ncbi.nlm.nih.gov/pubmed/9790948
DHT upregulated VGEF mRNA levels.
Upon injection of Testosterone the levels shot up 7 fold the normal amount.
VGEF
Vascular Endotheilial Growth Factor:
Responsible for vasodilation indirectly through nitric oxide
Responsible for creation of new blood vessels after physical trauma to an area.
Responsible fo maintaining fibroelastic properties in penile tissue.