Pancreas is the most organ involved in diabetes mellitus. Insulin secreted by the pancreas was found to prolong the life of diabetics.
A longish and flat organ situated in the center of the abdomen is the pancreas and is lodged within the curve of the duodenum just behind the stomach. It weighs about 75gm and is about five to six inches long. The pancreas has various functions with one being the secretion of digestive enzymes. Another one is the secretion of two hormones from islands of cells called Islets of Langerhan. The islets consist of two types of very specialized cells – the beta cells which secrete insulin and the alpha cells which secrete glucagon. Secretion of insulin is automatic in response to the glucose level in the blood in the normal person.
The failure of the beta-cells in the pancreas to secrete insulin is a very crucial factor in diabetes. However, for specific types of diabetes, there is a delay in insulin secretion in response to glucose combined with insulin resistance. Obesity is often related to insulin resistance.
Apart from the above facts, there are also other factors involved in diabetes mellitus. That is the reason some complications of diabetes still persist despite the fact of good glucose control.