| 摘要: | 藥物成癮者即使在長時間戒除之後仍會顯現尋找藥物的復發行為，自20世紀70年代以來，針灸已成功被用於治療藥物成癮，但針灸對於成癮藥物引起的尋找藥物的復發行為較少被探討。研究指出在動物模式中，轉錄因子Delta FosB（?FosB）對於長期使用成癮藥物後之行為及病理學改變扮演關鍵角色。此外，?FosB可調節樹突棘的形態，其與穀氨酸接受器及神經可塑性有關。本研究測試電針合谷及曲池穴對於古柯鹼誘導的制約性場地偏好（CPP）復發作用，?FosB和AMPA GluR2蛋白表現以及樹突棘密度增加之作用，並與gabapentin，電針加上gabapentin，針刺治療，電刺激三角肌不同組別相比較。
雄性ICR小鼠在3天的時間內接受CPP訓練：其訓練模式為早晨腹腔注射古柯鹼（20 mg / kg）後將小鼠單獨放置在白色箱中30分鐘；下午在腹腔注射生理食鹽水後將小鼠單獨置於黑色箱中30分鐘。1天之後給予小鼠不同治療方式，電針條件為2 Hz，2 mA，150μs，每天一次，持續20分鐘，共8天，針刺組只有針刺沒有通電，休息2天後，給予較低劑量古柯鹼注射（10 mg / kg），並在20分鐘內測試其復發行為，之後犧牲動物收取檢體進行分生實驗。另外，以高基氏體染色實驗分析樹突棘的變化，測試連續2週給予小鼠腹腔注射古柯鹼（30mg / kg）引起樹突棘密度變化的影響，並比較有無電針的作用。實驗發現：古柯鹼有效地誘導CPP復發作用，於分生實驗中顯示伏隔核ΔFosB和AMPA GluR2的蛋白表現增加，並且增加伏隔核中樹突棘的密度。電針於合谷及曲池穴及電刺激三角肌可顯著的減少古柯鹼誘導CPP復發作用，但針刺治療則沒有作用，而局部麻醉劑注射於曲池穴附近預處理可阻斷了電針對CPP復發作用的影響。電針顯著降低古柯鹼誘導伏隔核中?FosB和AMPA GluR2蛋白的過度表現；電刺激三角肌也顯著降低了AMPA GluR2蛋白的過度表現。gabapentin可以逆轉電針對於古柯鹼誘導CPP的復發作用，也逆轉電針可降低?FosB和AMPA GluR2蛋白過度表現之作用。電針於合谷及曲池穴可降低古柯鹼誘導伏隔核中shell和core神經元樹突棘密度的增加。我們的結果不支持電針和gabapentin合併使用，與電刺激三角肌相較之下，電針於合谷及曲池穴可能是一種較理想的橈神經刺激方式，並可以減少古柯鹼誘導的復發行為和調節神經元可塑性。綜合以上結果顯示電針的作用可能是媒介ΔFosB及其下游因子AMPA GluR2蛋白表現及調節樹突棘密度。電針合谷及曲池穴可能是治療古柯鹼成癮者的有效臨床配方。
Drug addicts show reinstatement of drug-seeking behavior, even after a period of extended abstinence. Acupuncture has successfully been used for treating drug addiction since the 1970s, but how acupuncture affect the reinstatement in drug addiction has few been studied. Previous studies demonstrated that the transcription factor, Delta FosB (ΔFosB), plays a critical role in behavior and pathology after chronic use of cocaine. ΔFosB regulates the glutamate receptor and the morphology of dendritic spine and neural plasticity in animal models. This study explored the effects of electroacupuncture (EA) at acupoints LI4 and LI11 and compared them with those of other interventions, i.e. gabapentin, alone, EA at LI4 and LI11 plus GBP, manual acupuncture (MA) at LI4 and LI11, electrical stimulation at the bilateral deltoid muscle (ESD) on the reinstatement of cocaine-induced conditioned place preference (CPP), levels of ΔFosB protein expression and its target gene α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) GluR2 expression in the nucleus accumbens (NAc), as well as dendritic spine density after cocaine treatment. Male ICR mice underwent CPP training over a 3-day period: each morning, after an injection of i.p. cocaine (20 mg/kg), mice were placed individually for 30 min in a white chamber; in the afternoon, after an i.p. saline injection, mice were placed individually in a black chamber for 30 min. One day later, all mice received treatment (with or without electrical stimulation at 2 Hz, 2 mA,150 μs) for 20 min once daily for 8 days followed by 2 days rest, then they were subjected to an acute cocaine challenge (10 mg/kg, i.p.) and tested for reinstatement behavior over 20 min, before being sacrificed for Western blot assay. We investigated the effects of pretreatment with EA at LI4 and LI11 on the change of dendritic spine density induced by 2 weeks of cocaine administration (30 mg/kg, i.p.), before sacrificing the mice for Golgi staining and dendritic spine analysis. Our animal cocaine model effectively induced CPP reinstatement in behavioral test, induced overexpression of ΔFosB and AMPA GluR2, and increased dendritic spine density in the NAc in biochemistry studies. EA at LI4 and LI11 and ESD, but not MA, significantly prevented CPP reinstatement induced by a priming dose. The effects of EA on CPP reinstatement were blocked by lidocaine pretreatment, which was injected at the LI11 acupoint and contiguous with the radial nerve. EA significantly attenuated overexpression of ΔFosB and AMPA GluR2 proteins in the NAc induced by repeated cocaine exposure. ESD significantly reduced overexpression of AMPA GluR2 proteins. GBP plus EA at LI4 and LI11 significantly reversed the ability of EA to prevent cocaine-induced CPP reinstatement and attenuated the overexpression of ΔFosB and AMPA GluR2 protein levels. Pretreatment with EA at LI4 and LI11 prevented cocaine-induced increases in dendritic spine density in the NAc core and shell. Our results do not support the combined use of acupuncture and GBP. Our results also suggest that EA at LI4 and LI11, compared with ESD, may be considered as a more specific radial nerve stimulation that can potentially prevent cocaine-induced reinstatement behavior and neuronal plasticity. Our results also suggest the modulation of ΔFosB expression and its related downstream factors, AMPA GluR2 and dendritic spine density may mediate the effects of EA. Finally, we consider that EA at LI4 and LI11 is a potentially effective clinical formula for treating people with cocaine addiction. |
