In vitro tissue specificity for arsine and arsenite toxicity in the rat

The mechanism of arsine (AsH3) toxicity is not completely understood. In th is investigation, we determined AsH3 and arsenite (AsIII) toxicity in Sprag ue Dawley rat blood, liver, and. kidney, In all systems, there were dose- a nd time-dependent responses, Red blood cells were very susceptible to AsH3 toxicity. This was demonstrated by an immediate intracellular potassium los s and by hemolysis and lactate dehydrogenase (LDH) leakage that occurred by one h. AsIII concentrations up to 1 mM were not toxic to red blood cells u sing these indicators. Both AsH3 and AsIII produced toxicity in primary hep atocytes, Both produced significant LDH leakage and decreases in intracellu lar K+ by 5 h, but AsIII was more toxic than AsH3. At 24 h, both arsenic sp ecies showed similar toxicity. In renal cortical epithelial cells, AsH3 pro duced no effects on LDH and K+ over a 5-h period but produced significant L DH leakage by 24 h. In these cells, AsIII produced significant toxicity as early as in 3 h. These results showed that unchanged AsH3 produced toxicity in tissues, in addition to blood, and that toxicity of arsenicals is arsen ic species and tissue-dependent.