Sex Hormones, Adrenal Cortisol, Prostaglandins Curator: Larry H. Bernstein, MD, FCAP Steroids A major class of lipids, steroids, have a ring structure of three cyclohexanes and one cyclopentane in a fused ring system as shown below. There are a variety of functional groups that may be attached. The main feature, as in all lipids, is the large number of carbon-hydrogens which make steroids non-polar. Steroids include such well known compounds as cholesterol, sex hormones, birth control pills, cortisone, and anabolic steroids. http://www.elmhurst.edu/~chm/vchembook/images/556cholesterol.gif The best known and most abundant steroid in the body is cholesterol. Cholesterol is formed in brain tissue, nerve tissue, and the blood stream. It is the major compound found in gallstones and bile salts. Cholesterol also contributes to the formation of deposits on the inner walls of blood vessels. This topic was covered in the previous discussion of the lipids series, and extensively in cardiovascular topics. Cholesterol is synthesized by the liver from carbohydrates and proteins as well as fat. Therefore, the elimination of cholesterol rich foods from the diet does not necessarily lower blood cholesterol levels. Some studies have found that if certain unsaturated fats and oils are substituted for saturated fats, the blood cholesterol level decreases. The research is incomplete on this problem. Cholesterol exists as an ester with fatty acids.What is the functional group at carbon 3 which is used to make an ester? OH is alcohol What is the feature on carbon 17? Branched long hydrocarbon chain Sex Hormones http://www.elmhurst.edu/~chm/vchembook/images/556sexhormones.gif The primary sex hormones, testosterone and estrogen, are responsible for the development of secondary sex characteristics. Two female sex hormones, progesterone and estrogen or estradiol control the ovulation cycle. Notice that the male and female hormones have only slight differences in structures, but yet have very different physiological effects. Testosterone promotes the normal development of male genital organs and is synthesized from cholesterol in the testes. It also promotes secondary male sexual characteristics such as deep voice, facial and body hair. Estrogen, along with progesterone regulates changes occurring in the uterus and ovaries known as the menstrual cycle. Estrogen is synthesized from testosterone by making the first ring aromatic which results in the loss of a methyl group and formation of an alcohol group. List three functional groups in progesterone? C#3 & #17 are ketones; C#4&5 are alkenes; What is difference between progesterone and testosterone? testosterone has C#17 alcohol vs ketone on progesterone What is difference between testosterone and estrogen? Estrogen has C#3 alcohol, + aromatic first ring; […]![]()
