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Case Study: Anabolic Steroids and the Endocrine SystemWhat are steroid hormones?Steroid hormones are lipid-based and lipid-soluble, and are composed of four carbon-based rings. Steroids include cholesterol, a component of animal cell membranes, estrogen, which regulates sexual function in females, and increases the storage of fat, and testosterone, which regulates sexual function, and aids the building of bone and muscle mass.How steroid hormones work: The lipid-soluble hormone diffuses through a cell membrane and into the cytoplasmThe hormone binds to a steroid-receptor complex inside the nucleusThe receptor acts as a transcription factor and binds to a promoter region in the DNA, initiating transcriptionThe resulting mRNA leaves moves to a ribosome, beginning protein synthesisWhat are anabolic steroids?Anabolic steroids are compounds that are made to mimic male sex hormones. They come in the form of a pill, gel, cream, or injection, and are used to build muscle mass in people who have anemia, osteoporosis, cancer, and HIV/AIDS, or to treat problems that result in low testosterone levels. In Canada, a prescription is needed to legally obtain anabolic steroids. However, there is a market for illegal anabolic steroids, which are used by people, including some professional athletes, to increase muscle mass, improve endurance, build strength, and lower body fat. In most competitive sports, the use of anabolic steroids is banned.Anabolic steroids were first created in the 1930’s, in order to create synthetic testosterone to treat men who did not have enough testosterone for growth and development. During the Second World War, artificial testosterone was found to be helpful for the performance of soldiers. Anabolic steroids became popular among Olympic, professional, and even high school athletes. By 1976, steroid use was banned from the Olympics. In 1988, the Anti-Drug Abuse Act was passed, and the possession and distribution and anabolic steroids became considered a felony in the United States.Advantages and DisadvantagesOverview:AdvantagesDisadvantagesGreater muscle massIncreased protein synthesisIncreased bone-mineral contentHigher red blood cell countFaster healingHigher self-esteemShort-TermLong-TermReduced sperm count (men)Heart damageImpotencePain while urinatingExcessive hair growth (women)Breast reduction (women)AcneWeight-gainHigher blood pressureSwellingWater retentionLiver diseaseBreast development (men)Testicle shrinkage (men)Deepened voice (women)Enlarged clitoris (women)Abnormal menstrual cycles (women)Heart attacksDamage to the liver Damage to reproductive organsHair-lossLowered HDL cholesterol and increased LDL cholesterolThe use of steroids can have some positive effects: they can raise confidence, improve the absorption of minerals, lower body fat, and increase muscle mass. However, the gained muscle mass must be maintained through regular training.Steroid usage may also cause mood swings and depression. Over time, self-consciousness may develop as side-effects such as hair-loss, acne, increased body hair on women, breast growth in men, and weight-gain begin to appear.Anabolic Steroids, the Endocrine System, and HomeostasisEndocrine glands secrete hormones, which travel through the bloodstream to produce an effect on target cells or organs. For example, steroid hormones trigger the production of certain proteins. Over time, when a released hormone is no longer needed, enzymes deactivate the hormones and break them down. One dose of an illegal anabolic steroid can be 10 to 100 times greater than a prescribed dose. Injections of high amounts of hormones may shock the body, and as the injections are repeated, it is difficult for the body to rid itself of the extra hormones. The injected steroids therefore remain in the bloodstream, and continue to initiate transcription, causing excess protein synthesis. This puts a strain on the body, as energy is spent on synthesizing proteins and deactivating and removing hormones.Many hormones are regulated by negative feedback loops, through which homeostasis, the keeping of a constant internal environment, is maintained. Regular injections of anabolic steroids disrupt these feedback loops, preventing the endocrine system from easily maintaining homeostasis.Sources ................
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