Cortisol – inspection in the physiology and stress

Abstract

Cortisol, also called “the” stress hormone is a glucocorticoid secreted by the adrenal cortex. This hormone plays a significant role in maintaining homeostasis, according to the body’s total stress. Cortisol interferes with many organs, affects glucose and fatty acids metabolism and neurotransmitter secretion. Predominantly, cortisol influences the carbohydrate metabolism, stimulating gluconeogenesis in the liver and inhibiting glucose utilization in peripheral tissues. As it is an element “fight or flight” it also stimulates central nervous system and enhances blood flow. To some extent cortisol influences also the renal handling of electrolytes, namely: increasing sodium resorption, and renal excretion of potassium, calcium and phosphates. Through its anti-inflammatory and immunosuppressive character this glucocorticoid modulates the immune system functioning. Cortisol has a circadian rhythm following ACTH (adrenocorticotropic hormone) secretion. Increased cortisol levels are observed physiologically during stress and pathologically in Cushing’s syndrome. Chronic hypercortisolism is harmful or the body, and its effects present an extremely wide spectrum, including insulin resistance, obesity, insomnia and even depression. Thus, laboratory diagnosis of cortisol level is important for the diagnosis, monitoring and evaluate the effectiveness of hypercortisolism treatment.