1、αίτια
διότι οι κύτταρα PP του παγκρέατος του παραγάγουν μεγάλη ποσότητα πολυπεπτίδων, προκαλώντας τις παθολογικές εκφράσεις που προκαλείται από την πολυπεπτίδα του παγκρέατος.
2、έκδοση μηχανισμού
1972Μετά τη διάκριση του PP από το Chance, Kimmel και Pollack, έχουν δημοσιευτεί μερικές αναφορές για την φυσιολογική του δράση, η PP αυξάνεται明显 μετά το γεύμα και μπορεί να διαρκέσει6~8h, the biological function and the physiological significance of increasing after meals are not yet clear, it may be to regulate the postprandial enzyme, so that the secretion of digestive juices does not become too excessive or too long, and plays a certain degree of 'braking' role. However, the physiological function of PP in humans is not well understood, and Greenberg et al. believe that PP in humans has the physiological function of inhibiting gallbladder contraction and promoting pancreatic juice secretion.
PPoma is mostly located in the head of the pancreas, less in the body and tail, and a few patients have tumor distribution in extrapancreatic organs. The tumor often has a complete capsule, and bleeding and necrosis or cystic change may be seen in the section; the tumor body is often large, and the diameter is often greater than5cm; tumors are often solitary. The disease is mostly malignant, with a small part being benign tumors or only PP cell hyperplasia. The common metastatic sites of malignant PPoma are the liver, but they can also metastasize to the lung, brain, and bone. By immunohistochemical methods, using a variety of gastrointestinal hormone antisera for examination, it can be seen that the content of PP is the highest, and other gastrointestinal hormones are negative or weakly positive. The determination of PP in tumor tissue shows that its content is extremely high, reaching196.5μg/g wet tissue, while other gastrointestinal hormones are very little or negative. Electron microscopy examination shows that the granular morphology of tumor cells is consistent with PP granules.