乳铁蛋白对福尔马林致痛大鼠行为学及一氧化氮合酶表达的影响

Effect of intrathecal administration with lactoferrin on formalin-induced pain behavior and spinal nitric oxide synthase

目的通过观察鞘内注射乳铁蛋白对福尔马林致痛大鼠行为学及一氧化氮合酶（NOS）表达的影响，探讨乳铁蛋白可能的抗伤害机制。方法雄性SD大鼠80只，随机分为生理盐水组（NS组）和福尔马林组（F组）；实验组分为乳铁蛋白1ug-福尔马林组（F-R1组），乳铁蛋白10ug-福尔马林组（F—R10组）和乳铁蛋白100ug-福尔马林组（F—R100组）。五组鞘内分别给予NS 20ul，NS 20ul，乳铁蛋白1ug，乳铁蛋白10ug，乳铁蛋白100ug；10min后，除NS组大鼠组底注射NS 100ul外，其余各组均给予5％福尔马林100ul。经以上处理8只动物在福尔马林处理后30min取脊髓观察NOS的表达，另8只动物在福尔马林处理后0～1h观察行为学。结果F组的缩腿舔爪的时间和脊髓NOS表达显著长于，强于NS组；预先给予乳铁蛋白能抑制以上的作用，且呈剂量依赖性。结论乳铁蛋白明显抑制福尔马林致痛大鼠痛行为及NOS表达，可能是其产生抗伤害作用机制之一。

Objective To explore the possible antinocicptive mechanism of lactoferrin by observing the effect of intrathecal administration with lactoferrin on formalin-induced pain behavior and spinal nitric oxide synthase Methods Eigthty healthy male rats were dvived randomly into five groups ： group normal saline （NS） served as the control ,group formalin （F） was treated with 5% formalin 100 ul . s. c. Group formalin ＋ tactoferrinlug（ F-R1 ）, formalin ＋ lactoferrinl ug （ F-R10 ）, formalin ＋ lactoferrinl ug （ F-R100 ） were treated respectively with lactoferrin 1 ug , 10 ug, 100 ug intrathecally before 5% formalin 100 ul injection . 30 minutes and 0-1 h after Formalin treatment, the pain behaveior of rats were evaluated and spinal cord segment were removed for expression of NOS. Result The flinching and licking time and NOS expression of Group F was largerand stronger than those of Group NS, pretreatment with lactoferrin markedly inhibited the formalin-induced response ,respectively. Conclusion Lactoferrin evidently suppressed the formalin-induced pain behavior and spinal nitric oxide synthase expression, the inhibition of spinal nitric oxide synthase might be one of the mechanisms in the antinociception of lactoferrin.