短肽P10581对前列腺癌骨转移的镇痛效果及对吗啡镇痛耐受的影响

Analgesic effect of short peptide P10581 on metastatic bone cancer pain and its effect on morphine analgesic tolerance

目的探讨短肽P10581对前列腺癌骨转移的镇痛效果及对吗啡镇痛耐受的影响。方法首先,将前列腺癌PC3细胞注入大鼠胫骨建立前列腺癌骨转移模型,分组(n=4)检测大鼠机械性缩足阈值(paw withdral threshold,PWT),筛选短肽P10581的最佳镇痛浓度,并取大鼠背根神经节DRG神经元,Western blot法检测压电蛋白Piezo2蛋白。其次,大鼠模型随机分为吗啡组(5 mg·kg-1)、P10581 A组(6.4μg·kg-1)、P10581 B组(12.8μg·kg-1)和生理盐水组(n=10),皮下注射相应药物后,每小时测量大鼠PWT。另外,大鼠模型随机分为吗啡组(5 mg·kg-1)、复合用药Ⅰ组(0.2μg·kg-1 P10581+5 mg•kg-1吗啡)、复合用药Ⅱ组(0.4μg·kg-1 P10581+5 mg·kg-1吗啡)、生理盐水组(n=10),记录皮下注射后7 d内大鼠PWT。结果短肽P10581对前列腺癌骨转移模型的最佳镇痛浓度为51.2μg·kg-1,在此浓度下,大鼠DRG神经元中Piezo2表达降低,差异有统计学意义(t=3.569,P<0.05)。在镇痛效果研究中,给药后3 h内三组均有明显镇痛效果,且吗啡组镇痛效果强于P10581 A组和P10581 B组;第4 h时,三组的镇痛效果无差异(P>0.05);7 h后,与吗啡组相比,P10581 A组(t=11.60,P<0.001)和P10581 B组(t=28.84,P<0.001)镇痛效果显著。在短肽P10581对吗啡耐受性影响的研究中,单独使用吗啡时,自第2 d起镇痛效果随时间减弱,出现吗啡耐受;微量短肽P10581与吗啡联合使用时,相比吗啡组,第7 d复合用药Ⅰ组(t=38.41,P<0.001)和复合用药Ⅱ组(t=34.92,P<0.001)的镇痛率分别提高了61.31%和69.78%,仍保持明显的镇痛效果。结论相较于吗啡,短肽P10581对前列腺癌骨转移的镇痛作用更具有时间优势,并且微量短肽P10581可明显降低吗啡耐受性。

Objective To investigate the analgesic effect of short peptide P10581 on prostate cancer bone metastasis and its effect on morphine analgesic tolerance.Methods First,prostate cancer PC3 cells were injected into the tibia of rats to establish a bone metastasis model of prostate cancer,and the paw withdral threshold(PWT)was detected in groups(n=4)to screen the optimal analgesic concentration of the short peptide P10581.Rat dorsal root ganglion DRG neurons were taken and the piezoelectric protein Piezo2 protein was detected by Western blot assay.Secondly,the rat models were randomly divided into the morphine group(5 mg·kg-1),the P10581 A group(6.4μg·kg-1),the P10581 B group(12.8μg·kg-1),and the normal saline group(n=10),and the PWT of rats was measured hourly after subcutaneous injection of the corresponding drug.In addition,the rat models were randomly divided into the morphine group(5 mg·kg-1),the compound drug I group(0.2μg·kg-1 P10581+5 mg·kg-1 morphine),the compound drugⅡgroup(0.4μg·kg-1 P10581+5 mg·kg-1 morphine),and the normal saline group(n=10),and the rat PWT was recorded within 7 days after subcutaneous injection.Results The optimal analgesic concentration of the short peptide P10581 in the bone metastasis model of prostate cancer was 51.2μg-kg-1,at which Piezo2 expression was reduced in rat DRG neurons,and the difference was statistically significant(t=3.569,P<0.05).In the analgesic effect study,the analgesic effect was obvious in the three groups within 3 h after administration,and the analgesic effect in the morphine group was stronger than that in the P10581 A group and the P10581 B group.At the 4th hour,there was no difference in analgesic effect between the three groups(P>0.05).After 7 h,the analgesic effect was significant in the P10581 group A(t=11.60,P<0.001)and the P10581 group B(t=28.84,P<0.001),compared with the morphine group.In the study of the effect of short peptide P10581 on morphine tolerance,when morphine was used alone,the analgesic effect decreased with time from the 2nd day onwards,and morphine tolerance appeared.When the trace short peptide P10581 was combined with morphine,the analgesic rates of the compound drug I group(t=38.41,P<0.001)and the compound drug groupⅡ(t=34.92,P<0.001)increased by 61.31%and 69.78%,respectively,on the 7th day,with obvious maintained analgesic effects.Conclusion Compared wit morphine,the analgesic effect of short peptide P10581 on bone metastasis of prostate cancer had a time advantage,and trace short peptide P10581 could significantly reduce morphine tolerance.