Lol your treating the brain & HPTA as these separate entities - they're not.
As for the impact of AAS on the brain, well clearly SOMETHING is going on:
http://www.ncbi.nlm.nih.gov/pubmed/25986964
"This multimodal magnetic resonance imaging study of the brain compared 10 male weightlifters reporting long-term AAS use with 10 age-matched weightlifters reporting no AAS exposure...
AAS users had larger right amygdala volumes than nonusers (P=0.002) and reduced rsFC between right amygdala and frontal, striatal, limbic, hippocampal, and visual cortical areas."
And no, I'm not going to sit here and educate you about Leydig cell function since you've provided nothing of substance to counteract any of the evidence I've given.
All I will say is that the study you posted actually serves as evidence that these cells are NOT fully developed during puberty - in other words it backs my position up:
"In human puberty, the situation appears to be less clear in that, while circulating INSL3 concentrations increase as expected, by Tanner stage 5 they appear still not to have attained by some large margin the concentrations observed in young adulthood [
45,
46].
This would imply that there is still substantial development of the Leydig cells in young men subsequent to reaching Tanner stage 5 at around 15–17 yr of age."
The data indicates that AAS has an impact on the brain - what this impact means we don't really know.
The data indicates that brain development continues into the mid 20s.
The data indicates that Leydig Cells are NOT fully developed until the early 20s.
The leading hypotheses among professionals regarding the lack of recovery post AAS concerns Leydig Cell dysfunction. The data isn't conclusive but its the best answer we have at the moment.
No deflections, no personal attacks, no subject changes