bjectives : Aminopeptidase N and DAP-IV (dipeptidyl aminopeptidase IV) have been
established as membrane). Recent reports indicate that ACE (angiotensin converting enzyme),
carboxypeptidase P and several endopeptidases are found in BBM. Proline rich proteins such
as casein and collagen are importan dietary constituents. Prolyl peptide bonds are generally
resistant to the action of several peptidases. DAP-IV and ACE are known as prolyl bond
specific petidases enzyme in vivo is not known. The dietary regulation of intestinal enzymes
has been well established. The present study was designed to investigate the response of
intestinal ACE to the high proline diet (gelatin), and therefore evaluate the role as a digestive
enzyme.
Methods : Total 14 male Wistar rats were divided in 2 groups. Control group was
maintained on standard chow diet, and gelatin group was maintained on 20% gelatin gel 50
mg/rat/day and half of standard chow diet for 3 weeks. Mucosal homogenate and BBM were
prepared. The protein level and specific activites of ACE, aminopeptidase N, DAP-IV,
sucrase and alkaline phosphatase were measured in homogenate and BBM.
Results :
1) The specific activities of ACE and DAP-IV were significantly induced in mucosal
homogenates of proximal and middle intestines of gelatin group compared with those of
control (p<0.05) (Table 3,4).
2) The specific actives of aminopeptidase N, sucrases and alkaline phosphatase were not
induced in mucosal homogenate and BBM of gelatin group compared with those of control.
Conclusion : The specific activities of ACE and DAP-IV were significantly induced by
high proline diet. This result suggests that intestinal ACE may play a physiologic role in
protein digestion like DAP-IV.
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