Intracerebral microinjection of stannous 2‐ethylhexanoate affects dopamine turnover in cerebral cortex and locomotor activity in rats

Stannous 2-ethylhexanoate [Sn(Oct)(2)] is used as a catalyst for production of poly-L-lactic acid and copolymers that are implanted in cranial surgery, but reports on its effects on the central nervous system are few. We examined the effects of Sn(Oct)(2) on cell viability in vitro and on neurotransmission and behavior in the rat. Treatment of normal human astrocytes with 10 mg/mL Sn(Oct)(2) reduced mitochondrial activity to 16% of the control. Injection of Sn(Oct)(2) at 6.28 mg/kg BW (2 mg/kg BW Sn) into right lateral ventricle of the rat brain tended to increase the ambulation distance after 30 days when compared with the control group. The turnover of dopamine neurotransmission was increased in the cerebral cortex. These results suggest that Sn(Oct)(2) is cytotoxic to astrocytes in vitro. Injection of Sn(Oct)(2) into the brain had no or very weak immediate neurotoxicity, but long-term exposure to Sn(Oct)(2) increased dopamine neurotransmission turnover.