Evidence of a Direct Role for Growth Hormone (GH) in Mammary Gland Proliferation and Lactation
Autor: | Fred Sinowatz, R. L. Hughes, Michael J. Waters, D. T. Lincoln, El-Sayed El-Hifnawi |
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Rok vydání: | 1995 |
Předmět: |
medicine.medical_specialty
Receptor expression Mammary gland Biology Mammary Glands Animal Pregnancy Growth hormone-binding protein Cell surface receptor Internal medicine medicine Animals Lactation Rats Wistar Receptor General Veterinary Binding protein Antibodies Monoclonal Receptors Somatotropin General Medicine Immunohistochemistry Somatomedin Rats medicine.anatomical_structure Endocrinology Growth Hormone Female Rabbits |
Zdroj: | Anatomia, Histologia, Embryologia: Journal of Veterinary Medicine Series C. 24:107-115 |
ISSN: | 1439-0264 0340-2096 |
Popis: | A panel of monoclonal antibodies to the growth hormone (GH) receptor/binding protein was used to demonstrate the existence and detail the expression of GH receptors in ductal and alveolar epithelial cells from rat and rabbit mammary glands by immunohistochemistry. Intense immunoreactivity was present in membrane, cytoplasm and some nuclei of epithelial cells during proliferation and lactation. Receptor expression decreased during weaning and was absent or weak in regressive mammary glands. Immunoreactivity was weak in ductal epithelial cells from virgin adult animals. Pronounced expression of GH receptor/binding protein was observed with two monoclonal antibodies and lesser reactivity was seen with others, paralleling their affinities for the receptor. The cytoplasmic presence of this putatively plasma membrane located GH receptor is accounted for by the existence of a soluble form on the GH receptor, namely the growth hormone binding protein derived from the membrane receptor by cleavage. Primary localization of the receptor in proliferating and lactating epithelial cells suggests that the rat and rabbit mammary gland is a GH target tissue. This finding is in contradiction to both classical GH action and the somatomedin hypothesis and challenges the widely held view that GH has no direct influence on mammary growth and function. Copyright |
Databáze: | OpenAIRE |
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