The immediate effects of AAS in the brain are mediated by their binding to androgen (male sex hormone) and estrogen (female sex hormone) receptors on the surface of a cell. This AAS–receptor complex can then shuttle into the cell nucleus to influence patterns of gene expression. Because of this, the acute effects of AAS in the brain are substantially different from those of other drugs of abuse. The most important difference is that AAS are not euphorigenic, meaning they do not trigger rapid increases in the neurotransmitter dopamine , which is responsible for the “high” that often drives substance abuse behaviors. However, long-term use of AAS can eventually have an impact on some of the same brain pathways and chemicals—such as dopamine, serotonin, and opioid systems—that are affected by other drugs of abuse. Considering the combined effect of their complex direct and indirect actions, it is not surprising that AAS can affect mood and behavior in significant ways.
This is not a routine test - A creatinine clearance test compares serum creatinine to the amount of creatinine eliminated in urine during a given time period, usually 24 hours. To start this test, you empty your bladder and flush it. Then you get to collect all your urine during the next 24 hours - nothing like carrying around a bucket full of pee to further your social life, huh? <g> During the test period, one blood sample will be taken to measure serum creatinine. Then they can compare the amount in your blood to the amount passed in your urine.
Standard values are :