Ruminants express a prolactin receptor of Mr 33 000—36 000 in the mammary gland throughout pregnancy and lactation

1993 ◽  
Vol 139 (1) ◽  
pp. 37-49 ◽  
Author(s):  
J. J. Smith ◽  
A. V. Capuco ◽  
I. H. Mather ◽  
B. K. Vonderhaar
Keyword(s):  
Mammary Gland ◽  
Developmental Stages ◽  
Developmental Regulation ◽  
Prolactin Receptor ◽  
Binding Activity ◽  
Receptor Type ◽  
Mammary Tissue ◽  
Cross Linking ◽  
Developmental Variation ◽  
Pregnancy And Lactation

ABSTRACT Developmental variation in the expression of the prolactin receptor in the ruminant mammary gland was investigated. Affinity chromatography revealed that bovine prolactin and human GH each bound to the same mammary gland proteins, yielding fractions enriched in binding activity and a protein of Mr 36 000, assumed to be a bovine prolactin receptor. Affinity cross-linking of 125I-labelled human GH to mammary microsomes confirmed that the Mr 36 000 protein was a bovine prolactin receptor. Binding assays of receptors in microsomes from the mammary tissue of cows and ewes at various stages of the lactational/reproductive cycle indicated developmental regulation of receptor concentration, but not receptor type, as no other bovine prolactin receptor type was detected by affinity cross-linking. These results suggest that differences in the response to prolactin in the mammary gland at various developmental stages in ruminants are not due to the expression of different forms of the prolactin receptor, and the lack of a prolactin effect on established lactation in ruminants is not due to the absence of the Mr 36 000 form of the prolactin receptor. Journal of Endocrinology (1993) 139, 37–49

XXIV.—The Innervation of the Human Quiescent Nipple, with Notes on Pigmentation, Erection, and Hyperneury

1949 ◽  
Vol 61 (3) ◽  
pp. 699-717 ◽  
Author(s):  
E. P. Cathcart ◽  
F. W. Gairns ◽  
H. S. D. Garven
Keyword(s):  
Mammary Gland ◽  
Considerable Change ◽  
The Other ◽  
Mammary Tissue ◽  
Histological Structure ◽  
Nerve Fibres ◽  
Histological Studies ◽  
Pregnancy And Lactation ◽  
To Receive ◽  
Stimulation Of

It has been known from antiquity that involution of the uterus is aided by putting the child to the breast, and the work of Moir (1933) has demonstrated conclusively that suckling brings about waves of contraction of the puerperal uterus. Since suckling must necessarily involve stimulation of the nipple, it seemed of interest to know what sensory apparatus is present in the nipple to receive these stimuli. While histological studies of the mammary gland itself have been numerous, only slight attention has been paid to the histological structure of the areola and the nipple.It must be appreciated from the outset that the present study is devoted to the innervation of the nipple in the quiescent breast. There may be considerable change during pregnancy and lactation, not only in the size of the organ and its epithelium but also in the other structures. It has been shown that there is an increase in the number of nerve-fibres in the actively secreting mammary tissue, and it is possible that there is an increase in the nerve-structures of the nipple also. The richness of the innervation in the quiescent nipple certainly makes a further study of these nerve-structures during pregnancy and lactation of great interest.

Nuclear targeting of stanniocalcin to mammary gland alveolar cells during pregnancy and lactation

2005 ◽  
Vol 289 (4) ◽  
pp. E634-E642 ◽  
Author(s):  
Craig P. Hasilo ◽  
Christopher R. McCudden ◽  
J. Ryan J. Gillespie ◽  
Kathi A. James ◽  
Edward R. Hirvi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Mammary Gland ◽  
Molecular Mass ◽  
Chemical Reduction ◽  
Mammary Tissue ◽  
Nuclear Targeting ◽  
Alveolar Cells ◽  
Hormone Production ◽  
Pregnant Rats ◽  
Pregnancy And Lactation

In most mammalian tissues, the stanniocalcin-1 gene (STC-1) produces a 50-kDa polypeptide hormone known as STC50. Within the ovaries, however, the STC-1 gene generates three higher-molecular-mass variants known as big STC. Big STC is targeted locally to corpus luteal cells to block progesterone release. During pregnancy and lactation, however, ovarian big STC production increases markedly, and the hormone is released into the serum. During lactation, this increase in hormone production is dependent on a suckling stimulus, suggesting that ovarian big STC may have regulatory effects on the lactating mammary gland. In this report, we have addressed this possibility. Our results revealed that virgin mammary tissue contained large numbers of membrane- and mitochondrial-associated STC receptors. However, as pregnancy progressed into lactation, there was a decline in receptor densities on both organelles and a corresponding rise in nuclear receptor density, most of which were on milk-producing, alveolar cells. This was accompanied by nuclear sequestration of the ligand. Sequestered STC resolved as one ∼135-kDa band in the native state and therefore had the appearance of a big STC variant. However, chemical reduction collapsed this one band into six closely spaced, lower-molecular-mass species (28–41 kDa). Mammary gland STC production also underwent a dramatic shift during pregnancy and lactation. High levels of STC gene expression were observed in mammary tissue from virgin and pregnant rats. However, gene expression then fell to nearly undetectable levels during lactation, coinciding with the rise in nuclear targeting. These findings have thus shown that the mammary glands are indeed targeted by STC, even in the virgin state. They have further shown that there are marked changes in this targeting pathway during pregnancy and lactation, accompanied by a switch in ligand source (endogenous to exogenous). They also represent the first example of nuclear targeting by STC.

scholarly journals Developmental regulation of Bcl-2 family protein expression in the involuting mammary gland

1999 ◽  
Vol 112 (11) ◽  
pp. 1771-1783 ◽  
Author(s):  
A.D. Metcalfe ◽  
A. Gilmore ◽  
T. Klinowska ◽  
J. Oliver ◽  
A.J. Valentijn ◽  
...  
Keyword(s):  
Cell Death ◽  
Mammary Gland ◽  
Epithelial Cells ◽  
De Novo ◽  
Mammary Epithelial Cells ◽  
Expression Profiles ◽  
Mammary Epithelial ◽  
Mammary Tissue ◽  
Pregnancy And Lactation

Epithelial cells within the mammary gland undergo developmental programmes of proliferation and apoptosis during the pregnancy cycle. After weaning, secretory epithelial cells are removed by apoptosis. To determine whether members of the Bcl-2 gene family could be involved in regulating this process, we have examined whether changes in their expression occur during this developmental apoptotic program in vivo. Bax and Bcl-x were evenly expressed throughout development. However, expression of Bak and Bad was increased during late pregnancy and lactation, and the proteins were present during the time of maximal apoptotic involution. Thereafter, their levels declined. In contrast, Bcl-w was expressed in pregnancy and lactation but was downregulated at the onset of apoptosis. Bcl-2 was not detected in lactating or early involuting mammary gland. Thus, the pro-apoptotic proteins Bax, Bak and Bad, as well as the death-suppressors Bcl-x, Bcl-2 and Bcl-w, are synthesised in mouse mammary gland, and dynamic changes in the expression profiles of these proteins occurs during development. To determine if changes in Bak and Bcl-w expression could regulate mammary apoptosis, their effect on cultured mouse mammary epithelial cells was examined in transient transfection assays. Enforced expression of Bak induced rapid mammary apoptosis, which could be suppressed by coexpression of Bcl-w. In extracts of mammary tissue in vivo, Bak heterodimerized with Bcl-x whereas Bax associated with Bcl-w, but Bak/Bcl-w heterodimers were not detected. Thus, Bak and Bcl-w may regulate cell death through independent pathways. These results support a model in which mammary epithelial cells are primed for apoptosis during the transition from pregnancy to lactation by de novo expression of the death effectors Bak and Bad. It is suggested that these proteins are prevented from triggering apoptosis by anti-apoptotic Bcl-2 family proteins until involution, when the levels of Bcl-w decline. Our study provides evidence that regulated changes in the expression of cell death genes may contribute to the developmental control of mammary apoptosis.

MAMMARY GLAND PROLACTIN RECEPTOR AND PITUITARY PROLACTIN SECRETION IN LACTATING MICE WITH DIFFERENT LACTATIONAL PERFORMANCE

1978 ◽  
Vol 88 (1) ◽  
pp. 94-98 ◽  
Author(s):  
Hiroshi Nagasawa ◽  
Reiko Yanai
Keyword(s):  
Mammary Gland ◽  
Prolactin Receptor ◽  
Correlation Coefficients ◽  
Binding Activity ◽  
Prolactin Secretion ◽  
Mammary Tumour ◽  
Receptor Sites ◽  
Lactational Performance ◽  
Pituitary Prolactin

ABSTRACT SHN female mice, a high mammary tumour strain, are superior to SLN, a low mammary tumour strain, in lactational performance. Mammary gland prolactin receptor and pituitary prolactin secretion during lactation were compared between these strains. The binding activity, the number of receptor sites per mg tissue and the association constant were measured by the in vitro incubation of mammary gland slices with 125I-labelled bovine prolactin, and the pituitary and plasma levels of prolactin were assayed by homologous radioimmunoassay. There was only a slight difference between strains in any of the parameters for prolactin receptor and for prolactin secretion on either day 4 or day 9 of the first lactation. Almost all the correlation coefficients between each parameter for prolactin receptor and the pituitary or plasma level of prolactin were not statistically significant. These findings suggest that any parameter for prolactin examined in this study is not always directly indicative of lactational performance and further show that the individual variation in the pituitary prolactin secretion during lactation is not so great as to alter the prolactin receptor.

scholarly journals Primary mammary organoid model of lactation and involution

2019 ◽  
Author(s):  
Jakub Sumbal ◽  
Aurelie Chiche ◽  
Elsa Charifou ◽  
Zuzana Koledova ◽  
Han Li
Keyword(s):  
Breast Cancer ◽  
Mammary Gland ◽  
Developmental Stages ◽  
System Modeling ◽  
Three Dimensional ◽  
Mammary Epithelium ◽  
Branching Morphogenesis ◽  
Pregnancy And Lactation ◽  
Key Aspects ◽  
Gland Development

AbstractMammary gland development occurs mainly after birth and is composed of three successive stages: puberty, pregnancy and lactation, and involution. These developmental stages are associated with major tissue remodeling, including extensive changes in mammary epithelium as well as surrounding stroma. Three-dimensional (3D) mammary organoid culture has become an important tool in mammary gland biology and enabled invaluable discoveries on pubertal mammary branching morphogenesis and breast cancer. However, a suitable 3D organoid model recapitulating key aspects of lactation and involution has been missing. Here, we describe a robust and straightforward mouse mammary organoid system modeling lactation and involution-like process, which can be applied to study mechanisms of physiological mammary gland lactation and involution as well as pregnancy-associated breast cancer.

Production of parathyroid hormone-related protein by the rat mammary gland in pregnancy and lactation

1992 ◽  
Vol 263 (6) ◽  
pp. E1077-E1085 ◽  
Author(s):  
M. Rakopoulos ◽  
S. J. Vargas ◽  
M. T. Gillespie ◽  
P. W. Ho ◽  
H. Diefenbach-Jagger ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Parathyroid Hormone ◽  
Mammary Tissue ◽  
Secretory Cells ◽  
Related Protein ◽  
Sprague Dawley ◽  
Parathyroid Hormone Related Protein ◽  
Pregnancy And Lactation ◽  
Rat Mammary Gland ◽  
In Pregnancy

Production of parathyroid hormone-related protein by the rat mammary gland in pregnancy and lactation. Am. J. Physiol. 263 (Endocrinol. Metab. 26): E1077-E1085, 1992.--Production of parathyroid hormone-related protein (PTHrP) by the mammary gland of Sprague-Dawley rats has been examined using immunohistochemistry and in situ hybridization to detect PTHrP and PTHrP mRNA, respectively. PTHrP and PTHrP mRNA could be demonstrated in nests of epithelial cells of the developing mammary gland at day 14 of pregnancy and in the epithelial secretory cells lining the alveoli during the latter stages of pregnancy and during lactation. A specific radioimmunoassay was also used to measure the concentration of PTHrP secreted in the milk throughout lactation. The concentration of PTHrP in milk was relatively low initially but increased during the latter stages of lactation, whereas calcium concentrations remained virtually constant throughout lactation. No correlation was found between the concentrations of calcium and PTHrP in rat milk. These results show that PTHrP is present in rat milk and also in mammary tissue before parturition, and therefore it may assist in the development of the mammary gland during pregnancy.

scholarly journals Transcript abundances of the prolactin receptor, the leptin receptor and their major suppressor in the sheep mammary gland during pregnancy and lactation

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Malgorzata Szczesna ◽  
Katarzyna Kirsz ◽  
Michal Nowakowski ◽  
Dorota A. Zieba
Keyword(s):  
Mammary Gland ◽  
Leptin Receptor ◽  
Prolactin Receptor ◽  
Signal Transduction Pathway ◽  
Late Pregnancy ◽  
Transcript Level ◽  
Transcript Abundance ◽  
Cytokine Signaling ◽  
Pregnancy And Lactation ◽  
Plasma Prl

AbstractThis study aimed to expand the knowledge of the interactions between prolactin (PRL) and leptin in the ovine mammary gland during pregnancy and lactation; we examined the mRNA expression of prolactin receptor (PRLR), the long form of the leptin receptor (LRb) and suppressor of cytokine signaling (SOCS)-3 in mammary gland biopsies collected on days 60, 90 and 120 of pregnancy and on days 30, 60 and 90 of lactation (n = 6 for each time point), along with the plasma PRL and leptin concentrations. The PRL concentrations were stable throughout pregnancy and increased during lactation. The plasma leptin concentrations were comparable among nonpregnant, early-pregnant, late-pregnant and lactating ewes, but this metric peaked during mid-pregnancy. Expression of PRLR and SOCS-3 in the mammary gland fluctuated during the transition from pregnancy to lactation, and differences in LRb expression occurred during the late stages of lactation. The LRb transcript abundance was approximately 31 times higher in ewes on day 60 of lactation than in early-lactating ewes. Expression of SOCS-3 mRNA in biopsies gradually decreased over the course of pregnancy and reached a minimum value during late pregnancy. After lambing, the transcript level of SOCS-3 increased and peaked on day 60 of lactation. During pregnancy, the plasma PRL concentration positively correlated with the abundances of PRLR (r = 0.971, P < 0.01) and SOCS-3 (r = 0.818, P < 0.05). Positive correlations were also observed between the transcript abundances of SOCS-3 and LRb (r = 0.854, P < 0.05). The variations observed in the plasma PRL and leptin concentrations and the changes in expression of key leptin and PRL signal transduction pathway components, such as PRLR, LRb and SOCS-3, indicate that the efficacies of both hormone actions are modulated in a multilevel manner throughout pregnancy and lactation. These interactions may regulate the ability of the mammary gland to respond to current energy requirements and challenges, thus affecting milk yield and lactation duration.

Production of parathyroid hormone-related protein by the rat mammary gland in pregnancy and lactation

2006 ◽  
Vol 263 (6) ◽  
pp. E1077-E1085 ◽  
Author(s):  
M. Rakopoulos ◽  
S. J. Vargas ◽  
M. T. Gillespie ◽  
P. W. Ho ◽  
H. Diefenbach-Jagger ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Parathyroid Hormone ◽  
Mammary Tissue ◽  
Secretory Cells ◽  
Related Protein ◽  
Sprague Dawley ◽  
Parathyroid Hormone Related Protein ◽  
Pregnancy And Lactation ◽  
Rat Mammary Gland ◽  
In Pregnancy

Production of parathyroid hormone-related protein by the rat mammary gland in pregnancy and lactation. Am. J. Physiol. 263 (Endocrinol. Metab. 26): E1077-E1085, 1992.--Production of parathyroid hormone-related protein (PTHrP) by the mammary gland of Sprague-Dawley rats has been examined using immunohistochemistry and in situ hybridization to detect PTHrP and PTHrP mRNA, respectively. PTHrP and PTHrP mRNA could be demonstrated in nests of epithelial cells of the developing mammary gland at day 14 of pregnancy and in the epithelial secretory cells lining the alveoli during the latter stages of pregnancy and during lactation. A specific radioimmunoassay was also used to measure the concentration of PTHrP secreted in the milk throughout lactation. The concentration of PTHrP in milk was relatively low initially but increased during the latter stages of lactation, whereas calcium concentrations remained virtually constant throughout lactation. No correlation was found between the concentrations of calcium and PTHrP in rat milk. These results show that PTHrP is present in rat milk and also in mammary tissue before parturition, and therefore it may assist in the development of the mammary gland during pregnancy.

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