Tavuklarda pankreasın yapısal ve histokimyasal özellikleri alloxan verilmiş tavuklarda endokrin pankreasta görülen değişiklikler üzerinde araştırmalar
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Date
1988
Authors
Yakışık, Mine
Journal Title
Journal ISSN
Volume Title
Publisher
Uludağ Üniversitesi
Abstract
Çalışma erişkin tavuklarla yapıldı. Normal yaşam koşullarında barındırılan tavukların pankreaslarının yapısal özellikleri ışık mikroskopik düzeyde histoşimik metodlar kullanılarak incelendi. Ekzokrln pankreasın, apikal yarımları zymogen grandilerle dolu, pyramidal hücrelerden oluşana sinüsleri içerdiği gözlendi. Asinuslar arasında.duvarları tek katlı yassı epitelle döşeli initial kanallara çoğunlukla rastlandı. Gümüş impregnasyonu metodu ile yapılan preparetlarda sinirsel kayırılmanln nem ekzokrin pankreas hücrelerinde hem de endokrin pankreası oluşturan adacık hücrelerinde görüldüğü tesbit edildi. Çalışmanın ikinci 'bölümünde tavuklara % 5'lik alloxan ( tetrahydrat) 250 mg/kg dozunda verilerek, hayvanların kan şekeri düzeylerinde ve pankreaslarında meydana gelen değişiklikler gözlendi. Tavuklarda alloxan uygulamasından önce 180-260 mg/100 mi gibi fizyolojik sınırlar içinde hesaplanan kan şekeri düzeyinin, uygulamadan 1 saat sonra 315.7 mg/100 ml seviyesine yükseldiği tesbit edildi. Aynı hayvanlardan değişik zaman dilimlerinde alınarak hazırlanan ve Gomori' nin Chrome alum haematoxylin-phloxine tekniği ile boyanan pankreas preparatlarında, alloxan uygulamasından 1 saat sonra asiner hücrelerin zymogen granüllerini kaybetmiş oldukları görüldü. Endokrin adacıklardaki beta hücrelerinde ise, degranülasyon, çekirdeklerde piknoz ve karyolizis tesbit edildi. Beta hücrelerinde görülen dejenerasyon alloxan uygulamasının 48 saat sonrasına kadar artarak devam etti. Alloxan uygulamasından 5 saat sonra dejenere hücrelerden oluşan adacıklar çevresindeki asiner hücrelerde differensiasyon gözlendi. Bundan sonraki zaman dilimlerinde differensiye olan asiner hücrelerde yuvarlaklaşma ve sitoplazmalarında bazofilik granüllerin toplanmaya başlaması göze çarptı. Alloxan uygulamasından 48 saat sonra deney hayvanlarında kan şekeri düzeyi ortalamasının normal seviyeye-222 mg/100 ml düştüğü tesbit edildi. Böylece deneysel olarak oluşturulan diabet ortadan kalktı. Alloxan uygulamasının 1 hafta sonrasından itibaren, dejenere beta hücreleri içeren adacıklar çevresinde differensiye olan asiner hücrelerin, adacıkların içinde endokrin hücrelerle birlikte görülmeye başladıkları saptandı. Bundan sonraki zaman dilimlerinde adacıklarda asinuslardan transforme olan hücrelerin sıklıkla görülmesi, endokrin pankreasta dejenere olan beta hücrelerinin asino-insular yolla transforme olan asiner hücrelerce yenilendiklerini gösterdi.
Structural characteristics of whole pancreas was investigated with light microscopy by using histochemical technics in adult hens under normal living conditions. It was observed that, the exocrin portion was composed of acini lined up by pyramidal cells that were filled with zymogen granules at their apical halves. Initial ductules that were lined up with simple squamous epithelium were of tenly encountered among these acini. It was clearly seen that, the similar innervation was present in both of the endoerin and the exocrin cells of the gland. In the second portion of this study, the changes in blood sugar levels and in pancreatic cytology were studied following administration of 5 percent solution of alloxan tetrahyrat (250 mg per Kg of b.w. ) intravenously. It was observed that the blood sugar level which normally is 180-260 mg/100 ml went up to 315.7 mg/100 ml in first hour, and kept up increasing until the 28 th hour when reached up to the level of 396.8 mg/100 ml. The zymogen granules were lost after one hour from the alloxan treatment, that was demonstrated by the method of Gomori using chrome alum haematoxylinT-phloxine» In the en doerin Islands, the beta cells showed a typical degranulation together with nuclear pyenosis and caryolysis, which continued until 48th hour from the alloxan administration. A clear differentiation was observed in the acinar epithelia around the degenerating islands beginning in the 5th hour. The differentiation continued with the appearance of basophylic granules in the cytoplasm of acinar cells, while they were gain ing more like o spherical shape. The blood sugar level was dropped back, to normal (222 mg/100 ml) after 48 hrs. The acinar cells were detectable in the islands among the degenerated endocrin cells, in about a week from treatment. This was seen more often afterwards, and was interpreted as the regeneration by the transformation of acinar cells into beta cells.
Structural characteristics of whole pancreas was investigated with light microscopy by using histochemical technics in adult hens under normal living conditions. It was observed that, the exocrin portion was composed of acini lined up by pyramidal cells that were filled with zymogen granules at their apical halves. Initial ductules that were lined up with simple squamous epithelium were of tenly encountered among these acini. It was clearly seen that, the similar innervation was present in both of the endoerin and the exocrin cells of the gland. In the second portion of this study, the changes in blood sugar levels and in pancreatic cytology were studied following administration of 5 percent solution of alloxan tetrahyrat (250 mg per Kg of b.w. ) intravenously. It was observed that the blood sugar level which normally is 180-260 mg/100 ml went up to 315.7 mg/100 ml in first hour, and kept up increasing until the 28 th hour when reached up to the level of 396.8 mg/100 ml. The zymogen granules were lost after one hour from the alloxan treatment, that was demonstrated by the method of Gomori using chrome alum haematoxylinT-phloxine» In the en doerin Islands, the beta cells showed a typical degranulation together with nuclear pyenosis and caryolysis, which continued until 48th hour from the alloxan administration. A clear differentiation was observed in the acinar epithelia around the degenerating islands beginning in the 5th hour. The differentiation continued with the appearance of basophylic granules in the cytoplasm of acinar cells, while they were gain ing more like o spherical shape. The blood sugar level was dropped back, to normal (222 mg/100 ml) after 48 hrs. The acinar cells were detectable in the islands among the degenerated endocrin cells, in about a week from treatment. This was seen more often afterwards, and was interpreted as the regeneration by the transformation of acinar cells into beta cells.
Description
Keywords
Alloksan, Pankreas, Tavuklar, Alloxan, Pancreas, Chickens
Citation
Yakışık, M. (1988). Tavuklarda pankreasın yapısal ve histokimyasal özellikleri alloxan verilmiş tavuklarda endokrin pankreasta görülen değişiklikler üzerinde araştırmalar. Yayınlanmamış doktora tezi. Uludağ Üniversitesi Sağlık Bilimleri Enstitüsü.