Histological and Micromeasuring Studies on the Senile Changes of the Pancreas with Special Reference to a Comparison between Hawaii and Native Japanese

Abstract

In order to clarify environmental effects upon the aging process, a comparative study has been made histologically and micrometrically on the pancreas obtained at autopsy from Hawaii and native Japanese, and the results were compared with those of the similar study on the liver. It was postulated that the weight of the pancreas, the acinar tissue and of the interstitial connective tissue, and number of the acinar cells decreased gradually with age in both Japanese. The acinar cells increased in size with age only in the native Japanese, but their nuclei increased in size in both groups.
The islet tissue was not changed in volume with advancement of age. The fatty tissue was varied greatly in volume from case to case.
The estimated weights of pancreas and of acinar tissue, and sizes of both acinar cells and nuclei in the Hawaii Japanese were greater in every age decade compared with the native Japanese. These differences were more markedly noticed in the younger aged, composed of Nisei and Sansei, but less marked in the older aged, Issei. These are considered to be due mainly to an environmental, especially nutritional condition. The estimated volume of interstitial connective tissue was almost equal in Hawaii and native Japanese.
The decrease in number of acinar cells and increase in size of the nuclei were less marked compared with the results in case of the hepatic cells reported previously by the co-workers. For the discrepancy in the aging process between the pancreatic acinar cells and hepatic cells, some discussions have been made on difference in grade of the differentiation of these cells and further in their compensatory function.