Sensitizing effects of chronic exposure and acute inhalation of ovalbumin aerosol on pulmonary C fibers in rats

Guangfan Zhang, Ruei Lung Lin, Michelle E. Wiggers, Lu Yuan Lee

Research output: Contribution to journalArticlepeer-review

25 Scopus citations

Abstract

The effect of ovalbumin (Ova) sensitization on pulmonary C-fiber sensitivity was investigated. Brown-Norway rats were sensitized by intraperitoneal injection of Ova followed by aerosolized Ova three times per week for 3 wk. Control rats received the vehicle. At the end of the third week, single-unit fiber activities (FA) of pulmonary C fibers were recorded in anesthetized, artificially ventilated rats. Our results showed the following: 1) Ova sensitization induced airway inflammation (infiltration of eosinophils and neutrophils) and airway hyperresponsiveness in rats; 2) baseline FA in sensitized rats was significantly higher than that in control ones; 3) similarly, the pulmonary C-fiber response to right atrial injection of capsaicin was markedly higher in sensitized rats, which were significantly amplified after the acute Ova inhalation challenge; and 4) similar patterns, but smaller magnitudes of the differences in C-fiber responses to adenosine and lung inflation, were also found between sensitized and control rats. In conclusion, Ova sensitization elevated the baseline FA and excitability of pulmonary C fibers, and the hypersensitivity was further potentiated after the acute Ova inhalation challenge in sensitized rats. Chronic allergic inflammatory reactions in the airway probably contributed to the sensitizing effect on these lung afferents.

Original languageEnglish
Pages (from-to)128-138
Number of pages11
JournalJournal of Applied Physiology
Volume105
Issue number1
DOIs
StatePublished - Jul 2008

Keywords

  • Airway hyperresponsiveness
  • Allergen
  • Asthma
  • Inflammatory mediators
  • Vagus

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Fingerprint

Dive into the research topics of 'Sensitizing effects of chronic exposure and acute inhalation of ovalbumin aerosol on pulmonary C fibers in rats'. Together they form a unique fingerprint.

Cite this