Basic FGF localization in rat carotid body: paracrine role in O2 -chemoreceptor survival

• Published in: Neuroreport Vol. 12; no. 15; p. 3287
• Main Authors: Paciga, M, Nurse, C A
• Format: Journal Article
• Language: English
• Published: England 29.10.2001
• Subjects: Animals; Animals, Newborn; Antibodies - pharmacology; Bromodeoxyuridine; Carotid Body - cytology; Carotid Body - drug effects; Carotid Body - metabolism; Cell Death - drug effects; Cell Death - physiology; Cell Division - drug effects; Cell Division - physiology; Cell Survival - drug effects; Cell Survival - physiology; Cells, Cultured - cytology; Cells, Cultured - drug effects; Cells, Cultured - metabolism; Fibroblast Growth Factors - antagonists & inhibitors; Fibroblast Growth Factors - metabolism; Fluorescent Antibody Technique; Hypoxia - metabolism; Hypoxia - physiopathology; Male; Oxygen - metabolism; Paracrine Communication - drug effects; Paracrine Communication - physiology; Rats; Rats, Wistar; Receptors, Fibroblast Growth Factor - metabolism; Tyrosine 3-Monooxygenase - metabolism
• ISSN: 0959-4965; 1473-558X
• DOI: 10.1097/00001756-200110290-00028

Exposure of perinatal rat carotid body (CB) O2-chemoreceptors to basic fibroblast growth factor (bFGF) or hypoxia in vitro increases mitotic activity. Using double-label immunofluorescence, we localized bFGF and its receptor (FGFR) to tyrosine hydroxylase-positive (TH+) chemoreceptors in vitro; bFGF immunoreactivity also localized to chemoreceptors in CB tissue sections. Mitotic activity, measured as percentage TH+ cells that took up bromodeoxyuridine, was relatively constant ( approximately 29%) in normoxic (20% O2) cultures grown with or without bFGF neutralizing antibody (nAb). However, the number of surviving chemoreceptors was significantly reduced in nAb-treated cultures. Under chronic hypoxia (6% O2), the presence of nAb significantly reduced chemoreceptor survival to approximately 70% of control, without affecting mitotic activity. Thus, autocrine/ paracrine actions of endogenous bFGF may help promote CB chemoreceptor survival.