Bombesin-like peptide receptor gene expression, regulation, and function in fetal murine lung.

Published

Journal Article

Bombesin-peptide (BLP) immunoreactivity occurs at high levels in fetal lung. Previous studies showed that bombesin promotes fetal lung development. To test the hypothesis that such effects are mediated by known mammalian bombesin receptors [gastrin-releasing peptide (GRP)/bombesin-preferring receptor (GRPR), neuromedin B (NMB) receptor (NMBR), and the orphan bombesin receptor subtype-3 (BRS-3)], we analyzed the ontogeny of GRPR, NMBR, and BRS-3 gene expression in mouse lung. We examined the regulation of these three genes by dexamethasone and bombesin, which modulate lung development. Using incorporation of [3H]thymidine and [3H]choline, we then assessed whether GRP, NMB, and Leu8-phyllolitorin modulate lung growth and maturation in fetal lung explants. GRPR gene expression was detected predominantly in utero, whereas NMBR and BRS-3 genes were expressed from embryonic days 13-16 and on multiple postnatal days. All three mRNAs are present in airway epithelium and mesenchymal cells but occur in different relative patterns. These genes were regulated differently. Dexamethasone and bombesin increased GRPR mRNA, bombesin downregulated NMBR, and neither agent affected BRS-3. GRP increased incorporation of [3H]thymidine and [3H]choline in explants, whereas NMB induced cell proliferation and Leu8-phyllolitorin yielded variable results. Cumulative data suggest the involvement of multiple BLP receptors, including novel molecules, and argue against simple functional redundancy within this gene family during lung development.

Full Text

Duke Authors

Cited Authors

  • Shan, L; Emanuel, RL; Dewald, D; Torday, JS; Asokanathan, N; Wada, K; Wada, E; Sunday, ME

Published Date

  • January 2004

Published In

Volume / Issue

  • 286 / 1

Start / End Page

  • L165 - L173

PubMed ID

  • 12959933

Pubmed Central ID

  • 12959933

International Standard Serial Number (ISSN)

  • 1040-0605

Digital Object Identifier (DOI)

  • 10.1152/ajplung.00436.2002

Language

  • eng

Conference Location

  • United States