Brazilian Journal of Anesthesiology (Jan 2013)
Neurotoxic Effects of Intrathecal Magnesium Sulphate
Abstract
Background and objectives: : To assess the potential neurotoxic effects at the ultrastructural level of magnesium sulfate administered intrathecally as a single or multi-dose. Methods: : Our study was conducted with 24 Sprague-Dawley rats that weighed 250-300 g. After a 4-hour fast, the rats were given 10 mg.kg-1 xylazine chloride intraperitoneal and then randomly allocated into three groups. Group I (n = 8) received 0.9% normal saline, Group II (n = 8) was given one intrathecal injection of 0.02 mL of 15% magnesium sulphate, and Group III (n = 8) was given 0.02 mL of 15% magnesium sulphate once a day for seven days. The injections were given within 0.40x50 mm from the lumbar area. After seven days, the animals were sacrificed under anesthesia with an aortic injection of 10% formaldehyde and their tissues were fixed. The medulla spinalis was then examined and histopathologically evaluated under an electron microscope. The Kruskal-Wallis test was used for statistical evaluation. A value of p < .05 was considered to be statistically significant. Results: : Significant neurodegeneration was detected in rats given single or repeated magnesium sulphate injections compared to the control group. The histopathological evaluation score of this group was also high. Conclusions: : Based on electron microscopic examination, we found that intrathecal magnesium sulphate administration induced neurodegeneration. Keywords: Magnesium Sulphate, Injections, Spinal, Toxic Actions, Microscopy, Electron.