title: Defective fluid secretion from submucosal glands of nasal turbinates from CFTR-/- and CFTR (ΔF508/ΔF508) pigs.
abstract: BACKGROUND
  Cystic fibrosis (CF), caused by reduced CFTR function, includes severe sinonasal disease which may predispose to lung disease. Newly developed CF pigs provide models to study the onset of CF pathophysiology. We asked if glands from pig nasal turbinates have secretory responses similar to those of tracheal glands and if CF nasal glands show reduced fluid secretion.
  
  
  RESULTS
  Unexpectedly, we found that nasal glands differed from tracheal glands in five ways, being smaller, more numerous (density per airway surface area), more sensitive to carbachol, more sensitive to forskolin, and nonresponsive to Substance P (a potent agonist for pig tracheal glands). Nasal gland fluid secretion from newborn piglets (12 CF and 12 controls) in response to agonists was measured using digital imaging of mucus bubbles formed under oil. Secretion rates were significantly reduced in all conditions tested. Fluid secretory rates (Controls vs. CF, in pl/min/gland) were as follows: 3 µM forskolin: 9.2±2.2 vs. 0.6±0.3; 1 µM carbachol: 143.5±35.5 vs. 52.2±10.3; 3 µM forskolin + 0.1 µM carbachol: 25.8±5.8 vs. CF 4.5±0.9. We also compared CF(ΔF508/ΔF508) with CFTR(-/-) piglets and found significantly greater forskolin-stimulated secretion rates in the ΔF508 vs. the null piglets (1.4±0.8, n = 4 vs. 0.2±0.1, n = 7). An unexpected age effect was also discovered: the ratio of secretion to 3 µM forskolin vs. 1 µM carbachol was ∼4 times greater in adult than in neonatal nasal glands.
  
  
  CONCLUSIONS
  These findings reveal differences between nasal and tracheal glands, show defective fluid secretion in nasal glands of CF pigs, reveal some spared function in the ΔF508 vs. null piglets, and show unexpected age-dependent differences. Reduced nasal gland fluid secretion may predispose to sinonasal and lung infections.
authors.affiliation: Cystic Fibrosis Research Laboratory, Psychology Department, Stanford University, Stanford, California, United States of America. hyungjuc@stanford.edu
authors.forename: Hyung-Ju
authors.initials: HJ
authors.lastname: Cho
authors.forename: Nam Soo
authors.initials: NS
authors.lastname: Joo
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Wine
mesh_terms: D000375:Aging / Q000187:drug effects / Q000473:pathology; D000818:Animals; D000831:Animals, Newborn; D001826:Body Fluids / Q000187:drug effects / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D003550:Cystic Fibrosis / Q000473:pathology; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000172:deficiency* / Q000378:metabolism; D004357:Drug Synergism; D005088:Exocrine Glands / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D009154:Mutation / Q000235:genetics; D009929:Organ Size / Q000187:drug effects; D013373:Substance P / Q000494:pharmacology; D034421:Sus scrofa / Q000254:growth & development; D014132:Trachea / Q000187:drug effects / Q000473:pathology; D014420:Turbinates / Q000187:drug effects / Q000473:pathology*
chemical_list: C093349:cystic fibrosis transmembrane conductance regulator delta F508; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D005576:Colforsin; D013373:Substance P; D002217:Carbachol