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Characterization of secretory responses in exocrine pancreas of genetically obese Zucker rats

  • Yoshiaki Habara
  • Akira Uehara
  • Yuichi Takasugi
  • Masayoshi Namiki
  • Tomio Kanno
Article

Summary

Secretory responses of the exocrine pancreas in the obese Zucker rat with an inherited genetic disorder were compared with those in lean control rats. Amylase concentration in pancreatic acinar cells of obese rats was reduced to 62% of the control value, whereas trypsinogen concentration was increased to 269%. The activity ratio of amylase to trypsinogen in the pancreatic acini of obese rats was about one-fourth of that in controls. The activity ratio of amylase to trypsinogen in pancreatic juice released by stimulation with varying concentrations of CCK8 or carbachol in the obese rats was also reduced to one-fourth of that in control rats. The concentration of the secretagogs inducing half-maximal secretory responses (EC50) in the obese rats was almost identical to that in the controls. The downward shift of the dose-response relation for these secretagogs in the acini of obese rats was analogous to that in streptozotocin-induced diabetic rats, cold-exposed rats, or lactating rats, as demonstrated previously. The present results may be explained by the changes in enzyme content and secretory responses found in pancreatic acini of obese Zucker rats, which would be attributable mainly to congenital disturbance in “insulo-acinar axis.”

Key Words

Pancreatic acinar cell cholecystokinin octapeptide hyperphagia insulin 

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Copyright information

© The Humana Press Inc 1991

Authors and Affiliations

  • Yoshiaki Habara
    • 1
  • Akira Uehara
    • 2
  • Yuichi Takasugi
    • 2
  • Masayoshi Namiki
    • 2
  • Tomio Kanno
    • 1
    • 3
  1. 1.Laboratory of Cellular Metabolism, Department of Molecular PhysiologyInstitute for Physiological SciencesOkazakiJapan
  2. 2.III Department of Internal MedicineAsahikawa Medical CollegeAsahikawaJapan
  3. 3.Department of PhysiologyFaculty of Veterinary Medicine, Hokkaido UniversitySapporoJapan

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