A recent study reports that patients with previous
acute pancreatitis commonly have an abnormal clearance of serum
triglycerides after an oral fat load. This observation supports the hypothesis that patients with previous
acute pancreatitis and normal fasting serum
triglyceride levels may have a preexistent abnormality in the metabolism of
chylomicrons. To test this hypothesis, the catabolism of
chylomicrons and their remnants was studied in a series of 7 patients who had sustained an attack of
pancreatitis (2,
gallstone related; 2, alcohol ingestion; 1,
hydatid cyst; and 3, no associated pathological condition) at least 18 mo earlier. All the patients had previously had abnormal oral-fat tolerance test results. These patients were compared with a series of 6 healthy volunteers.
Chylomicrons were endogenously labeled with an oral dose of
retinyl palmitate, and their plasma elimination half-life was calculated. The
retinyl palmitate absorption rate constants were similar in control and
pancreatitis patients. The
chylomicron t1/2 were 2.3 +/- 0.8 (SD) h and 3.9 +/- 1.8 h in the control and
pancreatitis groups, respectively (p = 0.07). The
chylomicron remnant t1/2 was 2.7 +/- 1.1 h in the control group and 5.2 +/- 2.4 h in the
pancreatitis group (p less than 0.05). This study supports the hypothesis that subjects with previous
acute pancreatitis may have an abnormality in the catabolism of
chylomicron particles. This abnormality may represent a preexistent genetic condition expressed in either the
apoprotein composition of
chylomicrons or in the hepatic
apolipoprotein E-receptor activity.