Neuroprotective effects of hydrogen sulfide in rats with acute cauda equina syndrome / 中国组织工程研究

ABSTRACT

BACKGROUND:Endogenous hydrogen sulfide can be used as a new gaseous signaling molecule, and has important signal transfer function and biological regulation effects. OBJECTIVE:To study the neuroprotective effects of hydrogen sulfide in rats with acute cauda equina syndrome. METHODS: The 72 Sprague-Dawley rats were randomly assigned to three groups. Experimental group, model group laminectomy was performed at the lumbar 4 (L4) level of the vertebra, and a piece of silicone (10 mm long, 1 mm thick, and 1 mm wide) was placed under the laminae of the L5-6 vertebra to produce the animal model of cauda equina syndrome. Sham surgery group a simple laminectomy was performed in L4, but silicone was not implanted. In the experimental group, 20 μmol/kg NaHS was injected intraperitonealy at 1 hour before model establishment. Model and sham surgery groups an equal volume of saline was injected intraperitonealy. At 12, 24, 48 and 72 hours after model establishment, malonaldehyde and glutathione levels in cauda equina nerve tissue were detected. Simultaneously, hematoxylin-eosin staining and TUNEL staining were performed at 48 hours. RESULTS AND CONCLUSION:Hematoxylin-eosin staining demonstrated that cauda equina nerve tissue was dense and regular, with complete myelin sheath, no axon sweling in the sham surgery group. Cauda equina nerve tissue was sparse, with the presence of demyelination, and partial axons and myelin sheath sweling in the model group. Cauda equina nerve tissue was tight, with axonal sweling and demyelination in the experimental group. TUNEL staining demonstrated that the number of positive cels was less in the spinal cord and dorsal root ganglia in the sham surgery group. Abundant positive cels were detected in the spinal cord and dorsal root ganglia in the model group. The number of positive cels was significantly lower in the experimental group than that in the model group. Malonaldehyde levels were lower in the sham surgery and experimental groups than in the model group (P < 0.05, P < 0.01), but glutathione levels were higher than model group (P < 0.05,P < 0.01). These results indicated that hydrogen sulfide could decrease oxidative stress and protect cauda equina nerve in rats with acute cauda equina syndrome.