Colipase and maximally activated pancreatic lipase in normal subjects and patients with steatorrhea.

Parallel Secretion of Pancreatic Phospholipase A2, Phospholipase A1, Lipase, and Colipase in Children with Exocrine Pancreatic Dysfunction

“…In a previous study, normal values of colipase secretion among a group of normal young adult controls were more than 6500 U·kg -1 ·h Ϫ1 , with an average value of 12,740 U·kg Ϫ1 ·h Ϫ1 (3). The values in the current study were consistent with values obtained previously in PS patients (2)(3)(4), noting that the one normal subject with a value of 5100 U·kg Ϫ1 ·h Ϫ1 was younger than previous normal controls. The patient with MCC had a lower output of colipase activity but comparable to one of the CF-PS patients (Table 1).…”

“…The results also emphasized the important role of colipase in vivo, as, in a group of patients with seemingly adequate lipase output above the threshold level, fat malabsorption occurred because of inadequate cosecretion of colipase. This confirmed in vitro observations that lipase in the presence of supramicellar concentrations of bile salts is only active if colipase is present and remains inactive in the absence of colipase (4,7,8).…”

“…Lipase and colipase concentrations were measured, and their rates of secretion were calculated as previously described (3,4). The titrimetric enzyme assays were carried out at 37°C with glycerol tributyrate as the lipid substrate.…”

“…To determine the relationship between residual pancreatic function and fat absorption, sensitive titrimetric assays were developed for lipase and the lipase cofactor colipase (4) and their secretion rates compared with fecal fat excretions in children with CF, Shwachman syndrome, or controls (3,5). These studies demonstrated that patients with normal fat absorption had a wide range of enzyme/coenzyme secretion from less than 5% up to within the normal control range; and the threshold for lipolytic failure was near 1% of average control colipase values, i.e.…”

Nutritional care in children with cystic fibrosis: are our patients becoming better?

“…These definitions are based on quantitative pancreatic stimulation tests with duodenal aspiration of pancreatic juice, and analysis of lipase and the lipase co-factor, colipase, in comparison with faecal fat excretion during 3-5-day fat balance studies. 34,35 Colipase determines the amount of lipase activity in the presence of bile acids, 34 and thus it was not unexpected that the amount of colipase secreted was a critical factor in these studies, as patients secreting over 1% of average normal colipase had normal fat absorption and o1% fat malabsorption, as per Figure 4. 35 Genotyping as per classes of CFTR mutations 36 of patients with PI and PS pancreatic phenotypes has revealed that PI patients have two type I, II or III mutations and PS patients at least one type IV or V mutation.…”