Scientists have set their mind to investigating the effects of testosterone-supplementation in male population that is receiving the hormonal therapy due to natural aging decrease in testosterone.

They started with the hypotheses that the natural decrease in testosterone may affect the progression of pre-existing cardiovascular/renal disease.
An animal model was used to investigate potential links between testosterone supplements and cardiovascular and renal disease.
They used three groups of rats: intact, gonadectomized (castrated), and testosterone-supplemented rats and who were administered with hormonal supplements via pellets. Their condition was monitored for the next five months. They measured their blood pressures and urinary protein excretion.

The results showed that testosterone-supplemented male rats had higher blood pressures in comparison to intact rats while castration had no effect on blood pressure levels. The mice on hormonal therapy excreted more urinary protein while castration reduced proteinuria (urinary protein).

It was concluded that testosterone supplementation of aging males promoted renal injury and thereby induces hypertension. Also, the removal of endogenous androgens later in life prevented hypertensive renal injury without affecting hypertension levels.