Biochemical bases of hyper- and hypofunction of pancreas

Hyperfunction of pancreas with regard to insulin is observed in non-malignant tumor of B-cells of pancreas and overdose of insulin. It results in hypoglycemia which expressed by weakness, increased sweating, decreased vision. Emergancy is injection of glucose.

Diabetes mellitus is a lack of insulin or its receptors. There are insulindependent (IDDM) and insulinindependent (IIDM) diabetes mellitus. Diagnosis of diabetes mellitus is based on the level of glucose in blood, glucosuria, ketonemia and ketonuria. If the level of glucose on empty stomach is more than 7.8mM/l so it is diebetes mellitus. If the level of glucose in occasional sample of blood plasma is more than 11.1mM/L so it is also diabetes mellitus.

IDDM is associated with deficiency of insulin. IIDM is associated with lack of receptors or excess of contrinsular hormones.

There are diabetes related with absence of free insulin and presence of coupled one (it is due to the action of coupled insulin on adipose tissue where lipogenesis is increased). Such patients are fatty. But another type of diabetes is associated with absence both of forms of insulin. Such patients are skinny (thin).

There are 3 main symptoms of diabetes mellitus: polyuria, polyphagia and polydypsia. Biochemical analysis show hyperglycemia, glucosuris, ketonemia and ketonuria.

Hyperglycemia is associated with deficiency of insulin and excess of contrinsular hormones because glucose doesn’t enter the cells and isn’t used in them. It results in polyphagia (hunger). High level of glucose causes dehydration of tissues because water exits from cells and enters the vessels to dissolve the blood. If the level of glucose is more than renal threshold of its the glucose passes through kidneys in urine and glucosuria is developed. Glucose draws water therefore polyuria is observed. Polyuria causes polydypsia (thirsty).

High level of glucose in blood plasma causes formation of glycosylated hemoglobin. Such hemoglobin doesn’t carry out its function and hypoxia occurs. It results lactate acidosis.

Excess of contrinsular hormones leads to increased lipolysis and subequent ketogenesis. Ketonemia and ketonuria are developed.

In insulinindependent tissues fructose-sorbitol pathway is activated. It results in lesion of these tissues (micro- and macroangiopathies, cataracts, retinopathy, nephropathy, trophic ulcerus)

Hormones of adrenal glands

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The chemical structure, target-cells, mechanism of action, physiologic effects, regulation of secretion of glucagon	\|	Glucocorticoids: chemical structure, target-cells, mechanism of action, physiological effects

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