Lactogenic response of cultured mouse mammary epithelial cells to mouse placental lactogen

Thórdarson, Gudmundur; Villalobos, R.; Colosi, Peter; Southard, Jonathan N.; Ógren, L.; Talamantes, Frank

doi:10.1677/joe.0.1090263

Cited by 46 publications

(23 citation statements)

References 35 publications

(41 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Studies in our laboratory (Markoff & Talamantes 1980, Thordarson et al 1986 showed that mGH causes a significant increase in -lactalbumin and casein secretion from mouse mammary epithelial cells in culture, in addition to enhancing the stimulatory effects of lactogens (mPRL and mouse placental lactogen) on the secretion of -lactalbumin and insulin-like growth factor (IGF)-binding proteins (English et al 1991, Fielder et al 1992. In lactating rats, treatment with an antiserum against rGH reduced milk yield by 50% (Madon et al 1986) and bovine GH was able to maintain lactation in rats receiving bromocriptine as well as anti-rGH injections, although at reduced levels .…”

Section: Figurementioning

confidence: 99%

Differential expression of the growth hormone receptor and growth hormone-binding protein in epithelia and stroma of the mouse mammary gland at various physiological stages

Ilkbahar

Thórdarson²,

Camarillo³

et al. 1999

Journal of Endocrinology

View full text Add to dashboard Cite

Increasing evidence suggests that GH is important in normal mammary gland development. To investigate this further, we studied the distribution and levels of growth hormone receptor (GHR) and GH-binding protein (GHBP) in the mouse mammary gland. At three weeks of age, the epithelial component of the right fourth inguinal mammary gland of female mice was removed. These animals were then either maintained as virgins until they were killed or they were mated. One group of the mated mice was killed on day 18 of pregnancy and the remaining mated animals were allowed to carry their pups until term and were killed on day 6 of lactation. At the time of death, both the intact left and the de-epithelialized right mammary glands were collected from all three groups. Some of the intact glands served as a source of epithelial cells, free of stroma. The mRNA levels for GHR and GHBP were measured in intact glands, epithelia-cleared fat pads, and isolated mammary epithelial cells. GHR and GHBP mRNAs were expressed in both the mammary epithelium and stroma. However, the levels of both GHR and GHBP mRNAs were significantly higher in the stroma as compared with the epithelium component. This increase for both mRNAs was from 3-to 12-fold at each physiological state examined. In the intact gland, both GHR and GHBP transcripts were highest in virgins, declined during late pregnancy, and the lowest levels were found in the lactating gland. GHBP and GHR protein concentrations were also assessed in intact glands and epithelia-free fat pads. Similar to the mRNAs, GHR and GHBP protein levels (means ...) in intact glands were highest in virgin mice (0·891 0·15 pmoles/mg protein and 0·136 0·26 pmoles/mg protein respectively), declined during late pregnancy (0·354 0·111 pmoles/mg protein and 0·178 0·039 pmoles/mg protein respectively), and were lowest during lactation (0·096+0·037 pmoles/mg protein and 0·017+0·006 pmoles/mg protein respectively). Immunocytochemistry utilizing specific antisera against mouse (m) GHR and mGHBP revealed that the two proteins are localized to both the stroma and parenchyma of mouse mammary glands, with similar patterns of immunostaining throughout the different physiological stages analyzed. GHR immunolocalized to the plasma membrane and cytosol of mammary epithelial cells and adipocytes, whereas the GHBP immunostaining was nuclear and cytosolic. In conclusion, we report here that GHR and GHBP mRNAs and proteins are expressed in both the epithelium and the stroma of mammary glands of virgin, pregnant, and lactating mice. In intact glands, GHR and GHBP proteins, as well as their transcripts are higher in abundance in virgin relative to lactating mice. At all physiological stages, GHR and GHBP mRNA levels are higher in the stroma compared with the parenchyma. These findings indicate that the actions of GH in the mammary gland are both direct through its binding to the epithelia, and indirect by binding to the stroma and stimulation of IGF-I production which, in turn, affects mammary epithelial developme...

show abstract

Section: Figurementioning

confidence: 99%

Differential expression of the growth hormone receptor and growth hormone-binding protein in epithelia and stroma of the mouse mammary gland at various physiological stages

Ilkbahar

Thórdarson²,

Camarillo³

et al. 1999

Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…Many of the PRL family members have been shown to participate in the orchestration of maternal adaptations to pregnancy (Soares et al 1998, Linzer & Fisher 1999. Maternal target tissues include the ovary (Galosy & Talamantes 1995), uterus (Nelson et al 1995), vasculature (Jackson et al 1994), mammary glands (Thordarson et al 1986, Colosi et al 1988a, brain (Bridges et al 1996, Voogt et al 1996, pancreas (Brelje et al 1993), hematopoietic cells (Lin & Linzer 1999) and immune cells (Robertson et al 1982, Cohick et al 1996, Müller et al 1999.…”

Section: Introductionmentioning

confidence: 99%

Three novel paralogs of the rodent prolactin gene family

Dai

Wang²,

Liu³

et al. 2000

Journal of Endocrinology

View full text Add to dashboard Cite

The prolactin (PRL) family consists of a collection of genes expressed in the uterus, placenta and anterior pituitary. These cytokines/hormones participate in the control of maternal-fetal adaptations to pregnancy. In this report, we establish the presence of three new members of the PRL family. Novel expressed sequence tags (ESTs) with homology to PRL were isolated from embryonic and placental cDNA libraries. The cDNAs were sequenced and compared with those of other members of the PRL family. The three new cDNAs were assigned to the PRL family on the basis of sequence similarities and were referred to as PRL-like protein-J (PLP-J), PRL-like protein-K (PLP-K) and PRL-like protein-M (PLP-M). Both rat and mouse PLP-J cDNAs were identified. Rat PLP-J cDNA encodes for a predicted 211 amino acid protein containing a 29 amino acid signal peptide and two putative N-linked glycosylation sites, whereas the mouse PLP-J cDNA encodes for a 212 amino acid protein containing a 29 amino acid signal peptide with a single N-linked glycosylation site. Rat and mouse PLP-J proteins share approximately 79% and 70% nucleotide and amino acid sequence identity, respectively. A full-length rat PLP-K cDNA and a partial tentative mouse PLP-K cDNA were identified. The rat PLP-K cDNA encodes for a predicted 228 amino acid protein containing a 31 amino acid signal peptide and one putative N-linked glycosylation site; the mouse PLP-M cDNA encodes for a predicted 228 amino acid protein containing a 28 amino acid signal peptide and one putative N-linked glycosylation site. Genes for PLP-J, PLP-K and PLP-M are situated at the Prl family locus on mouse chromosome 13. PLP-J was exclusively expressed in decidual tissue from both the mouse and rat. PLP-K was expressed in trophoblast cells of the chorioallantoic placenta and showed an apparent species difference. In the mouse, virtually all trophoblast lineages expressed PLP-K, whereas in the rat, PLP-K expression was restricted to the labyrinthine trophoblast cells. Mouse PLP-M expression was restricted to the junctional zone of the chorioallantoic placenta. In summary, we have identified three new members of the rodent PRL gene family that are expressed in uterine and placental structures. Future experimentation is needed to determine the specific roles of each of these ligands in the biology of pregnancy.

show abstract

“…The uteroplacental prolactin (PRL) family of cytokines/hormones participates in the regulation of physiological mechanisms ensuring viviparity (Soares et al 1998). Individual members of the PRL family have been shown to possess classical PRL-like actions, implicating their participation in the control of maternal ovarian and mammary gland development and function (Thordarson et al 1986, Colosi et al 1988a, Galosy & Talamantes 1995, while other members possess nonclassical actions and may contribute to the establishment of vascular connectivity between maternal and fetal compartments (Jackson et al 1994, Linzer 1995, immune regulation (Robertson et al 1982, 1994, Cohick et al 1996, Dai et al 1996a, Müller et al 1999, and the control of hematopoiesis (Lin & Linzer 1999). …”

Section: Introductionmentioning

confidence: 99%

Identification of two new nonclassical members of the rat prolactin family

Sahgal¹,

Knipp²,

Liu³

et al. 2000

Journal of Molecular Endocrinology

View full text Add to dashboard Cite

The prolactin (PRL) family is comprised of a group of hormones/cytokines that are expressed in the anterior pituitary, uterus, and placenta. These proteins participate in the control of maternal and fetal adaptations to pregnancy. In this report, we have identified two new nonclassical members of the rat PRL family through a search of the National Center for Biotechnology Information dbEST database. The cDNAs were sequenced and their corresponding mRNAs characterized. Overall, the rat cDNAs showed considerable structural similarities with mouse proliferin-related protein (PLF-RP) and prolactin-like protein-F (PLP-F), consistent with their classification as rat homologs for PLF-RP and PLP-F. The expression of both cytokines/hormones was restricted to the placenta. The intraplacental sites of PLF-RP and PLP-F synthesis differed in the rat and the mouse. In the mouse, PLF-RP was expressed in the trophoblast giant cell layer of the midgestation chorioallantoic and choriovitelline placentas and, during later gestation, in the trophoblast giant cell and spongiotrophoblast layers within the junctional zone of the mouse chorioallantoic placenta. In contrast, in the rat, PLF-RP was first expressed in the primordium of the chorioallantoic placenta (ectoplacental cone region) and, later, exclusively within the labyrinth zone of the chorioallantoic placenta. In the mouse, PLP-F is an exclusive product of the spongiotrophoblast layer, whereas in the rat, trophoblast giant cells were found to be the major source of PLP-F, with a lesser contribution from spongiotrophoblast cells late in gestation. In summary, we have established the presence of PLF-RP and PLP-F in the rat.

show abstract

Lactogenic response of cultured mouse mammary epithelial cells to mouse placental lactogen

Cited by 46 publications

References 35 publications

Differential expression of the growth hormone receptor and growth hormone-binding protein in epithelia and stroma of the mouse mammary gland at various physiological stages

Differential expression of the growth hormone receptor and growth hormone-binding protein in epithelia and stroma of the mouse mammary gland at various physiological stages

Three novel paralogs of the rodent prolactin gene family

Identification of two new nonclassical members of the rat prolactin family

Contact Info

Product

Resources

About