-term complications in adolescent and young adult (AYA) cancer patients by comparing survivors of childhood-onset with those of AYA-onset cancer in Japan.We conducted a national survey of AYA cancer survivors and healthy AYAs and analyzed the results from survivors who underwent chemotherapy and reported fertility problems as their current concern.Among all of the childhood-onset survivors, 27 (35.5%; nine males [28.1%] and 18 females [40.9%]) listed reproduction fertility problems as their current concern. Among all AYA-onset survivors, 25 (69.5%; 1/4 males [25.0%] and 24/32 females [75.0%]) listed these problems as a current concern. In contrast, 96.3% (26/27) of all childhood-onset cancer survivors and 68.0% (17/25) of all AYA-onset cancer survivors who received chemotherapy listed these problems as a current concern.A considerable number of both childhood-onset and AYA-onset cancer survivors, and especially those who had undergone chemotherapy, reported reproductive dysfunction as a delayed complication. It is vitally important to establish a supportive care system both for the patients whose fertility was abolished after the completion of cancer treatment and prophylactically for patients before they begin treatment.
ABSTRACT The administration of thyrotrophin-releasing hormone (TRH) causes a variety of dopamine-related biological events. To understand the specific role of TRH on rat hypothalamic dopamine neurones, we examined the in-vivo effects of intraventricular (i.c.v.) infusion of TRH on the release and synthesis of prolactin in the rat pituitary gland and on the changes in binding of [ 3 H]MeTRH and dopamine turnover rates in rat hypothalamus. We have also examined the in-vitro effects of TRH on the release of [ 3 H]dopamine from dispersed tuberoinfundibular dopamine neurones. Female rats were treated with i.c.v. infusions of 1 μmol TRH/l daily for 1, 3 and 7 days using Alzet osmotic pumps. Following 7 days of treatment the serum prolactin concentrations were significantly decreased. A reduction in hypothalamic TRH-binding sites (B max ) was also apparent but the dissociation constant ( K d ) was unaffected. Northern blot analysis of total RNA isolated from the pituitary glands of control animals using 32 P-labelled prolactin cDNA as a probe indicated the presence of three species of prolactin gene transcripts of approximately 3·7, 2·0 and 1·0 kb in size, and these were decreased by TRH treatment. We examined the turnover rate of dopamine in the rat hypothalamus when TRH was administered i.c.v. for 7 days. There was a significant increase in 3,4-dihydroxyphenylacetic acid/dopamine ratio with TRH treatment. Moreover, exposure to TRH stimulated [ 3 H]dopamine release from rat tuberoinfundibular neurones in a time- and dose-dependent manner. Dopamine receptor antagonists such as SCH23390 and (−)sulpiride, and other neuropeptides such as vasoactive intestinal peptide and oxytocin did not affect TRH-stimulated [ 3 H]dopamine release. These data suggest that i.c.v. administration of TRH might decrease both prolactin secretion and accumulation of prolactin gene transcripts in the pituitary by stimulating dopamine release from tuberoinfundibular neurones. Journal of Endocrinology (1992) 133, 59–66
We have cloned a novel brain‐specific inward rectifier K + channel from a mouse brain cDNA library and designated it MB‐IRK3. The mouse brain cDNA library was screened using a fragment of the mouse macrophage inward rectifier K + channel (IRK1) cDNA as a probe. The amino acid sequence of MB‐IRK3 shares 61% and 64% identity to MB‐IRK1 and RB‐IRK2, respectively. Xenopus oocytes injected with cRNA derived from this clone expressed a potassium current which showed inward‐rectifying channel characteristics similar to MB‐IRK1 and RB‐IRK2 currents, but distinct from ROMK1 or GIRK1 current. However, the single channel conductance of MB‐IRK3 was ∼ 10 pS with 140 mM extracellular K + , which was distinct from that of MB‐IRK1 (20 pS). MB‐IRK3 mRNA expressed specifically in the forebrain, which clearly differed from MB‐IRK1 and RB‐IRK2 mRNAs. These results indicate that members of the IRK family with distinct electrophysiological properties express differentially and may play heterogenous functional roles in brain functions.
The aim of this study was to compare the effects of pre-surgical medication with dienogest or leuprorelin on post-surgical ovarian function.We conducted an exploratory study in two centers in Japan that comprised 30 patients with ovarian endometrial cysts for whom surgical excision was planned. Patients were enrolled and divided into pre-surgical medication groups with dienogest or leuprorelin for 12 weeks. Thereafter, patients were treated by laparoscopic cystectomy. The primary outcome was ovarian function post-surgery, as assessed by serum anti-Müllerian hormone (AMH) level, antral follicle count (AFC) and resumption of menses. Secondary outcome was the effect of pre-surgical medication, as assessed by the size of endometrial cysts and visual analog scale (VAS) score. Serum AMH, AFC, size of endometrial cysts, and VAS scores were measured at baseline (before medication), after medication (1 day before surgery), and at 4 and 12 weeks post-surgery.Serum AMH levels did not change after pre-surgical medication with either dienogest or leuprorelin. Although AMH decreased after surgery, it recovered by 12 weeks post-surgery in both groups with no statistically significant difference. Mean AFC did not change after surgery in either group. Menses returned by 12 weeks post-surgery in all patients except for those who were pregnant. The rate of reduction of endometrial cyst volume did not differ between the groups. Both dienogest and leuprorelin were associated with substantial reductions in VAS scores.There were no statistically significant differences between pre-surgical medication with dienogest and leuprorelin in post-surgical ovarian function. Both medications were effective in reducing endometrial cyst volume and VAS score.
