The secretion of cortisol is mainly controlled by three inter-communicating regions of the body, the hypothalamus in the brain, the pituitary gland and the adrenal gland . This is called the hypothalamic–pituitary–adrenal axis. When cortisol levels in the blood are low, a group of cells in a region of the brain called the hypothalamus releases corticotrophin-releasing hormone , which causes the pituitary gland to secrete another hormone, adrenocorticotropic hormone , into the bloodstream. High levels of adrenocorticotropic hormone are detected in the adrenal glands and stimulate the secretion of cortisol, causing blood levels of cortisol to rise. As the cortisol levels rise, they start to block the release of corticotrophin-releasing hormone from the hypothalamus and adrenocorticotropic hormone from the pituitary. As a result the adrenocorticotropic hormone levels start to drop, which then leads to a drop in cortisol levels. This is called a negative feedback loop.
Cardiovascular risk factors include the alteration or diminishing of her glucose tolerance and hyperinsulinism (become resistant to insulin), a change in lipoproteins (carry cholesterol in blood) fraction which can cause cardiovascular disease and atherosclerosis (deposition of fatty substances onto inner walls of arteries causing blockage), increased triglyceride levels, hypertension (abnormally high blood pressure), changes in her myocardium (middle muscular layer of heart wall), and increased concentration levels of several different clotting factors. Cardiomyopathy (a typically chronic disorder of heart muscle that may involve hypertrophy and obstructive damage to the heart), myocardial infarction (localized death of the myocardium tissue usually leading to heart failure), heart attack, stroke, and cerebro-vascular accidents have all been causes in deaths where AAS abuse was implicated. Of course the liver, the body’s primary filtration system will come under attack as it has to accommodate the increased toxicity. Among the liver problems promoted are holestatic jaundice (failure of bile flow that causes yellowish pigmentation of skin, tissues, and body fluids), peliosis hepatis (blood-filled cysts develop on liver), hepatocellular hyperplasia (unusual increase of an epithelial parenchymatous cell called hepatocytes in the liver), and cancer. Secondary filters such as the kidneys and gallbladder also become more susceptible to disease.
Depending on the number and character of their functional groups, steroid molecules may show diverse reactivities. Moreover, the reactivity of a functional group varies according to its location within the molecule (for example, esters are formed readily by 3-OH groups but only with difficulty by the 11β-OH group). An important property of steroids is polarity —., their solubility in oxygen-containing solvents (., water and alcohols ) rather than hydrocarbon solvents (., hexane and benzene ). Hydroxyl, ketonic, or ionizable (capable of dissociating to form electrically charged particles) groups in a steroid molecule increase its polarity to an extent that is strongly influenced by the spatial arrangement of the atoms within the molecule.