Of all of these options none of them are outright safe; any site that allows you to buy testosterone by paying for it on their website you need to run for your life, as to do this you will be giving your credit card information to who knows who. As for gym dealers, this can be a tossup. If you can find a gym dealer who is not a middle man you may have a good source on your hands but understand if he gets into trouble himself he will more than likely sell you out at the first chance he gets if it saves his ass even slightly; most of them are scared and will not hold to any honorable line. Without question, when we buy testosterone on the black market there is no safe bet but there are some good sources out there who keep a low profile, use secure servers and email accounts and who are generally safe for most. In the end, understand, such purchases are illegal in many countries so if you choose this rout the risk is on you and you alone.
Neural injections of Bromodeoxyuridine (BrdU) were applied to males of both groups to test for neurogenesis . Analysis showed that testosterone and dihydrotestosterone regulated adult hippocampal neurogenesis (AHN). Adult hippocampal neurogenesis was regulated through the androgen receptor in the wild-type male rats, but not in the TMF male rats. To further test the role of activated androgen receptors on AHN, flutamide , an antiandrogen drug that competes with testosterone and dihydrotestosterone for androgen receptors , and dihydrotestosterone were administered to normal male rats. Dihydrotestosterone increased the number of BrdU cells, while flutamide inhibited these cells.