Abstract

The present study was undertaken: 1) to localize and characterize atrial natriuretic peptide (ANP) receptors in the rat mammary gland; and 2) to elucidate ANP-induced cellular formation of cyclic GMP (cGMP) and alterations in alveolar morphology during both early and late lactation. Receptor autoradiography, employing rat-specific [(125)1] ANP as radioligand, demonstrated binding sites in the secretory tissue and larger blood vessels of the mammary gland. Binding of [I-125]rANP to membrane fractions was completely displaced by unlabeled ANP and brain natriuretic peptide. C-type natriuretic peptide and cANP((4-23)) revealed limited competition with radiolabeled ANP only during early lactation, indicating a more heterogenous receptor population at that time. Systemically administered ANP induced cGMP formation in the alveolar epithelium, as shown with immunohistochemistry, and increased mammary tissue cGMP concentrations in vivo throughout the lactation period. Image analysis revealed enlargement of alveolar (but not epithelial) cell area after ANP stimulation in late lactation, suggesting altered alveolar filling or myoepithelial cell relaxation. These results indicate that ANP induces biological effects in the rat mammary gland through specific ANP-A receptor interaction with subsequent intracellular cGMP formation. ANP may therefore play a regulatory role in the control of mammary gland blood supply and secretory function

Published in

Endocrinology
1998, Volume: 139, number: 5, pages: 2615-2621
Publisher: ENDOCRINE SOC

SLU Authors

• Cvek, Katarina

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

• Ridderstråle, Yvonne

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Veterinary Science
Animal and Dairy Science


Publication identifier

DOI: https://doi.org/10.1210/en.139.5.2615

Permanent link to this page (URI)

https://res.slu.se/id/publ/24215