Table 1 . Serum Quinidine Concentrations In Patients with Normal and impaired Renal Function

CLINICAL CHEMISTRY, Vol. 28, No. 4, 1982 723 tients who had undergone vagotomy and pyloroplastybutdidnot have dumping syndrome (8). However, only baseline and maximum values were reported, and the authors did not comment regarding the temporal changes inthese hormones asrelatedtothepresenceorabsenceof symptoms. The results we report indicate that, in thispatient,theearlysymptoms ofthe dumping syndrome did not correlate with changes in plasma catecholamines, but the late reactive hypoglycemia and associated symptoms were associated with a marked increase in these compounds. It appears, therefore, that the symptoms of earlydumpingsyndrome are not primarily catecholamine mediated. Improvement in symptoms of the early and late phases in patients treated with 10 mg of oral propranolol 30 mm before an OGTT has been reported (9); unfortunately, concentrations of catecholamine were not reported in that study. In view of the catecholamine results determined in the present study, propranolol may be exerting a beneficial effect by some means other than blockade of excess catecholamine action.