Serum and testicular testosterone and nitric oxide products in aluminum-treated mice

The present investigation aimed to elucidate possible mechanisms of aluminum (Al)-induced reproductive toxicity in male mice. Daily intraperitoneal administrations of Al chloride (0, 1/8 and 1/3 LD 50) were conducted for 12 or 16 days, followed by a 2-week withdrawal period. Serum Al levels significantly increased in Al-treated animals, compared to controls, whereas serum testosterone concentrations were markedly decreased. In addition, significant increases in nitric oxide products (NO x ) were also observed during Al injection. Similar trends were found for testicular Al, NO x and testosterone levels. However, during the withdrawal period, when diminished testicular Al levels were observed, the changes in NO x and testosterone levels were indistinguishable from control values. It was concluded that: (i) Al exerted a significant adverse effect on the steroidogenesis; (ii) the process was reversible; and (iii) increased production of NO x , induced by excessive Al, might inhibit testosterone levels.