conflict of interest
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It was expected that androstenedione would lead to an increase of testosterone increasing muscle mass but androstenedione seems to have no effect on muscle mass, strength or testosterone levels but does cause an increase in estrogen |
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are synthesized from cholesterol and
have the same basic 4 ringed
structure
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Anabolic Steroids try to capture the tissue building properties of testosterone |
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Steroids are carried through the bloodstream bound to a protein to keep them soluble. Since they are lipophyllic, they can traverse cell membranes. Once inside a cell they may bind to a receptor and the complex may then interact with DNA to modulate transcription, turning genes off or on. This will effect protein synthesis Binding to a Protein often changes its shape. Some steroids work in a different fashion by binding to ion channels and changing the cell's permeability to specific ions, which may in turn have a variety of effects on the cell. |
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emergency
contraception
some interesting sites to look at: NYT designing new estrogens, NYT osteoporosis, NYT women's health, No More menopause
Some examples are insulin, glucagon, adrenaline, noradrenaline, vasopressin, and melatonin
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These hormones often use a secondary messenger such as cAMP (cyclic AMP). The hormone binds to a membrane receptor which activates an enzyme (AC) which converts ATP to cAMP. The cAMP's formed can then activate a number of different enzymes. In the example at right the hormone is adrenalin and the cAMP formed activates the enzyme Protein kinase by binding to its regulatory subunit. There is then a cascade in which a series of enzymes each activate the next by attaching a phosphate. Ultimately the enzyme which makes glucose from glycogen is activated resulting in increased blood sugar. The process gets shut down by an enzyme called phosphodiesterase (PDE) which converts cAMP to AMP.
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Viagra blocks the PDE5 in erogenous
zones
include headaches, blue vision
Presumably should work for women also but Effort to Make Sex Drug for Women Challenges Experts
Diabetes results from either too little insulin production or an insufficient number of receptors. In either case the body acts as if it is starving since even though blood sugar levels are high the glucose doesn't get into the cells. The liver makes ketones to feed the brain. These sometimes give a sweet odor to the breath.
This
is a before and after picture of a diabetic who has been taking
insulin for 3 months
