Test-P-Jet

Testosterone propionate is a slower-releasing anabolic steroid with a short half-life. It is a synthetic androstane steroid derivative of testosterone. The effects of testosterone in humans and other vertebrates occur by way of two main mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5alpha-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5alpha-reductase. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects. Testosterone propionate presents a slow absorption from the intramuscular site of administration. This slow absorption is due to the presence of the less polar ester group.