Reduced number of intrinsic pulmonary nitrergic neurons in Fawn-Hooded rats as compared to control rat strains.
The Fawn-Hooded rat (FHR) strain reveals a congenital predisposition to primary (idiopathic) pulmonary hypertension (PPH), and can therefore be regarded as an animal model in which to study possible mechanisms underlying an inherited susceptibility to pulmonary hypertension. Pulmonary hypertension can be induced in FHRs after a short exposure to mild hypoxia, presumably because of an altered peripheral oxygen sensitivity. Given the presence of pulmonary nitrergic neurons in rat lungs, the observed link between airway hypoxia and the expression of pulmonary neuronal nitric oxide synthase (nNOS), and the fact that nNOS appears to be involved in peripheral chemoreceptor sensitivity, we examined the intrinsic pulmonary nitrergic innervation in the FHR. In the present study the number of intrapulmonary nitrergic nerve cell bodies, detected by NADPH diaphorase (NADPHd) histochemistry, was quantified in the FHR and three control rat strains. Compared to the control rat strains, the FHR lungs revealed a highly significantly lower number of intrinsic nitrergic neurons, while no apparent differences were found in the number of enteric nitrergic neurons in the esophagus. In conclusion, the possible links between neuronal NO, hypersensitivity to airway hypoxia, and the development of PPH clearly deserve further investigation.
Van Genechten
Jeroen
J
Laboratory of Cell Biology and Histology, Department of Biomedical Sciences, University of Antwerp (RUCA), Antwerp, Belgium.
Brouns
Inge
I
Scheuermann
Dietrich W
DW
Timmermans
Jean-Pierre
JP
Adriaensen
Dirk
D
D000818:Animals; D017776:Autonomic Pathways / Q000002:abnormalities* / Q000201:enzymology / Q000473:pathology; D002452:Cell Count; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000502:physiology; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006976:Hypertension, Pulmonary / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology; D007150:Immunohistochemistry; D008297:Male; D009252:NADPH Dehydrogenase / Q000378:metabolism; D026602:Nitrergic Neurons / Q000201:enzymology / Q000473:pathology*; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D011651:Pulmonary Artery / Q000002:abnormalities* / Q000294:innervation / Q000473:pathology; D051381:Rats; D011916:Rats, Inbred F344; D011922:Rats, Mutant Strains / Q000002:abnormalities*; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013045:Species Specificity; D014661:Vasoconstriction / Q000502:physiology
D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D009252:NADPH Dehydrogenase