摘要
目的观察喷他佐辛鞘内注射后切口痛大鼠背根神经节ERK1/2磷酸化表达的变化,探讨喷他佐辛脊髓镇痛的机制。方法选择鞘内置管成功的SD大鼠80只,随机分为4组(n=20):假手术组(S组)、切口痛组(P0组)、喷他佐辛40μg组(P1组)和喷他佐辛120μg组(P2组)。S组仅予吸入异氟烷麻醉,不做手术;P0组、P1组和P2组吸入异氟醚麻醉后做切口痛模型手术,并且于术前10min、术后24、48、72h分别鞘内注射0.9%生理盐水20μL、喷他佐辛40μg和喷他佐辛120μg。各组于术前1h、术后2、6、24、48、72h时采用vonFrey纤维丝测定机械缩足反射阈值(MWT),并于术后痛阈测定结束后分别处死4只大鼠,取其术侧L4和L5背根神经节用于免疫组化法测定磷酸化ERK1/2(p-ERK1/2)的阳性细胞比率。结果与S组比较,P0组术后2～72h时MWT均降低,P1组和P2组术后2～24h时MWT降低,但与P0组比较,P1组和P2组术后2～48h时MWT上升,且P2组上升更大(P<0.05)。S组背根神经节p-ERK1/2有微弱表达,P0组、P1组和P2组术后2～72h时p-ERK1/2出现强表达,但与P0组比较,P1组和P2组p-ERK1/2表达下调,而且P2组下调幅度更大(P<0.05)。结论喷他佐辛鞘内注射可提高切口痛大鼠痛阈,且与剂量相关,其机制可能与抑制背根神经节p-ERK1/2表达有关。
Objective To evaluate the effects of intrathecal（IT） pentazocine injection on expression of phospho- rylated- ERK1/2 （p -ERK1/2） in dorsal root ganglion neurons in a rat model of incision pain. Methods Eighty healthy male SD rats, weighing 220 - 250g, with IT catheter successfully placed without complication were randomly divided into 4 groups （n =20） ：group I , sham operation （Group S） ;group Ⅱ , incision pain （Group P0） ;group Ⅲ, IT pentazocine 40 （g ＋ incision pain （Group P1 ） ;group Ⅳ, IT pentazocine 120 （g ＋ incision pain（ Group P2 ）. Paw withdrawal thresh- olds to von Frey filament stimulation were measured at 1 hour before （baseline） and 2.6.24.48.72 h after operation. Ev- ery four rats from each group were sacrificed at 2.6.24.48.72 h after operation for detection of p - ERK1/2 positive rate in dorsal root ganglions of L4 and L5 using immuno - histochemistry. Results Compared with Group S, mechanical pain threshold was significantly reduced at 2 to 72 hours after operation in Group P0 and at 2 to 24 hours after operation in Group P1 and P2. However, compared with Group P0, mechanical pain threshold significantly increased in Group P1 and P2. Weak expression of p - ERK1/2 was revealed in Group S. High expression of p - ERK1/2 was revealed at 2 to 72 hours after operation in Group PO, P1 and P2. Compared with Group P0, the expression of p - ERK1/2 was significantly lower in Group P1 and P2. Conclusion Intratheeal pentazocine injection can reduce incision pain by inhibiting the up - regulation of p - ERK1/2 expression in dorsal root ganglions.
出处
《广东医学》
CAS
CSCD
北大核心
2010年第10期1221-1224,共4页
Guangdong Medical Journal
关键词
喷他佐辛
细胞外信号调节激酶
切口痛
背根神经节
鞘内注射
pentazocine
extracellular signal - regulated kinases 1 and 2
incisional pain
dorsal root ganglion
intrathecal
