Efeitos do Dantrolene sódico em ratos adultos com trauma medular agudo experimental

Abstract

The effect of dantrolene sodium was evaluate on acute spinal cord injured rats. 46 male Wistar rats, three months old, were randomized in six groups: GI (positive sham - 32 hours); GII (negative sham - 32 hours); GIII (dantrolene 32 hours); GIV (positive sham - eight days); GV (negative sham - eight days); GVI (dantrolene - eight days). Was performed laminectomy at T13 in all rats, and GI, GIII, GIV and GVI were also submitted to spinal cord injury, by a stereotaxic equipment, with a weight of 70,5g, during five minutes. One hour later, GIII and GVI received 10mg/kg of dantrolene in a single intraperitoneal injection, and GI and GIV, placebo. Were evaluated painful sensibility, locomotor capacity, proprioceptive and tactil placing, inclined plan and seric biochemical profile. After euthanasia, skin, esqueletic muscle, diaphragm, heart, lung, liver, spleen, kidney, bladder, and spinal cord were collected for histology. Were performed TUNEL and immunochemistry (anti-NeuN). The traumatized animals showed paraplegia and urinary retention. No difference was observed in the behavioral tests or biochemical evaluation among the groups, however, those treated with dantrolene showed the least bladder injury at eight days (p0,05). In all injured rats was observed malacia at injury epicenter. The animals treated with dantrolene showed smaller amount of TUNEL-positive neurons, emphasizing its antiapoptotic effect, and bigger amount of NeuN-positive neurons, at 32 hours and eight days after trauma (p0,05). Its conclude that dantrolene presents protective effect on bladder and spinal cord