锌对热应激大鼠垂体POMC mRNA表达的影响

目的：通过锌对热应激大鼠垂体阿黑皮素原（ＰＯＭＣ）ｍＲＮＡ表达的影响研究，探讨锌对热应激大鼠的保护机理。方法：２０只ＳＤ雄性大鼠随机等分４组，即高锌高温暴露组（Ａ组）、中锌高温暴露组（Ｂ组）、低锌高温暴露组（Ｃ组）和正常锌室温对照组（Ｄ组）。在ＡＩＮ－９３Ｍ饲料配方基础上，以碳酸锌为锌源，配制成高锌、中锌、低锌和正常锌饲料，每公斤饲料锌含量测定值分别为９２．２ｍｇ、４５．６１ｍｇ、２１．７０ｍｇ和４５．６１ｍｇ。４组大鼠在室温下饲以相应饲料１４天后，将Ａ、Ｂ、Ｃ组大鼠置于高温室（Ｔｄｂ４０℃，Ｔｗｂ３０．８℃）中连续暴露３小时。用Ｎｏｒｔｈｅｒｎｂｌｏｔ杂交分析法（探针为地高锌标记的ＰＯＭＣｃＲＮＡ），观察垂体ＰＯＭＣｍＲＮＡ表达水平。结果：（１）高温应激可使大鼠垂体ＰＯＭＣｍＲＮＡ表达水平增高；（２）高锌摄入可使热应激大鼠垂体ＰＯＭ－ＣｍＲＮＡ表达水平升高，而低锌摄入则相反。结论：锌对热应激大鼠垂体ＰＯＭＣ基因有调控作用。

A COMPARATIVE STUDY ON HYPOTHALAMIC MECHANISMS OF ANALGESIA INDUCED BY FOUR KINDS OF ACUPUNCTURE THERAPIES IN ADJUVANT ARTHRITIS RATS

Objective: To compare the mechanisms of analgesia induced by four kinds of acupuncture therapies at the hypothalamic level in adjuvant arthritic rats. Methods: Forty-eight SD rats were randomized into normal, model, electroacupuncture (EA), filiform needle (FN), pricking blood-letting (BL) and point injection (PI) groups, with 8 cases in each. EA (20-100 Hz, 2-4 V and duration of 20 min), FN, BL PI were respectively applied to “Kunlun” (昆仑BL 60). Arthritis model was established by injecting complete Freund’s adjuvant (0.1 mL) into the rat’s right foot pad. Behavioral reactions, pain threshold (latency of tail flick to heat stimulation) and local swelling severity (foot volume) were detected; the contents of β-endorphin (β-EP) and adrenocorticotropin (ACTH) were assayed with radioimmunoassay; and the expression of pro-opi-omelanocortin (POMC) mRNA in hypothalamus were determined with hybridization method. Results: The pain threshold was significantly enhanced by all the four kinds of acupuncture therapies, and the effects of EA and PI were more obvious (P<0.05, P<0.01). The severity of local swelling was markedly alleviated by all the four kinds of acupuncture therapies (P<0.01) without significant differences among them (P>0.05). The content of β-EP in the hypothalamus was obviously elevated by EA and FN (P<0.05, P<0.01), and the effect of EA was more obvious, but no marked effect of BL or PI on β-EP was found (P>0.05). The content of ACTH in hypothalamus was considerably elevated by PI (P<0.05), but not by the other three therapies. The expression of POMCmRNA in hypothalamus was significantly strengthened by EA and FN (P<0.01), but not by the other two therapies. Conclusion: EA, filiform needle, blood-letting and point-injection all can produce analgesic effect in adjuvant arthritis rats, the effect of EA and filiform needle may be related to their resultant increase of hypothalamic β-EP, and that of point-injection related to the increase of hypothalamic ACTH level.

前体基因阿片促黑素原基因在功能性肾上腺瘤旁组织中的表达及其意义

目的 检测肾上腺内前体基因阿片促黑素原(POMC)基因编码促肾上腺皮质激素(ACTH)的序列在功能性肾上腺瘤周围组织中的表达。方法 检测3 5例皮质醇瘤、3 1例原醛瘤瘤组织和瘤旁组织ACTH的表达,逆转录 聚合酶链反应(RT PCR)半定量检测编码ACTH的POMC基因的表达量,并测定其序列与Genebank中该基因进行同源性比较分析。结果 肾上腺皮质醇瘤瘤旁组织和瘤组织ACTH表达率分别为91.4%和17.1% ,肾上腺原醛瘤瘤旁组织和瘤组织ACTH表达率分别为90 .3 %和16.1% ,差异有统计学意义(P <0 .0 5 ) ;其前体基因POMCmRNA在皮质醇瘤周围和瘤组织表达分别为1.0 2±0 .10和0 .76±0 .0 3 ,原醛瘤瘤旁组织与瘤组织表达分别为0 .83±0 .0 6和0 .3 5±0 .0 1,差异有统计学意义(P <0 .0 5 ) ;肾上腺内编码ACTH的POMC基因序列与Genebank中完全相同。