To investigate prolactin gene expression in human ovarian follicular cells.
RNA was isolated from follicular cells obtained at the time of transvaginal oocyte retrieval from patients after controlled ovarian hyperstimulation. The RNA was subjected to reverse transcription and polymerase chain reaction (RT-PCR) using prolactin-specific primers. The RT-PCR products were analyzed by gel electrophoresis, followed by Southern blot analysis using prolactin-specific probes.
Department of gynecology and obstetrics research laboratory.
Women undergoing controlled ovarian hyperstimulation followed by transvaginal oocyte retrieval.
Controlled ovarian hyperstimulation followed by transvaginal oocyte retrieval. Expression of prolactin mRNA by follicular cells.
The presence of prolactin-specific cDNA amplified by RT-PCR from RNA isolated from human follicular cells was confirmed by Southern blot analysis.
Human ovarian follicular cells are an extrapituitary site of prolactin gene expression.
"It has, for instance been located in a variety of reproductive tissues (in ovaries, the deciduas, placenta, mammary glands, testes, prostate and germ cells), immune tissues (leucocytes , bone marrow, thymus, spleen, tonsils, lymph nodes), neural tissues (brain and spinal cord, in sense organs and vitreous fluid), integumentary tissues (skin, sweat glands, sebaceous glands, hair and hair follicles) and other locations (in lachrymal glands, kidneys, in adipose and in blood endothelial cells) (see Table 1). These studies include those that show the presence of prolactin mRNA (eg. by in situ in the neural retina; Aranda et al., 2005; by RT-PCR in hair follicles, Foitzik et al., 2006; by RT-PCR in ovarian follicles, Phelps et al., 2003) and those that show the presence of immunoreactive proteins (eg. by immunohistochemistry and western blotting in capillary endothelial cells, Ochoa et al., 2001; by radioimmunoassay in adipose tissue explants, Hugo et al., 2008). "
"However, our data demonstrating the presence of prolactin peptide in lysates and supernatants of granulosa cells suggest that the ovary could be an additional extrapituitary source of prolactin. This ®nding is in contrast to an earlier study (Ohwaki et al., 1992) but is in agreement with more recent data, which demonstrated that prolactin gene expression was evident in homogenized whole ovarian samples (Schwarzler et al., 1997) and in human luteinized granulosa cells (Phelps et al., 2003). If prolactin is a local product, then its levels might be expected to exceed those in serum, and indeed the levels were found to range from 9 to 180% of serum levels in a range of matched follicles (McNatty et al., 1975). "
[Show abstract][Hide abstract] ABSTRACT: The role of prolactin in the regulation of ovarian folliculogenesis and corpus luteal function and in particular its relationship to atresia in these structures is as yet unclear. We established a model of apoptosis in which to examine the actions of prolactin.
Granulosa cells collected from IVF-flush were cultured at 0.1-0.3 x 10(6) cells/well in growth media for 48 h, placed into serum-free media for 24 h prior to dosing for 24 h. Dose responses to C2-ceramide and prolactin were performed. Cells were then treated with an apoptotic dose of C2-ceramide alone, prolactin (100 ng/ml) alone or a combination of the two. Cell death was assessed by Trypan Blue cell counting and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; Thiazolyl Blue] assay and apoptosis confirmed by morphological assessment and flow cytometry.
C2-ceramide (0-40 micro mol/l) induced a dose-dependent increase in cell death (63.8% increase at 40 micro mol/l) and, morphologically, cells exhibited classical features of apoptosis. Prolactin alone had no effect on metabolic activity or total cell number. On co- incubation, prolactin alone had no effect on cell death, whereas C2-ceramide induced an approximately 62.6% increase in apoptosis, which was inhibited in the presence of prolactin.
Prolactin may contribute significantly to early corpus luteum formation and survival by acting as a potent antiapoptotic factor for human granulosa cells.
Human Reproduction 01/2004; 18(12):2672-7. · 4.57 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.