Insulin and glucagon response to arginine infusion in cystic fibrosis.

The glucagon and insulin responses to intravenous arginine were studied in 17 
children with cystic fibrosis and in 9 control children. It was 
found that the overall secretion of insulin was diminished; however, four 
of the CF children did have a normal output. The glucagon 
responses did not parallel those of insulin. The glucagon output varied 
in the CF children--seven had normal, four excessively high and six 
low output. Three of the four children with extremely high output 
had more severe disease and were below the third centile on 
the weight chart. These four had a fasting hypoglycaemia and also 
a very low glucose and insulin response. We have confirmed diminished 
insulin secretion in cystic fibrosis, but diminished glucagon secretion was only 
noted when some insulin secretion was preserved. The high levels of 
glucagon seen in the most insulin deficient subjects may be derived 
from extrapancreatic sources, or may be associated with 'stress' reaction in 
these patients who also had most severe pulmonary involvement. The data 
would be consistent with diminished glucagon and insulin secretion from the 
pancreas but as the disease progresses an excessive secretion of extra 
pancreatic glucagon results. 