Electrolytes and norepinephrine levels in blood of patients with cystic fibrosis.

Young adults with cystic fibrosis in good to excellent condition have reduced 
plasma sodium and chloride and elevated plasma potassium compared to a 
group of healthy young adult control subjects. Blood pressure was also 
lower in the patients with cystic fibrosis. However, plasma norepinephrine and 
dopamine-beta-hydroxylase and their response to standing and isometric hand grip were 
normal in the cystic fibrosis patients. 