comparative study of the ultrastructure of submandibular, parotid and exocrine pancreas in diabetes and fasting

To comparatively analyze the ultrastructural changes in the submandibular and parotid glands and in the exocrine pancreas following diabetes induced by Streptozotocin exposure and the effects of fasting and insulin treatment on these alterations. For experimental procedure, we included 48 Sprague-Dawley type rats in July 2001-March 2002 at Gazi University, Turkey. We divided the rats into 8 groups following the infusion of Streptozotocin. While the degeneration manifested itself as accumulation of secretions within the mucous cells in the submandibular gland, lipid droplets were absent, being replaced by vacuolar structures. The parotid gland and exocrine pancreas, having similar properties, were affected similarly. Diabetes-induced loss of granules was observed in the serous cells in both glands. There was diffuse lipid accumulation within these cells. Regarding granule content, we observed the most prominent degenerative changes in the parotid gland. While cellular loss was observed in neither the submandibular, nor the parotid gland, we noted presence of apoptotic cells was noted in the pancreas. State of fasting was found to cause alterations within the glands indicating increased activity. While insulin treatment was seen to restore the structure to normal in general in both of the 3 glands. This study demonstrated that both of the 3 glands are affected by diabetes and concomitant fasting, and this effect manifests itself via the granule content

Effects of Aspartame on the Exocrine Pancreas of Rat Fetuses / Efectos del Aspartame en el Páncreas Exocrino de Fetos de Ratas

The present study evaluated the effects of the sweetener aspartame on the fetal pancreas, through a morphometric study, with the objective of studying the exocrine pancreas at the end of gestational development. For this we utilized two treated groups, one with a solution of aspartame at ambient temperature and the other with an aspartame solution heated to 40C, and two groups treated with water ad libitum, at ambient temperature and heated to 40C, respectively. On the final day of gestation the fetuses were removed and the pancreas was collected for microscopic analysis. The morphometric study demonstrated alteration in eight out of the eleven parameters studied in the group treated with the heated solution and one parameter altered in the group treated with solution at ambient temperature.

El presente estudio evalúa los efectos del endulzante aspartame en el páncreas fetal de rata, a través del estudio morfométrico, con el objetivo de conocer el páncreas exocrino al final del desarrollo gestacional. Fueron utilizados dos grupos tratados, uno con una solución de aspartame a temperatura ambiente y otro con una solución de aspartame calentada a 40C, y dos grupos tratados con agua ad libitum, a temperatura ambiente y calentada a 40 C, respectivamente. En el último día de gestación los fetos fueron removidos y el páncreas fue extraído para el análisis microscópico. El estudio morfométrico demostró alteraciones en ocho de los once parámetros estudiados en el grupo tratado con solución de aspartame calentada y un parámetro alterado en el grupo tratado con solución a temperatura ambiente.

Morphological Study of the Liver in the Teleost Oreochromis niloticus / Estudio Morfológico del Hígado en el Teleósteo Oreochromis niloticus

Liver samples of Oreochromis niloticus cultivated in floating net cages were fixed for histological and ultrastructural studies with the objective of describing the hepatic parenchymal structure and the intrahepatic exocrine pancreatic tissue. Anatomically, the liver showed only two hepatic lobes. Histological analysis demonstrated that the hepatocytes were spread out as anastomotic cords, arranged in two cellular layers and surrounded by sinusoids. The intrahepatic exocrine pancreatic tissue exhibited an acinar arrangement and was diffused in the hepatic parenchyma. Structural analysis showed that the hepatocytes had a rounded nucleus and a rough endoplasmic reticulum with a parallel disposition to the nuclear membrane. The exocrine pancreatic cells showed secretion granules at the apical portion and the rough endoplasmic reticulum was concentrically distributed.

Con el objetivo de describir la estructura del parénquima hepático y del páncreas exocrino intrahepático del Oreochromis niloticus, fueron fijados para estudios histológicos y ultraestructurales fragmentos de hígado de peces cultivados en jaulas flotantes. Se evidenciaron sólo 2 lóbubos hepáticos. El análisis histológico demostró que los hepatocitos se encontraban organizados en forma de cordones anastomosados, dispuestos en dos capas celulares y cercados por sinusoides. El tejido pancreático exocrino intrahepático se encontró difuso en el parénquima hepático y se destacó por su organización acinar. El análisis ultraestructural demostró que los hepatocitos presentaban núcleos redondos y el retículo endoplasmático rugoso estaba dispuesto paralelamente a la membrana nuclear. Las células pancreáticas exocrinas presentaban gránulos de secreción localizados en la porción apical y el retículo endoplasmático rugoso estaba organizado de manera concéntrica.