scholarly journals Stimulation of fibronectin production and deposition by chicken granulosa cells in vitro by epidermal growth factor and transforming growth factor  

Reproduction ◽  
1994 ◽  
Vol 101 (2) ◽  
pp. 375-384 ◽  
Author(s):  
E. K. Asem ◽  
R. P. Novero
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Granulosa Cells ◽  
Transforming Growth Factor ◽  
Epidermal Growth ◽  
Stimulation Of

Characterization of transforming growth factor-α receptors in the avian ovary: alterations in ligand binding to granulosa cells during follicular maturation

1996 ◽  
Vol 149 (1) ◽  
pp. 171-179 ◽  
Author(s):  
O M Onagbesan ◽  
I Woolveridge ◽  
M J Peddie
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Granulosa Cells ◽  
Binding Sites ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Α ◽  
Follicular Maturation ◽  
Igf I ◽  
Epidermal Growth ◽  
Factor Α

Abstract The presence of epidermal growth factor receptors (EGF-R) and the ligands epidermal growth factor/transforming growth factor-α (EGF/TGFα) have been reported in mammalian ovaries where they are implicated in folliculogenesis and steroidogenesis. Evidence is presented to show that authentic EGF/TGFα receptors are expressed by the avian granulosa cells. The TGFα receptors (TGFα-R) from chicken granulosa cells were characterized by specific binding of 125I-human TGFα. In this study, competition with human EGF, human TGFα, human IGF-I, human basic fibroblast growth factor (bFGF) and insulin for 125I-human TGFα binding demonstrated that the avian granulosa cell TGFα-R binds human EGF with 300-fold lower affinity than human TGFα. IGF-I, bFGF and insulin did not displace bound 125I-TGFα. Scatchard analysis showed that a single class of high-affinity binding sites is present on the granulosa cells (Kd 0·23 ± 0·009 nm). However, the number of binding sites altered during follicular maturation with a significant decline in the most mature follicle. These results go some way to explaining the basis for the changing sensitivity of avian granulosa cells to EGF/TGFα stimulation as they mature. In addition, the gonadotrophins, LH and FSH, increased the number of receptors in cultured granulosa cells and may therefore partially influence folliculogenesis and steroidogenesis through this route. Journal of Endocrinology (1996) 149, 171–179

Effects of epidermal growth factor and transforming growth factor alpha on the mouse trophoblast outgrowth in vitro

1995 ◽  
Vol 133 (6) ◽  
pp. 741-746 ◽  
Author(s):  
Toshifumi Machida ◽  
Michiyoshi Taga ◽  
Hiroshi Minaguchi
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Epithelial Cells ◽  
Conditioned Medium ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Alpha ◽  
Epidermal Growth ◽  
Factor Alpha ◽  
Endometrial Epithelial Cells

Machida T, Taga M, Minaguchi H. Effects of epidermal growth factor and transforming growth factor alpha on the mouse trophoblast outgrowth in vitro. Eur J Endocrinol 1995;133:741–6. ISSN 0804–4643 In order to analyze the involvement of growth factors in the implantation mechanism, we examined the direct effects of epidermal growth factor (EGF) and transforming growth factor alpha (TGF-α) on trophoblast outgrowth of the mouse blastocyst in vitro. ICR mouse blastocysts were cultured for 4 days on a culture plate in medium containing EGF or TGF-α or conditioned medium obtained from cultured endometrial epithelial cells. Blastocysts were also co-cultured with endometrial epithelial cells. The trophoblast outgrowth of these cultured blastocysts was observed daily and the percentage of outgrowing embryos was calculated and analyzed statistically by the chi-squared test. Analysis for the specific binding of 125I-EGF in outgrown trophoblasts was carried out by autoradiography. The coculture (days 3 and 4) and the presence of EGF (10 ng/ml, day 4), TGF-α (1 ng/ml, day 3; 10 ng/ml, days 2 and 3; 50 ng/ml, days 2–4) or conditioned medium (days 3 and 4) significantly stimulated the rate of trophoblast outgrowth. Preincubation of the conditioned medium with monoclonal anti-EGF or anti-TGF-α antibody suppressed the stimulatory effect of the conditioned medium on trophoblast outgrowth. The specific 125I-EGF binding in outgrown trophoblasts was demonstrated by autoradiography. These results suggest that EGF and TGF-α play an important role in the implantation process by directly stimulating trophoblast development. Michiyoshi Taga, Department of Obstetrics and Gynecology, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236, Japan

Augmentation by epidermal growth factor of basal and stimulated progesterone production by human luteinized granulosa cells

1989 ◽  
Vol 121 (2) ◽  
pp. 397-402 ◽  
Author(s):  
M. C. Richardson ◽  
S. C. Gadd ◽  
G. M. Masson
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Granulosa Cells ◽  
Cultured Cells ◽  
Vitro Fertilization ◽  
Human Granulosa Cells ◽  
Culture Cells ◽  
Oocyte Collection ◽  
Epidermal Growth

ABSTRACT Human granulosa cells were prepared from follicular aspirates obtained during oocyte collection for in-vitro fertilization. Following several days in culture, cells were washed and then progesterone output was measured in 2-h incubations. After culture for 3 days, incubated cells responded well to human chorionic gonadotrophin (hCG) and prostaglandin (PG) E2 with similar levels of maximum response. Exposure of cultured cells to epidermal growth factor (EGF) for 2 days (days 3–5) led to substantial increases both in basal production and in responses to hCG and PGE2 during subsequent incubations. These effects of EGF were not accompanied by measurable increases in DNA levels in cultures over this time. Results may point to a possible paracrine role for EGF-like factors modulating the activity of cells forming the early corpus luteum. Journal of Endocrinology (1989) 121, 397–402

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