ISSN:
1432-0428
Keywords:
Experimental insulinoma
;
experimental nesidioblastoma
;
experimental islet cell tumor in rats
;
immunoreactive insulin content of experimental insulinomas
;
ultrastructure of experimental insulinomas
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Young male Holtzman rats were injected intravenously with 50 mg/kg of Streptozotocin, preceded and followed by a single intraperitoneal injection of 350 mg/kg of nicotinamide, according to the method of Rakieten et al. [16]. After 245 to 323 days, 27 pancreatic islet cell tumors measuring up to 0.6 cm were demonstrable in 20 of 41 rats so treated; they were solitary in 15 and multiple (two or three neoplasms each) in five animals. It was not possible to distinguish between tumor-bearing and tumor-free rats on the basis of periodic blood sugar determinations and serum insulin assays. Mean insulin concentration in grossly tumor-free pancreatic specimens was 0.661 units of insulin/g of wet tissue, but amounted to 5.385 units/g in specimens containing tumor. The islet cell tumors were rounded and well delineated. They were located in all parts of the pancreas. In general, their cells stained deeply with aldehyde-fuchsin. Ultra-structurally, most tumors consisted of well granulated B cells. A or D cells were not encountered while occasional EC cells were identified. Nucleoli were frequently prominent. Some necrotic B cells and others with few or unusually small secretory granules were present. Extravasated erythrocytes as well as hemosiderin deposits were seen in many tumors, and tumor cell particles were occasionally noted within the lumina of capillaries. Distant metastases were not demonstrable in this group of animals.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00421412
