GH调控鸡原代肝细胞中GH/IGF-Ⅰ信号通路相关基因mRNA表达的研究

为研究离体条件下鸡肝脏中表达的GH/IGF-Ⅰ信号通路相关基因受生长激素(GH)调控的mRNA表达情况,以4～5周龄雌性商品代AA肉鸡为试验材料,采用改良的半原位两步灌流法并结合消化法分离肝细胞,进行原代培养;采用SYBR green荧光定量PCR方法,检测GH处理后鸡肝细胞中GH/IGF-Ⅰ信号通路中相关基因IGF-Ⅰ、HNF-1α、HNF-1β、HNF-3β、CIS、SOCS-1、SOCS-2和SOCS-3的表达情况。结果表明:胶原酶消化法获得的肝细胞分离良好,形态完整,铺板4h后完全贴壁,继续培养24h即可用于GH处理试验;GH能引起鸡肝细胞中IGF-Ⅰ、SOCS-2、SOCS-3和CIS基因mRNA表达上调,而对HNF-1α、HNF-1β、HNF-3β、SOCS-1基因mRNA的表达无影响。

大鼠甲状旁腺素对体外培养心室肌细胞的促肥大作用

目的观察不同浓度大鼠甲状旁腺素1-34(rat parathyroid hormone 1-34,rPTH1-34)对体外培养心室肌细胞的致肥大作用,观察细胞外信号调节激酶1/2(extracellular signal regulated kinases 1/2,ERK1/2)的变化。方法体外培养新生大鼠心室肌细胞,以1×10-8～1×10-6mol/L rPTH1-34分别孵育24 h,测定细胞直径、3H-亮氨酸(3H-Leu)掺入率、心房钠尿肽(atrial natriuretic peptide,ANP)mRNA、ERK1/2、磷酸化ERK1/2(p-ERK1/2)蛋白的表达。结果与正常组相比,1×10-8mol/L rPTH1-34可使体外培养的心肌细胞直径、细胞蛋白合成速率轻度增加,ANPmRNA表达轻度升高,但无统计学意义;1×10-7,1×10-6mol/L rPTH1-34均可显著增加心肌细胞直径(P<0.01),细胞蛋白合成速率(P<0.01)和ANP mRNA表达(P<0.01)。与正常组比较,PTH呈浓度依赖性地增加了ERK1/2和p-ERK1/2的表达(P<0.01)。结论1×10-7,1×10-6mol/L rPTH1-34能在体外诱导新生大鼠心室肌细胞发生肥大反应,且呈一定的浓度依赖性;PTH能呈浓度依赖性地刺激心肌ERK1/2过度表达。

THE CHARACTERISTICS OF ENDOGENOUS OUABAIN SECRETION FROM CULTURED BOVINE ADRENOCORTICAL CELLS

Objective To compare the characteristics or endogenous ouabaln(EO) secretion with the other adrenocortical hormones and determine the effects of angiotensin I (Ang I ), and ad reno corticotrophin (ACTH ) on the secretion or EO. Methods EO was measured by radioimmunoassay from primary cultured bovine adrenocotical cells (BAC). Results oouabain was determined in the media or cultured BAC. Both EO and aldosterone secretion were decreased from the 6uter to inner layer or the cultured adrenal cortex, and the responses to Ang I and ACTH were hlgher than that in the mld layer (P <o. o5) and inner layer (P <o. o1 ). Cortisol secretion was activated by Ang I or ACTH was slgnificantly higher in the mid layer and in the inner layer than that in the outer layer. The tlme-course experlment showed that the gradually rising amounts or aldosterone and cortisol could be determined during the continuous incubation to 48h wlth or without Ang I or ACTH. However, EO did not increase continuously arter 24h or incubation in the basal secreting sltuation and arter 12h of lncubatiou in the stimulating situation by Ang,or ACTH. There were obvlous drops in aldosterone and cortisol secretlou from 3rd day during a 21 day-perlod cell culture, but the peak secretion of ouabain was in 7th day. Conclusion it suggests that the secretory mechanism might be different between EO and aldosterone or cortisol. Also, Ang I and ACTR might be involved in the regulation of Eo secretion.

甲状腺激素对大鼠脑干听觉诱发电位快慢成分发育的影响

目的：探讨甲状腺激素对大鼠脑干听觉诱发电位快成分（FC—BAEP）和慢成分（SC-BA—EP）的影响。方法：孕鼠孕第1天至仔鼠出生后30d饮含0．03％甲硫咪唑的自来水诱发甲状腺功能低下（甲低）仔鼠，每天腹腔注射左旋甲状腺素（L-T4，0．02mg／kg）进行替代治疗。分为H组（甲低组）、RP1组（出生后1～30d替代治疗组）、RP7组（出生后7～30d替代治疗组）、RP14组（出生后14～30d替代治疗组）、RP21组（出生后21～30d替代治疗组）和正常对照组。放射免疫法测定大鼠血清游离三碘甲腺原氨酸（FT3）和四碘甲腺原氨酸（FT4）。计算机平均叠加技术颅表记录大鼠FC-BAEP和Sc-BAEP。结果：RP1组大鼠FC—BAEP和SC—BAEP引出时间正常，RP7和RP14组大鼠则延迟引出，RP21和H组大鼠更晚引出；RP1、RP7、RP14和RP21组大鼠FC—BAEP和SC—BAEP延长的波峰潜伏期（PL）和波峰间潜伏期（IPL）在出生后60d内可明显改善至正常，但至正常时间依次延后，而H组大鼠的PL和IPL在出生后60d仍明显延长。结论：甲状腺激素对大鼠FC—BAEP和SC-BAEP的发育有显著影响。

Turner综合征的生长激素水平

目的：探讨Turner综合征的生长激素水平和人生长激素治疗效果．方法对不同核型的Turner综合征患者19例进行生长激素激发试验，并对部分对象7例用人生长激素治疗。结果生长激素完全缺乏者9例，部分缺乏者8例，正常2例。接受人生长激素治疗7例，治疗前年增长速率均≤2cm，治疗后较前有所增长，效果最好者7个月增长5．6cm。结论Turner综合征的矮小与生长激素水平有一定的关系，用人生长激素治疗能使之改善。