鞘内注射胍丁胺对骨癌痛大鼠痛觉及脊髓背角NMDA受体1表达的影响

Effect of intrathecal agmatin on hyperalgesia and spinal dorsal NMDA receptor 1 expression in mice with bone cancer pain

目的观察鞘内注射胍丁胺对骨癌痛大鼠痛觉及脊髓背角NMDA受体1(NR1)表达的影响。方法成年雌性Wistar大鼠,体重180～220g,假模型组(A组,n=14)接种PBS液,骨癌痛模型制作成功大鼠随机分为三组,其中B组(n=14)不行鞘内注射,另两组分别鞘内注射生理盐水10μl(C组,n=14)和胍丁胺160mg/kg(D组,n=14)。用vonFrey丝测定大鼠机械缩足反射阈值(MWT),于鞘内注射后120min用Westernblot方法测定脊髓背角NR1蛋白的表达。结果建模7d后B、C和D组大鼠MWT明显低于A组(P<0.05),鞘内注射胍丁胺后D组MWT显著高于B、C组(P<0.05)。鞘内给药120min后B、C、D组NR1蛋白的相对表达量明显高于A组(P<0.05),D组明显低于B、C组(P<0.05)。结论鞘内注射胍丁胺可通过抑制大鼠脊髓背角NR1的表达减轻胃癌痛。

Objective To investigate the effect of intrathecal agmatin on hyperalgesia and spinal dorsal NMDA receptor 1 expression in mice with bone cancer pain. Methods Fifty-six adult female SD rats weighing 180-220 g were randomly divided into 4 groups with 14 each： sham operation group （group A） bone cancer group（group B） control group（group C） ; agmatin group（group D）. Group C and D received intrathecal injection with 10 ul saline or 160 mg/kg agrnatin. Mechanical paw withdrawal latencies（MWT） was measured by yon Frey silk. The expression of NR1 was investigated 120 rain after intrathecal agmatin treatment. Results MWT was significantly decreased in group B,C, D than group A 7 days after successful bone cancer pain model building（P〈0.05）. MWT was higher in group D than group B and C（P〈0.05）. The expression of NR1 was increased in group B,C,D than group A（P〈0.05）. The expression of NR1 was lower in group D than group B and C（P〈0. 05）. Conclusion This study shows that agmatin may be involved in the mechanism of bone cancer pain through NMDA receptor.