Write 4 page essay on the topic Anatomy and Physiology: diabetes mellitus.Download file to see previous pages... There are more than 20 million people suffering with diabetes mellitus in the United St

Write 4 page essay on the topic Anatomy and Physiology: diabetes mellitus.

There are more than 20 million people suffering with diabetes mellitus in the United States (Center of Disease Control, 2005). In other words every 14th American has this serious health disorder. Furthermore, 29.8% of affected persons do not know about their disease - they have undiagnosed form (CDC, 2005).

There are three main forms of diabetes mellitus (accordingly to International Classification of Diseases, 1994/2003): type I diabetes, type II diabetes and gestational diabetes. All these form has different etiology and only clinical manifestations are similar for them. But what is the distinct and what anatomical structures and physiological processes are responsible for normal regulations of carbohydrate metabolism.

It's known that the first key discover in the clarification of diabetes etiology was made when German scientists von Mering and Minkowski proved that the pancreas play important role in preventing symptoms of diabetes. In 1910 British physiologist Sharpey-Schafer supposed the unknown chemical substance is responsible for normalizing blood sugar level. He called this agent as "insulin" (Patlak, 2002). Nevertheless insulin was discovered only in 12 years, thus there were no medicine before Banting and Best isolated insulin from canine and, later, bovine pancreas. They were first who used insulin for treatment of diabetic patients and they were awarded with Nobel prize for this invention (Patlak 2002, Porte et al., 2002).

AnywAnyway pancreatic secretion of insulin is one of the most important factors of diabetes developing. If the tissue of pancreas is changed due to congenital disease, toxic injury, inflammation or trauma than the quantity of insulin secreting by the islets of Langerhans (the groups of specialized cells of pancreas) will be decreased. Correspondingly the effects of insulin became weaker. The injection of insulin can treat this condition. This is the principal pathogenetic scheme of type I diabetes (Kahn, 2004).

Another model is characteristic for type II diabetes. In this disease the level of insulin secretion is normal but there are the deficit of insulin receptors in the target cells. In other words, this condition is characterized with insulin resistance and there is no dependence on insulin level in the blood (Porte et al., 2002). Let's discuss the mentioned mechanisms in the details. Accordingly to the recent publications (Kahn et al., 2004) the most frequent cause of type 1 diabetes is an autoimmune destruction of -cells in the islets of Langherhans. 90% of type 1 diabetics have islet cell cytoplasmatic antibodies, 80% of them have islet cell surface antibodies. Thus presence of high titres of such antibodies are an important predictor of the risk of type 1 diabetes mellitus development. Other immunological indices also important for understanding pathogenesis and diagnostics of type 1 diabetes, e.g. anti-GAD (glutamic acid decarboxylase) antibodies and anti-insulin antibodies (Ishii et al., 2005 ). The active autoimmune processes result in a deficiency of insulin and occurrence of the clinical manifestations of diabetes mellitus. Nevertheless some cases of type 1 diabetes may not have autoimmune origin (Kahn et al., 2004). Recently conducted researches allowed to determine the role of heredity in the development of type 1 diabetes, particularly by detecting MODY (maturity onset diabetes) mutations responsible for some cases of the disease amongst young patients (Krzentowski, 2005. Arky, 2005).

Type 2 diabetes has more complicate etiology.