Intervention effect of the minimally invasive hematoma aspiration on repair of pyramidal tract in rat models after basal ganglia hemorrhage

Abstract

Objective To explore the effects of the minimally invasive hematoma aspiration on the repair of the pyramidal tract and improvement of neurological function. Methods Forty-eight SD male rats were equally randomized into normal control group, sham-operated group, cerebral hemorrhage group (model), model + minimally invasive hematoma aspiration at the 6th, 12th, and 24th h groups (n=8).Intracerebral hemorrhage in the later 4 groups was induced by injection of type IV collagenase + heparin into the caudate nucleus of rats, and the same amount of normal saline was injected into the sham-operated group. And then, the hematoma was lysed by injection of urokinase into the hematoma center 6, 12 and 24 h after intracerebral hemorrhage in the later 3 groups, respectively. Animals were sacrificed after behavioral function evaluation 14 d after collagenase injection. Immunohistochemistry was performed to observe the expressions of neurofilament (NF) and growth associated protein-43(GAP-43) in the posterior limb of internal capsule. Results The snatch ability of left forelimb among all the groups showed no significant differences before the success of model making (P＞0.05). The snatch ability of left forelimb in each hematoma aspiration group was much higher than that in the model group on the 14th d of collagenase injection (P＜0.05). Within the hematoma aspiration groups, the snatch ability in the group performed hematoma aspiration at the 6th h was higher than those group at the 12th and 24th h (P＜0.05). The number of NF positive fibers and the expression of GAP-43 in the 3hematoma aspiration groups were much larger or higher than those in the model group (P＜0.05); the number of NF positive fibers in the group performed hematoma aspiration at the 6th h was larger than that in those group at the 12th and 24th h (P ＜0.05); The expression of GAP-43 in the group performed hematoma aspiration at the 6th and 12th h was higher than that in the group at the 24th h (P＜0.05).Conclusion The minimally invasive hematoma aspiration performed within 24 h of intracerebral hemorrhage, especially those within 6 h, would reduce the pyramidal tract's injury, promote the repair of pyramidal tract and improve the neurological function. Key words: Intracerebral hemorrhage; Pyramidal tract; Minimally invasive hematoma aspiration