IL-1对冷应激大鼠睾丸间质细胞睾酮浓度的调节

目的观察白细胞介素-1(IL-1)对冷应激大鼠睾丸间质细胞(Leydig)睾酮浓度的影响。方法将大鼠随机分为对照组与冷应激组,分离培养睾酮Leydig细胞。利用冰箱进行冷应激处理,采用放射免疫分析法测定睾酮和cAMP及IL-1。结果(1)IL-1对Leydig细胞培养24 h睾酮生成量的影响:实验组为(1 821.7±99.7)fmol.mL-1,明显高于对照组(984.1±104.8)fmol.mL-1(P<0.01);(2)IL-1对冷应激Leydig细胞培养24 h睾酮生成量的影响:实验组为(212.4±123.7)fmol.mL-1,明显低于对照组(398.4±112.6)fmol.mL-1(P<0.01);(3)IL-1对冷应激Leydig细胞培养24 h时cAMP生成量的影响:实验组为(0.202±0.042)pmol.mL-1,明显低于对照组(0.368±0.017)pmol.mL-1P<0.01。结论IL-1单独作用能促进Leydig细胞睾酮分泌,IL-1对睾酮合成的影响与cAMP系统有关。     

哮喘患儿cAMP/cGMP平衡的研究及心先安对其的调节作用

【目的】探讨支气管哮喘患儿血浆环磷酸腺苷(cAMP)/磷酸鸟苷(cGMP)比值变化及其临床意义,以及心先安治疗支气管哮喘的疗效。【方法】①采用特异性放射免疫分析法检测22例哮喘患儿急性期和缓解期外周血浆cAMP、cGMP表达水平,并以24例正常儿童作对照。②采用特异性放射免疫分析法检测接受常规治疗和心先安治疗(每次2.5~5.0 mg/kg,每日1~2次,连续7 d)的19例哮喘患儿外周血浆cAMP、cGMP表达水平,以接受常规治疗的22例哮喘患儿作对照。【结果】①哮喘患儿急性期外周血浆cGMP水平高于缓解期和正常组(P<0.05),而cAMP水平和cAMP/cGMP水平低于缓解期和正常组(P<0.05);②予心先安治疗的哮喘患儿外周血浆cAMP水平和cAMP/cGMP水平高于对照组(P<0.05),而cGMP水平低于对照组(P<0.05)。【结论】①哮喘患儿cGMP表达亢进,cAMP表达不足。cAMP/cGMP平衡失调,可作为监测和指导哮喘治疗的生化指标;②哮喘患儿给予心先安治疗能够纠正cAMP/cGMP失衡,疗效较好。     

冷应激对人绒毛膜促性腺激素诱导大鼠黄体与颗粒细胞功能的影响

目的为探讨冷应激对大鼠卵巢功能的影响。方法采用体外细胞培养法分离培养大鼠卵巢黄体、颗粒与卵母细胞,设37℃对照组与0、-5、-10、-15、-20、-25℃冷应激组,观察人绒毛膜促性腺激素(hCG)诱导黄体与颗粒细胞分泌孕酮与cAMP的变化,采用放免分析方法测定孕酮与cAMP生成含量,采用四甲基偶氮唑蓝(MTT)法检测细胞存活率。结果-5～-25℃冷应激组黄体细胞和颗粒细胞孕酮含量均低于对照组(均P<0.05),与对照组比较,冷应激组黄体细胞基础cAMP生成量增加,除-20℃组外,差异均有统计学意义(均P<0.05);与对照组比较,除-10℃冷应激组颗粒细胞基础cAMP生成量下降外,其余各组均升高,且差异有统计学意义(P<0.05)。0～-25℃冷应激组细胞存活抑制率呈上升趋势。结论冷应激抑制hCG诱导黄体与颗粒细胞孕酮分泌,协同cAMP生成,使卵母细胞存活率下降,其作用机制有待深入研究。     

慢性氟中毒大鼠骨组织中AC-cAMP-PKA信号转导通路的表达

目的观察慢性氟中毒大鼠骨组织中AC、cAMP、PKA的表达。方法将48只断乳2周的Wistar大鼠按体重随机分为4组,分别为对照组(自来水)和低剂量组(含50 mg/L NaF自来水)、中剂量组(含150mg/L NaF自来水)、高剂量组(含250 mg/L NaF自来水),每组12只,雌雄各半。采用自由饮用的方式进行染毒,连续染毒6个月。检测大鼠尿氟、骨氟浓度及氟斑牙发生率以及骨组织中AC、cAMP、PKA的水平。结果与对照组比较,各剂量染毒组大鼠尿氟、牙氟及骨氟浓度均较高(P<0.05),斑牙检出率随染毒时间延长而增高,随染毒剂量的增加氟斑牙程度越严重;而各组骨组织中AC、cAMP、PKA含量差异无统计学意义(P>0.05)。结论在本次实验中未观察到氟化钠引起大鼠骨组织AC、cAMP含量的改变。     

碘缺乏对大鼠仔鼠海马蛋白激酶C活性的影响

目的研究碘缺乏、甲状腺功能减退对仔鼠海马蛋白激酶C(PKC)活性的影响。方法分别选用低碘饲料及他巴唑诱导建立低碘及甲减大鼠动物模型,在生后第30 d时收集低碘组、甲状腺功能减退组及对照组大鼠仔鼠海马组织,测定海马细胞浆、细胞膜PKC活性。结果生后30 d低碘组和甲状腺功能减退组仔鼠海马胞液PKC活性(24.876 3±13.731 9),(26.342 0±7.302 8)pmol/(min.mg)略低于对照组(36.775 8±15.711 3)pmol/(min.mg);而胞膜PKC活性(33.220 7±18.341 4),(30.177 5±10.443 3)稍高于对照组(20.559 8±6.312 1)pmol/(min.mg),低碘组、甲状腺功能减退组仔鼠海马胞膜PKC活性与胞浆PKC活性比值(1.187 1±0.432 5),(1.414 3±0.394 0)较对照组升高(0.649 3±0.294 3),差异有统计学意义(P<0.01)。结论低碘、甲状腺功能减退可引起仔鼠海马胞浆PKC向胞膜的转运,可能是低碘、甲减引起海马损害导致学习记忆功能减退的机制之一。     

肿瘤坏死因子-α对肺成纤维细胞内第二信使物质含量的影响

目的观察不同浓度的肿瘤坏死因子-α(TNF-α)作用于大鼠肺成纤维细胞不同的时间对细胞内信号物质三磷酸肌醇(IP3)、环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)的影响.从而探讨由G蛋白介导的TNF-α致肺纤维化信号通路.方法应用细胞培养技术对SD大鼠的乳鼠肺成纤维细胞进行原代培养,传至4～5代后,用不同浓度的TNF-α刺激培养不同的时间,用放射免疫技术测定细胞内IP3、cAMP、cGMP的含量.结果①不同时间cAMP、cGMP、cAMP/cGMP并不随着TNF-α作用浓度增加呈现规律性变化;②在60、120 s时,随着TNF-α剂量的增加IP3的每分钟放射活性(cpm)逐渐上升.对照组、5 μg/L组、20 μg/L组IP3cpm值随着作用时间的延长逐渐增大.结论在一定的作用时间,一定的作用剂量范围内,TNF-α可以引起肺成纤维细胞内第二信使物质IP3、cAMP、cGMP含量的变化.     

急性和重复性心理应激大鼠某些细胞免疫功能的变化

目的 探讨急性和重复性心理应激对大鼠某些细胞免疫功能的影响.方法 将60只Sprague-dawley(SD)大鼠随机分为6组,每组10只,3个应激组分别接受为期1、14和28 d束缚应激(6 h/d),相应的3个对照组不接受任何应激处理.分别测定大鼠在应激和非应激状态下脾自然杀伤(NK)细胞活力和T淋巴细胞增殖活力.结果 反复应激束缚14和28 d组大鼠的脾质量[14 d:(623.75±62.10)mg vs (985.98±127.79)mg,28 d:(672.50±49.82)mg vs(1 055.75±94.96)mg]、脾指数[14 d:(0.20±0.01) vs (0.27±0.02),28 d:(0.19±0.01) vs (0.27±0.02)]、胸腺质量[14 d:(319.88±76.30)mg vs (512.25±106.06)mg,28 d:(312.75±48.00)mg vs(488.13±34.56)mg]及胸腺指数[14d:(0.10±0.02)vs(0.15±0.03),28 d:(0.09±0.01)vs(0.13±0.02)]均低于相应的对照组大鼠,同时,反复应激组大鼠的脾脏T淋巴细胞增殖功能[(14 d时ConA 5 mg/L:(57 587.75±9 958.97)cpm vs(154 919.88±4 961.22)cpm,14 d时ConA 2.5 mg/L:(52 323.50±530.71)cpm vs(102 047.63±3 329.69)cpm;28 d时ConA 5.0 mg/L:(52 350.00±2 500.89)cpm vs(153 460.88±11 971.49)cpm,28 d时ConA 2.5 mg/L:(42 322.38±403.85)cpm vs(100 068.63±11 326.51)cpm]及脾脏NK细胞的活力也低于相应的对照组大鼠;而急性应激束缚1 d组大鼠的各项指标与对照组相比无明显差异.结论 反复应激刺激对大鼠的某些细胞免疫功能具有抑制效应.     

甲胺磷和乙酰甲胺磷对大鼠脑组织内游离钙及环腺苷酸的影响

目的　研究高毒有机磷化合物甲胺磷与其替代品乙酰甲胺磷对大鼠脑组织内游离钙[Ca2 ]i及环腺苷酸 (cAMP)的影响。方法　SD大鼠随机分为 2个染毒组与对照组 ,染毒组连续 5d分别腹腔注射 1 2 0LD50 甲胺磷和乙酰甲胺磷 ;以Fura - 2 AM为荧光指示剂 ,RF - 5 30 1PC荧光分光光度计测定大鼠神经细胞 [Ca2 ]i浓度的变化 ;FJ - 2 0 0 3 2 0 0γ免疫计数器测定大鼠脑组织cAMP含量。结果　甲胺磷染毒组大鼠皮层及海马细胞 [Ca2 ]i分别为 (32 3.86± 2 3.6 0 )、(2 80 .79± 2 1.92 )nmol L ;乙酰甲胺磷染毒组大鼠皮层及海马细胞 [Ca2 ]i分别为 (2 2 5 .2 4± 19.86 )、(2 17.84± 11.0 3)nmol L。甲胺磷组大鼠皮层及海马 [Ca2 ]i高于对照组 [(2 0 9.82± 10 .73)、(199.0 1± 17.17)nmol L],差异有显著性 (P <0 .0 1)。甲胺磷染毒组大鼠皮层及海马cAMP含量为 (35 .2 4± 7.6 3)、(75 .36± 11.31)pmol mg;乙酰甲胺磷染毒组大鼠皮层及海马cAMP含量为 (30 .75± 5 .76 )、(6 9.5 7± 12 .5 9)pmol mg,两者与对照组 [(2 9.4 3± 4 .73)、(6 0 .99± 7.4 1)pmol mg]的差异均无显著性 (P >0 .0 5 )。结论　甲胺磷和乙酰甲胺磷对第二信使影响存在差异 ,可能是两者最终神经毒性作用不同的原因之一。     

亚急性乐果染毒对自发性高血压大鼠心血管系统的影响

[目的]观察14d乐果染毒对自发性高血压大鼠(SHR)心血管系统的影响,探讨钙离子稳态在该影响中的作用。[方法]雄性SHR,灌胃染毒,染毒剂量分别为0、12.5、25和50mg/kg,每天1次,连续14d。尾袖法测定大鼠血压,第15天处死动物,无机磷酸根法和RT-PCR检测酶活力和基因表达。[结果]25mg/kg以下乐果染毒大鼠血压升高,当剂量达到50mg/kg,大鼠血压没有显著升高的变化。染毒结束后,25mg/kg染毒组大鼠心肌Ca2 -ATPase活力显著升高,达到(2.32±0.33)μmolPi/(mg蛋白·h);50mg/kg组大鼠心肌Ca2 ATPase活力和Na -K -ATPase均显著升高,分别为(2.36±0.62)和(2.74±0.52)μmolPi/(mg蛋白·h)。Ca2 -ATPase基因表达随染毒剂量的增加而逐渐上调,剂量>25mg/kg时,表达值为(1.24±0.11),差异有显著性(P<0.05);50mg/kg乐果可诱导兰尼碱受体(RyR)的mRNA表达显著高于对照组(P<0.05),表达值分别为(1.49±0.27)和(0.96±0.16)。[结论]乐果引起自发性高血压大鼠血压的变化规律与接触剂量有关,一定剂量范围的可以升高。钙离子的代谢紊乱可能是乐果引起的心血管毒作用的机制之一。     

急性和重复性心理应激对大鼠血清皮质酮和免疫组织中糖皮质激素受体的影响

目的探讨急性和重复性心理应激对大鼠血清皮质酮和免疫组织中糖皮质激素受体(GR)的影响。方法60只SD大鼠分为6组,3组分别接受为期1、14和28 d束缚应激(6 h/d),相应的3个对照组大鼠不接受任何应激处理。分别测定大鼠在应激和非应激状态下血清皮质酮水平以及胸腺组织和脾淋巴细胞中GR的水平。结果3个对照组大鼠的血清皮质酮水平分别为(103.4±6.4)、(100.0±7.8)和(99.2±11.2)ng/L血清,应激状态下则分别为(624.6±52.0)、(663.1±48.1)和(673.6±26.9)ng/L血清。14和28 d应激组大鼠的胸腺GR数目均明显低于相应的对照组动物[(38.36±2.71)vs(24.48±2.00)pmol/g蛋白,(39.11±4.13)vs(23.66±2.63)pmol/g蛋白];1、14和28 d应激组大鼠脾淋巴细胞中的GR数目亦明显低于相应的对照组动物[(5 189.88±180.11)vs(4 816.88±197.72)结合位点/细胞,(5 822.38±179.27)vs(2 990.13±120.67)结合位点/细胞,(5 887.38±108.83)vs(1 820.50±161.11)结合位点/细胞]。结论急性和重复性心理应激可以增强糖皮质激素(GC)的分泌,同时下调免疫组织中的GR水平,对动物机体造成病理性应激损伤。     

维生素E对冷暴露大鼠尿中环核苷酸含量的影响

本研究旨在探讨维生素E是否对冷暴露大鼠环核苷酸代谢有影响。我们采用了放射免疫法测定4℃下大鼠口服维生E后尿中环核管酸含量。结果表明:冷暴露大鼠尿中环核苷酸排泄持续增加,而cAMP/cGMP比值未见改变。维生素E增加冷暴露大鼠cAMP排泄,与单纯冷暴露组对比,P<0.025。cGMP排泄相差不显著。冷暴二周后提高了cAMP/cGMP比值,P<0.025。提示维生素E可能提高以cAMP为“第二信使”的低温环境下的能量代谢。     

葡萄糖酸锌对肿瘤患者 DNCB 皮肤试验及血浆 cAMP cGMP 水平的影响

观察了１７例肿瘤患者口服葡萄糖酸锌后血浆ｃＡＭＰ、ｃＧＭＰ水平及ＤＮＣＢ皮肤反应的变化。结果显示，服药后血浆ｃＡＭＰ水平及ｃＡＭＰ／ｃＧＭＰ比值升高；ＤＮＣＢ皮肤反应较对照组增强。表明葡萄糖酸锌能调节肿瘤患者血浆环核苷酸水平，并能显著提高细胞免疫功能。     

冷暴露对大鼠黄体细胞与颗粒细胞功能的影响

目的探讨不同冷强度多次冷暴露对大鼠卵巢功能的影响。方法采用体外细胞培养法分离培养大鼠卵巢黄体、颗粒细胞,设37℃对照组与4、0℃冷暴露组,观察人绒毛膜促性腺激素(hCG)诱导黄体与颗粒细胞分泌孕酮及环磷酸腺苷(cAMP)的变化,采用放免分析方法测定孕酮与cAMP生成含量。结果与对照组比较,4℃重复3次冷暴露,黄体细胞与颗粒细胞的孕酮和cAMP生成量呈升高趋势,cAMP升高显著(P0.01);0℃第1次冷暴露,孕酮和cAMP生成量升高,cAMP升高显著(P0.01);第2次和第3次冷暴露,均显著下降(P0.05,P0.01)。结论冷暴露强度、次数对大鼠卵巢黄体细胞与颗粒细胞分泌孕酮及cAMP功能有影响。     

维生素E对冷暴露大鼠环核苷酸含量的影响

采用放射免疫分析法测定０～２℃下大鼠补充维生素Ｅ后血及肝脏组织中环核苷酸含量，探讨维生素Ｅ提高机体耐寒力的机理。结果表明：单纯冷暴露组大鼠血及肝脏组织中环核苷酸含量持续增高；冷暴露同时给维生素Ｅ组大鼠体内环核苷酸含量与对照组相比增高不明显，提示：维生素Ｅ可通过影响冷暴露大鼠体内环核苷酸代谢，以促进机体对寒冷的适应，提高机体的耐寒力。     

Effects of a protein-free diet on the changes in cyclic AMP and cyclic GMP levels induced by immunization in splenic T and B lymphocytes in the rat.

The levels of cyclic nucleotides, cAMP and cGMP, were determined in splenic lymphocytes of normally fed (N) and protein deprived (PD) rats before and at different time intervals after a single injection of sheep erythrocytes. Assays were performed with protein binding methods on unseparated as well as on T and B cells fractionated by filtration through nylon wool. The cAMP levels increased in unfractionated cells and in T and B lymphocytes 2 hours following immunization of N rats. Another rise in cAMP levels occurred after 3 days in B lymphocytes, but there was also a simultaneous increase of the cGMP levels in preparations of unfractionated cells and in B lymphocytes. The PD diet suppressed or delayed most of the aforementioned changes. Thus, the immunodepressive effect of such a diet may be ascribed to the inhibition of both the early signal (increase of cAMP levels and of cAMP/cGMP ratio) leading to T and B differentiation and the later signal (increase of cGMP levels) which initiates antibody production.     

Induction of implantation in the rat by cyclic nucleotides

Implantation in the rat is preceded by a surge of estrogen which appears essential to the decidual izati on process. Moreover, the levels of cAMP and cGMP in rat uterus show characteristic reciprocal fluctuations following estrogen treatment. Recently, cAMP has been shown to induce implantation in the mouse. In the present study, cyclic nucleotides are shown to be involved in the initiation of implantation in the rat. Alloxan, an inhibitor of cAMP synthesis, effectively blocked implantation. Simultaneous administration of cGMP prevented the alloxan block. Administration of cAMP, cGMP or theophylline, facilitated implantation in rats in a state of simulated delayed implantation. The present study is the first demonstration of the importance of cyclic nucleotides in implantation in the rat, and the first indication of an essential role for cGMP.     

Cyclic AMP and GMP levels in thymocytes and splenic T and B lymphocytes in protein deprived rats.

Cyclic nucleotide levels were determined in thymocytes and in splenic T and B lymphocytes separated by nylon wool filtration. In control rats, thymocytes contained less cAMP and cGMP than splenic T cells. The level of cGMP was lower, and consequently cAMP:cGMP ratio was higher in splenic B than in T cells. Protein deprivation increased the nucleotide ratios in both T and B splenic lymphocytes; this effects was due to a decrease in the cGMP levels in the case of the T cells and to an increase in the cAMP levels in the B cells. These data could be related to the reduced mitotic activity of the splenic lymphocytes. However, the nylon-nonadherent thmyocytes of protein deprived rats paradoxically displayed increased cGMP contents without changes in the cAMP levels, despite the drop in their proliferative potential. The impairment of cyclic nucleotide metabolism may intervene in the immunological disturbances due to protein malnutrition.     

Cyclic 3′, 5′-adenosine monophosphate and cyclic 3′, 5′-guanosine monophosphate metabolism in malnutrition

When the concentration and turnover of the cyclic nucleotides cyclic 3′, 5′-adenosine monophosphate (cAMP) and cyclic 3′,5′-guanosine monophosphate (cGMP) were measured in the thymus, spleen and cervical lymphnodes of xats subjected to various models of malnutrition, and these same parameters of cAMP alone assessed in their liver, kidney and brain, undernutrition has been found to modify cyclic nucleotide metabolism. When the results on nucleic acid and protein metabolism are taken into consideration with the changes in cyclic nucleotide metabolism, it was noted that the various phases of the cell cycle are prolonged or blocked in the organs of malnourished rats. These data indicate a correlation between cyclic nucleotide metabolism and impaired immune responsiveness seen commonly in undernourished rats.     

Pancreatic exocrine function and cyclic nucleotides in the diabetic rat.

Streptozotocin-induced diabetes mellitus in the rat results in a 30% decrease in serum amylase and an 80% decrease in pancreatic amylase levels. Pancreatic trypsinogen levels decrease 50% whereas pancreatic lipase levels increase 30%. Plasma cyclic nucleotide levels (cAMP and cGMP) increase 40-100%, urine cyclic nucleotide levels decrease 75-99%, but pancreatic cyclic nucleotide levels are unchanged. Short-term insulin treatment restores pancreatic amylase and trypsinogen levels to normal but has no effect on serum amylase or pancreatic lipase levels. Plasma cAMP levels decrease 20% toward normal during insulin treatment, but no other effects on cyclic nucleotide levels occur. These data confirm the profound but reversible effect of experimental diabetes mellitus on pancreatic secretion of amylase and trypsinogen. The results suggest that cyclic nucleotides do not play a direct role in the generation of pancreatic exocrine deficiency in diabetes mellitus or its reversal by insulin.     

Pancreatic exocrine function and cyclic nucleotides in the diabetic rat

Streptozotocin-induced diabetes mellitus in the rat results in a 30% decrease in serum amylase and an 80% decrease in pancreatic amylase levels. Pancreatic trypsinogen levels decrease 50% whereas pancreatic lipase levels increase 30%. Plasma cyclic nucleotide levels (cAMP and cGMP) increase 40-100%, urine cyclic nucleotide levels decrease 75-99%, but pancreatic cyclic nucleotide levels are unchanged. Short-term insulin treatment restores pancreatic amylase and trypsinogen levels to normal but has no effect on serum amylase or pancreatic lipase levels. Plasma cAMP levels decrease 20% toward normal during insulin treatment, but no other effects on cyclic nucleotide levels occur. These data confirm the profound but reversible effect of experimental diabetes mellitus on pancreatic secretion of amylase and trypsinogen. The results suggest that cyclic nucleotides do not play a direct role in the generation of pancreatic exocrine deficiency in diabetes mellitus or its reversal by insulin.