大鼠侧脑室注射Ad-NEP对大鼠脑脊液β-内啡肽的影响

目的 探讨大鼠侧脑室注射不同滴度表达β-内啡肽的重组腺病毒(Ad-NEP)对脑脊液β-内啡肽的影响.方法 选择雄性SD大鼠36只随机均分为6组:A、B、C、D和E组,分别于侧脑室注射滴度为5×107、5×108、5×109、5×1010和5×1011噬菌斑形成单位(PFU)的Ad-NEP;F组作为空白对照.4d后测定脑脊液中β-内啡肽的浓度.结果 C组和D组脑脊液中β-内啡肽的浓度明显高于F组[(667.80±121.50) pg/ml和(974.65±174.97) pg/ml vs.(76.20±7.13) pg/ml](P＜0.01).结论 使用5×109和5×1010PFU两种滴度的Ad-NEP侧脑室注射是提高实验大鼠脑脊液β-内啡肽浓度的较好选择.     

脑出血患者血浆和脑脊液中β-内啡肽、强啡肽A1-13含量及纳络酮的影响

目的：探讨脑出血患者血浆和脑脊液中β-内啡肽（β-EP）、强啡肽A1-13（DynA1-13）的含量及纳络酮对其影响．方法：将60例脑出血（ICH）患者随机分为对照组（n=30）和纳络酮组（n=30）。对照组采用常规治疗,纳络酮组在常规治疗基础上加用纳络酮3．0mg／d静脉滴注,两组均治疗14d。采用放射免疫分析法（RIA）,检测60例脑出血患者急性期和治疗14d后血浆和脑脊液中β-EP、DynA1-13的含量变化,并设立正常对照组,观察不同部位、不同出血量时上述指标的变化,观察纳络酮对血浆和脑脊液中β-EP、DynA1-13的影响。结果：（1）脑出血患者血浆和脑脊液中β—EP、DynA1—13含量在急性期较正常组明显增高,且有显著性差异（P〈0．01）;（2）不同部位出血患者之间血浆和脑脊液中β—EP、DynA1-13含量的差别不大,无显著性差异（P〉0．05）;（3）脑出血患者血浆中β—EP、DynA1-13含量与出血量呈显著正相关（r1=0．663、r2=0．480,P〈0．01）,脑出血患者脑脊液中β—EP、DynA1—13含量与出血量呈显著正相关（r1=0．645、r2=0．380,P〈0．01）。（4）脑出血患者血浆和脑脊液中β—EP、DynA1-13含量,治疗结束后两组比较有显著性差异（P〈0．05或P〈0．01）。结论：（1）β—EP、DynA1-13参与了脑出血的病理生理过程;（2）纳络酮能拮抗β—EP、DynA1-13所引起的中枢神经系统损伤,具有脑保护作用。     

腹腔注射丹参注射液对新生大鼠缺氧缺血性脑损伤的影响

目的：观察腹腔注射丹参注射液对新生大鼠缺氧缺血性脑损伤(HIBI)后血浆、皮层β-内啡肽、亮啡肽免疫活性物质(ir-β-EP、ir-LEK)含量的影响。方法：在新生大鼠HIBI后即刻及其后每12h向腹腔注射丹参注射液，每次每只0．5mL。采用放射免疫分析法观察损伤后不同时间血浆、皮层ir-β-EP、ir—LEK含量的变化。结果：HIBI后血浆ir-β-EP、ir—LEK含量、患侧皮层ir-β-EP含量不同程度升高，而以血浆ir-β-EP升高更明显、持续时间更长。腹腔注射丹参后血浆、患侧皮层ir-β-EP水平的上升被部分逆转，以血浆升高的抑制更为显著。结论：外周及中枢β-内啡肽、亮啡肽参与HIBI的病理生理过程；腹腔注射丹参注射液部分逆转新生鼠HIBI后外周和中枢ir-β-EP水平的异常升高．可能是丹参促进损伤后脑功能恢复的作用之一，     

纳洛酮对敌敌畏中毒家兔血浆β-内啡肽含量的影响

目的 研究纳洛酮对敌敌畏中毒家兔血浆β-内啡肽含量的影响.方法 将家免分为两组,均采用敌敌畏灌胃法使其中毒,常规治疗组予硫酸阿托品和碘解磷定治疗,纳洛酮预防组在中毒前予纳洛酮,中毒后予硫酸阿托品和碘解磷定治疗,分别测定两组动物敌敌畏中毒前和中毒治疗后不同时间血浆β-内啡肽含量.结果 与正常动物相比,常规治疗组血浆β-内啡肽水平在中毒治疗后1～20 h均显著升高(P<0.001);与常规治疗组相比,纳洛酮预防组血浆β-内啡肽水平在中毒治疗后1～20 h均显著降低(P<0.01).结论 家兔急性敌敌畏中毒可引起血浆β-内啡肤水平急剧升高,纳洛酮预防性应用则可明显降低中毒家兔血浆β-内啡肽水平.     

褪黑素对大鼠脑内β-内啡肽、去甲肾上腺素和5-羟色胺释放的影响

目的　观察褪黑素(MLT)对大鼠脑内β-内啡肽(β-Ep)、去甲肾上腺素(NE)及5-羟色胺(5-HT)释放的影响,以探讨MLT镇痛作用机制。方法　结合痛阈测定,放免测定第三脑室推挽灌流液中β-Ep样免疫活性物质(ir-βEp)含量;高效液相色谱法测定脑内微透析液中NE和5-HT的代谢产物。结果　ipMLT110mg·kg^-1可显著增加第三脑室灌流液中ir-βEp含量,同时显著提高大鼠痛阈;但对中脑导水管周围灰质(PAG)、下丘脑微透析液中3-甲氧基-4-羟基苯乙二醇、5-羟吲哚乙酸含量无显著影响。结论　MLT可促进脑内β-Ep的释放,可能是其镇痛作用的机制之一;MLT的镇痛作用与PAG、下丘脑内NE、5-HT的释放可能无关。     

β-内啡肽对更年期妇女血管功能的影响

目的 探讨更年期妇女外周血浆β-内啡肽水平的变化对其血管功能的影响.方法 将101例更年期妇女(45岁～60岁),根据症状、血压、绝经情况进行分组,各组妇女均进行外周血浆β-EP和一些相关指标测定[血栓素A2(TXA2)和前列环素(PGI2)].结果 ①有血管舒缩紊乱症状(如潮热、头晕)的妇女组β-EP水平低于无症状妇女组,与对照组比较有显著差异(P＜0.002,P＜0.05).②围绝经期妇女β-EP水平的变化对血压无显著影响(P＞0.05).③围绝经期妇女血浆β-EP水平的变化对TXA2和PGI2的水平及比值均无明显影响.结论 围绝经期妇女β-EP水平变化可能会引起神经内分泌功能的紊乱,暂时性地影响更年期妇女的血管舒缩功能,但对血压及血管因子无明显影响.     

瓦沙比对肾性高血压大鼠血浆β-内啡肽浓度的影响

目的:观察瓦沙比对肾性高血压大鼠血浆β-内啡肽(β-EP)浓度的影响.方法:采用左肾动脉狭窄法建立二肾一夹(2K1C)高血压大鼠模型.于术后第 8天分别以20% 瓦沙比、10% 瓦沙比、0.1% 卡托普利、冷开水(模型组 )20 mL/kg灌胃,假手术组灌胃等量冷开水,1次 /d,连续26 d.于第27天断头取血,用放射免疫法测定大鼠血浆β-EP浓度.结果:模型组大鼠血浆β-EP浓度显著增高,与假手术组比较,差异有非常显著性意义(P<0.01); 瓦沙比各组及 0.1% 卡托普利组则可使之降低,与模型组比较,20% 瓦沙比组差异有非常显著性意义(P<0.01),10% 瓦沙比组和 0.1% 卡托普利组差异有显著性意义(P<0.05).结论:瓦沙比在降低高血压大鼠血压的同时,也降低高血压大鼠血浆β-EP浓度,且作用呈剂量依赖性.     

坤宁安对围绝经期综合征大鼠下丘脑β-内啡肽及神经递质的影响

目的探讨坤宁安对β-内啡肽及神经递质的影响,揭示其防治围绝经期综合征的作用机制。方法建立自然围绝经期综合征动物模型,放射免疫法、荧光分光光度法和比色法检测各实验组大鼠下丘脑组织β-内啡肽(β-EP)、5-羟色胺(5-HT)、去甲肾上腺素(NE)和外周血超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、丙二醛(MDA)的变化,光学及电子显微镜观察各组大鼠下丘脑组织结构变化。结果坤宁安浓缩丸能提高围绝经期综合征大鼠下丘脑β-EP、NE含量,降低5-HT水平和5-HT/NE比值,提高围绝经期大鼠血浆中SOD、GSH-PX的活性,降低血清中MDA的含量。各组超微结构变化与以上结果相一致。结论坤宁安浓缩丸通过调节神经—内分泌紊乱状态,改善自由基代谢,维持机体内环境相对稳定。     

孕酮对大鼠吗啡位置偏爱相关脑区中β-内啡肽水平的影响

目的:观察孕酮对吗啡所致奖赏效应及相关脑区中β-内啡肽(β-EP)水平的影响.方法:将40只SD大鼠随机分为生理盐水对照(NS)组、吗啡组、孕酮组和孕酮+吗啡组,上午NS组和孕酮组皮下给予环糊精和孕酮15 mg/kg,10 min后腹腔给予生理盐水5 mg/kg,吗啡组和孕酮+吗啡组皮下给予环糊精和孕酮15 mg/kg,10 min后腹腔给予吗啡5 mg/kg,放入白室训练.下午各组动物均皮下和腹腔给予等量的环糊精和生理盐水,放入黑室训练.建立吗啡条件性位置偏爱(CPP)模型,采用放射免疫法测定大鼠不同脑区中β-EP含量.结果:与NS组比较,吗啡组产生稳定的CPP效应(P<0.01),孕酮和孕酮+吗啡组均未产生CPP效应.与NS组比较,CPP形成时,吗啡组大鼠下丘脑、海马和额叶皮质中β-EP水平显著降低(P<0.05,P<0.01和P<0.05).与吗啡组比较,孕酮+吗啡组大鼠下丘脑中β-EP水平显著升高(P<0.01),而其他脑区内无明显变化(P>0.05).结论:孕酮可有效抑制吗啡CPP效应,其机制可能与逆转吗啡诱导的下丘脑中β-EP水平有关.     

纳洛酮对急性酒精中毒患者血浆β-内啡肽水平的影响

目的观察纳洛酮对急性酒精中毒患者血浆β-内啡肽水平的影响。方法将85例急性酒精中毒患者随机分为2组,对照组42例,采用补液利尿常规治疗;实验组43例,在常规治疗的基础上,采用纳洛酮治疗,比较两组疗效和治疗前后1h、2h血浆β-内啡肽水平。结果实验组的治疗持续时间明显短于对照组(P<0.01),治疗后血浆β-内啡肽水平明显低于对照组(P<0.01)。结论纳洛酮能够降低血浆β-内啡肽的水平,用于治疗急性酒精中毒安全有效。     

Syntheses,opioid binding affinities,and potencies of dynorphin A analogues substituted in positions 1, 6, 7, 8 and 10

Structural, stereochemical, stereoelectronic and conformational requirements for biological activity of dynorphin A_1–11-NH₂ analogues at opioid receptors were explored by substitution of Tyr¹, Arg⁶, Arg⁷, Ile⁸ and Pro¹⁰ with other amino acid residues. Interestingly, substitution of Tyr¹ with N^α-Ac-Tyr^l, D-Tyr¹, Phe¹ or p-BrPhe¹ led to analogues that were quite potent at κ opioid receptors, and additional substitution of Ile⁸with D-Ala⁸ and/or Pro¹⁰ with D-Pro¹⁰ retained high potency in brain binding assay: [N^α-Ac-Tyr¹]- (1), [D-Tyr¹]- (2) [Phe¹]- (3), [Phe¹. D-Ala⁸]- (5), [p-BrPhe¹, D-Ala^s]- (6), [Phe¹, D-Pro¹⁰]- (7) and [Phe¹, D-Ala⁸, D-Pro¹⁰]-Dyn A_1–11-NH₂ (8) had IC₅₀(nM) binding affinities of 13.2, 18.6, 1.64, 1.26, 1.84, 2.44 and 1.62 nM, respectively. The D-Phe¹ analogue 4, however, was only weakly active (610 nM). All of the analogues except 4 were modestly selective for κ vs. μ guinea pig brain opioid receptor (11- to 88–fold) and quite selective for κ vs. δ receptors (65–576). However, all of the analogues appeared to have very low or essentially no activity in the guinea pig ileum and mouse vas deference functional bioassays, and one analogue, 5, appeared to have weak antagonist activities. On the other hand, if constrained amino acids such as β-methylphenylalanine or 1,2,3,4-tetrahydroisoquinoline carboxylic acid, and hydroxyproline were placed in the 1 position, inactive analogues or analogues with greatly reduced potency and biological activity were obtained (compounds 12–14). It had previously been suggested that the Arg⁶ and Arg⁷ residues were critical for biological activity. However, when we replace either one of these residues, [Nle⁶]Dyn A_1–11 (9) and [Nle⁷]Dyn A_1–11-NH₂ (10) were both highly potent binders in κ receptor binding studies (IC₅₀= 0.95 and 0.43 nM, respectively), and interestingly also were potent in μ and δ binding studies. Furthermore, both of the analogues were modestly potent in the GPI and MVD assays (94, 65 nM; 31, 81 nM, respectively). These results demonstrate that basic residues at positions 6 and 7 in dynorphin are not very important for binding to κ opioid receptors. Finally, many of the compounds reported here showed high selectivity for central vs. peripheral κ opioid receptors, with compound 4 being the most selective (63 000-fold).     

强啡肽A（1－17）对大鼠脊髓组织钙调蛋白含量和磷酸二酯酶活性的影响

观察强啡肽Ａ（１－１７）经大鼠蛛网膜下腔注射后对胞内Ｃａ２＋受体钙调蛋白（ＣａＭ）含量及其依赖于Ｃａ２＋／ＣａＭ的磷酸二酯酶（ＰＤＥ）活性的影响。结果表明：强啡肽Ａ（１－１７）１０、２０ｎｍｏｌ给药１０ｍｉｎ可使脊髓组织ＣａＭ含量和ＰＤＥ活性明显下降，呈量效依赖关系，２ｈ后均有不同程度的恢复。选择性ｋ型阿片受体拮抗剂ｎｏｒ－ＢＮＩ３０ｎｍｏｌ、兴奋性氨基酸ＮＭＤＡ受体特异性拮抗剂ＡＰＶ１０ｎｍｏｌ可显著对抗强啡肽Ａ（１－１７）２０ｎｍｏｌ降低脊髓组织ＣａＭ含量的作用并完全阻断强啡肽Ａ（１－１７）对ＰＤＥ活性的抑制；Ｌ型Ｃａ２＋通道阻断剂异搏定１００ｎｍｏｌ亦可部分阻断强啡肽Ａ（１－１７）２０ｎｍｏｌ对脊髓组织ＣａＭ含量和ＰＤＥ活性的影响。     

强啡肽A_(1～13)对谷氨酸诱导的大鼠星形胶质细胞肿胀的影响

目的　建立谷氨酸诱导的大鼠星形胶质细胞肿胀模型,观察 Ｄｙｎ Ａ１ ～１３ 对谷氨酸诱导的大鼠星形胶质细胞肿胀的影响。方法　［３ Ｈ］ ３ 氧甲基 Ｄ 葡萄糖摄取测定细胞含水量。结果　①给予０５ ,１０ ,１００ ｍ ｍｏｌ· Ｌ－ １ 的谷氨酸作用１ ｈ 均可引起细胞的含水量增加。②强啡肽 Ａ（ Ｄｙｎ Ａ） 可降低谷氨酸诱导肿胀的大鼠星形胶质细胞含水量。③κ受体拮抗剂ｎｏｒ Ｂ Ｎ Ｉ可阻断 Ｄｙｎ Ａ１ ～１３ 降低谷氨酸诱导的肿胀大鼠星形胶质细胞含水量的作用。结论　谷氨酸可诱导大鼠星形胶质细胞肿胀; Ｄｙｎ Ａ１ ～１３ 可通过激活κ受体抑制谷氨酸诱导的大鼠星形胶质细胞肿胀     

赛拉嗪对小鼠胃肠运动及大鼠胃肠电的影响

育亨宾(0.5～4mg·kg~(-1),sc)和苯口恶咪唑(2～8 mg·kg~(-1).sc)剂量依赖性地拮抗赛拉嗪(4mg·kg~(-1),sc)对小鼠胃肠推进运动的抑制作用.赛拉嗪(2、4 mg·kg~(-1),sc)可乐定(120μg·kg~(-1),sc)抑制大鼠胃、十二指肠、空肠、回肠的肌电活动,用药后30min作用最显著。育亨宾(4 mg·kg~(-1),sc)一定程度地拮抗赛拉嗪(4 mg·kg~(-1),sc)抑制胃肠肌电活动的作用.     

Role of tryptophan-14 in the interaction of dynorphin A(1-17) with micelles

Fluorescence spectroscopy has been used to examine the interaction between the opioid peptide dynorphin A(1-17) (dynorphin) and dodecylphosphocholine (DPC) micelles. Fluorescence emission spectra as a function of added lipid indicate insertion of the Trp¹⁴ side chain into the hydrophobic portion of the micelle, supporting NMR results from this laboratory. A model of interaction with micelles consistent with the fluorescence results and earlier NMR results is proposed. The critical micelle concentration in the presence of peptide was also determined, and is discussed in the context of relevance to both NMR spectroscopy and peptide-lipid interactions. © Munksgaard 1997.     

Stimulation of food intake in rats by the alpha 2-adrenoceptor agonists xylazine and detomidine

Effects of the alpha 2-adrenoceptor agonists xylazine and detomidine on food intake in freely feeding male rats were evaluated. Intraperitoneal (i.p.) injection of xylazine (0.25-3 mg/kg) and detomidine (25 and 50 micrograms/kg) significantly increased the 2 and 24 h food intake from control values. Treatment of rats with the alpha 2-adrenoceptor antagonist yohimbine (1 mg/kg, i.p.) 15 min before xylazine (0.5 mg/kg, i.p.) or detomidine (50 micrograms/kg, i.p.) significantly inhibited the increase in food intake. Yohimbine treatments alone at 0.5, 1 and 2 mg/kg, i.p. did not significantly change the 2 and 24 h food intake from control values. The results suggest that the alpha 2-agonists xylazine and detomidine enhance food intake in rats.     

Serotonergic regulation of the brain and gut beta-endorphin and dynorphin content in the rat

A specific radioimmunoassay was used to measure immunoreactive dynorphin (ir-DYN) and beta-endorphin (ir-BE) in the brain, pituitary and gut, following a pharmacological manipulation of the serotonin system. Administration of the serotonin receptor agonist m-chlorophenylpiperazine (m-CPP, 2.5-5 mg/kg ip) or the serotonin releasing agent fenfluramine (20-40 mg/kg ip) induced a significant increase in the hypothalamic ir-BE content and a decrease in its anterior pituitary level. These effects were antagonized by cyproheptadine (1 mg/kg ip). Similar results were obtained after fluvoxamine (15 mg/kg ip), femoxetine (10 mg/kg ip) and 5-hydroxytryptophan (5-HTP 40-160 mg/kg ip). None of the above treatments altered significantly the ir-DYN content in the brain and pituitary. However, the gut ir-DYN level was dramatically decreased after m-CPP, fenfluramine, fluvoxamine, femoxetine and 5-HTP. The latter effect was antagonized by cyproheptadine. The obtained results suggest that serotonergic activation stimulates the release of beta-endorphin from the anterior pituitary and dynorphin from the gut, while the cerebral beta-endorphin system appears to be inhibited by activation of serotonin neurons.     

Naloxone produces hypothermia in rats pretreated with beta-endorphin and morphine

The effects of naloxone (an antagonist of opioids at opiate receptors) on the thermoregulatory responses were assessed in three groups of naive (saline-treated), morphine-tolerant (24 hr after a dose of 100 mg/kg (s.c.) of morphine-oil suspension or three doses of 100 mg/kg (i.p.) of morphine and beta-endorphin-tolerant (24 hr after an intraventricular dose of 100 μg of beta-endorphin) rats at an ambient temperature of 22°C. Both morphine and beta-endorphin produced hypothermia, catatonia and sedation in naive rats. The hypothermia was due to decreased metabolic rate and cutaneous vasodilation. However, both in morphine-tolerant and beta-endorphin-tolerant rats, morphine and betaendorphin each produced hyperthermia rather than hypothermia. There were no changes in behavior. The hyperthermia was due to increased metabolism. Furthermore, naloxone administration produced a dose-dependent hypothermia and abstinence syndrome in both morphine-tolerant and beta-endorphin-tolerant rats, but not in naive rats. The hypothermia in response to naloxone in opioid-tolerant rats was brought about by both decreased metabolism and cutaneous vasodilatation. The data indicate that pretreatment of rats with opioids alters the thermoregulatory effects of naloxone.     

噻拉嗪对小鼠大鼠抗缺氧的实验研究

采用常压缺氧，窒息性缺氧，组织缺氧等方法观察噻拉嗪对小鼠、大鼠缺氧的保护作用。结果表明，不同剂量的噻拉嗪均能延长小鼠常压缺氧的生存时间，降低耗氧量，提高动物对缺氧环境的耐受力，呈剂量依赖性关系。尤以噻拉嗪ｉｃｖ作用显著，并为α２受体拮抗剂苯恶唑阻断。此外噻拉嗪明显降低氰化钾中毒小鼠的死亡率，提高窒息性缺氧大鼠的氧分压，延长窒息性缺氧小鼠心电消失时间。     

Stabilized dynorphin derivatives for modulating antinociceptive activity in morphine tolerant rats: Effect of different routes of administration

Dynorphins, such as dynorphin A(1-13) (Dyn A(1-13)), have been shown to enhance analgesia in morphine-tolerant animals, despite their very short half-life after intravenous administration. The potential use of dynorphins in humans is therefore of interest. This laboratory has recently evaluated the metabolic fate of stabilized dynorphin derivatives. This study was conducted to evaluate whether such stabilized derivatives, ie, [N-Met-Tyr1]-Dynorphin A(1-13) (N-MT Dyn A, stabilized at the N-terminal end) and [N-Met-Tyr1]-Dynorphin A(1-13) amide (N-MT Dyn A amide, stabilized at the C- and N-terminal ends), would enhance the antinociceptive activity of morphine not only after intravenous administration but also after subcutaneous and pulmonary delivery. Intravenous administration of N-MT Dyn A (5 micromol/kg) and N-MT Dyn A amide (5 micromol/kg) to morphine-tolerant rats resulted in significantly higher tail-flick latencies than those observed for the saline group. These effects could be observed for up to 2.0 +/- 0.1 hours after intravenous administration of N-MT Dyn A and for up to 3.4 +/- 1.4 hours for N-MT Dyn A amide. The time-averaged effects of both peptides were similar. After pulmonary delivery of the same dose, derivatives remained active. The duration of the effects after pulmonary administration of the amide was 4.4 +/- 2.5 hours while that of N-MT Dyn A was slightly shorter (2.8 +/- 0.9 hours). No effect was observed after subcutaneous administration of N-MT Dyn A. These results suggest that pulmonary delivery of stabilized dynorphin derivatives represents a possible alternative to intravenous administration.