Effect of exercise on the nasal transmucosal potential difference in patients with cystic fibrosis and normal subjects.

Abstract

CNP in cor pulmonale and heart failure than as a circulating hormone involved in cardiovascular homeostasis. Thus, measurement of plasma CNP levels and studies involving systemic infusions of CNP may have only a limited role in clarifying its physiological significance. Background-Normal subjects have a negative nasal transmucosal potential difference (TPD) at rest which becomes more negative with exercise. Patients with cystic fibrosis have a more negative resting nasal TPD than controls. The present study was designed to determine the effects of exercise on the TPD of patients with cystic fibrosis. Methods -Seven subjects with cystic fibrosis and seven control subjects had their usual TPD measured at rest, and during and after a 12 minute period on an exercise bicycle designed to produce a pulse rate of 80% of their maximum predicted value. Results -The normal subjects developed a more negative nasal TPD during exercise which returned towards normal at the completion ofthe rest period. The patients with cystic fibrosis had higher resting values which became less negative during exercise. At the end of the exercise period there was no difference between the two groups. At the end of the recovery period

Exercise reduces airway sodium ion reabsorption in cystic fibrosis but not in exercise asthma

“…Catecholamine-stimulated cAMP production might increase Na + channel activity even further [4], which might exaggerate the depletion of airway lining fluid caused by the defective CFTR. Results of nasal potential measurements of CF patients unanimously show decreases in nasal potential in the first ,20 min of exercise [9,21]. We confirm this result and show that the decrease was much larger in CF than in healthy individuals.…”

“…We confirm this result and show that the decrease was much larger in CF than in healthy individuals. The decrease in nasal potential during exercise of CF patients in our study was smaller than that observed by HEBESTREIT et al [9] but was in the range of changes found by ALSUWAIDAN et al [21] in the first 15-20 min of exercise. We have no explanation for this discrepancy.…”

“…Changes in nasal potential during submaximal exercise have been reported earlier [9,21]. In healthy individuals, ALSUWAIDAN et al [21] found a gradual increase in nasal potential in the first 15 min of exercise at an intensity of ,80% of the predicted maximal heart rate, which was followed by a slow return towards baseline.…”

“…In healthy individuals, ALSUWAIDAN et al [21] found a gradual increase in nasal potential in the first 15 min of exercise at an intensity of ,80% of the predicted maximal heart rate, which was followed by a slow return towards baseline. In contrast, HEBESTREIT et al [9], who exercised their individuals at 85% of the intensity at the ventilatory threshold, found a decrease in nasal potential and NP Damil .…”

“…HEBESTREIT et al [9] found a decreased nasal potential difference during submaximal exercise in healthy controls. Two studies have shown that exercise decreases the nasal potential difference in patients with CF [9,21], which seems to be due to inhibition of nasal epithelial Na + reabsorption [9]. Both studies used low intensity exercise, but dependency on exercise intensity is not known.…”