Age-related pancreatic tissue postnatal histogenesis in the albino rat (Rattus norvegicus): A morphological, morphometrical, and immunohistochemical study with emphasis on alpha and beta cells

Abstract

Age is an essential factor that causes histological changes in the body's cells, tissues, and organs, affecting the functioning of all body systems. This study aimed to assess the histological changes of the pancreas during the stages of its lifetime. Seventy-two male rats of different ages were used in the present investigation to study the histological changes of the pancreas during age progress from birth until puberty with an impact on alpha and beta cells. The samples were categorized into six groups according to the postnatal ages; 1, 7, 14, 21,30, and 70 days. The results showed that the pancreas did not appear clearly in rats of one day and 7 days old, while the shape and lobes of the pancreas were clearly observed in rats of 14 days old and the subsequent ages. Histologically, the serous acini, duct system, and islet of Langerhans were ill-developed in the first two ages and became well-developed at 21 days old. Statistical analysis showed that the number of alpha and beta cells in histological sections of the pancreas of the islets of Langerhans shows a decrease in the alpha cells with age progress. At the same time, it was observed that the number of beta cells increased gradually with age advancement; at the same time, serum insulin level increased, and glucagon decreased with age advancement. The current study revealed that pancreatic tissue histogenesis continues in postnatal life, at least through the first 2 weeks in rats where dramatic changes in pancreatic tissue occurred, including the endocrine portion.

Keywords

• rat
• pancreas
• alpha cell
• beta cell