Immunocytochemical demonstratin of c-fos protein in sertoli cells and germ cells in rat testis

The juxtaglomerular apparatus fulfils several important regulatory functions in the kidney, such as tubuloglomerular feedback (TGF) control and control of renin release. The macula densa (MD) cells sense the fluid load by perceiving the distal NaCl concentration via a Na-K-2Cl cotransport system in the luminal cell membrane. It has been proposed that macula densa cell activation may involve changes in intracellular cytosolic free calcium concentration ([Ca²⁺]₁), as one link in the chain of events activating TGF or releasing renin. We therefore investigated the changes in the intracellular calcium concentrations with fura-2, using a video system, in macula densa cells, and compared them with the changes in the corresponding concentrations in the ascending limb of the loop of Henle (c-TAL). The results show that our technique for analysing intracellular cystolic free calcium in isolated perfused tubules is valid for this purpose, and the K_d value obtained was similar to that found by Grynkiewicz et al. (1985). The intracellular cystolic free calcium concentration was about 90 nM both in the macula densa and c-TAL cells, and the macula densa cell intracellular cystolic free calcium concentration increased by about 20 nM when the tubular lumen was perfused with Na and C1 at low concentrations. No significant changes were noted when furosemide was added to the perfusion solutions. We consider it hardly likely that this small change in intracellular cystolic free calcium concentration can be entirely responsible for full activation of renin release or full inactivation of the TGF control mechanism. It would seem that the signal transmission from the macula densa cells could occur by other routes than through activation of intracellular cytosolic free calcium concentration.     

卵巢上皮性囊腺性肿瘤组织中C-erbB-2、PCNA和p53蛋白的表达及临床病理学意义

目的 :探讨原癌基因C erbB 2、增殖细胞核抗原 (proliferatingcellnuclearantigen ,PCNA)、抑癌基因p5 3在卵巢上皮性囊腺性肿瘤组织中的表达及其临床病理学意义。方法 :应用抗生蛋白链菌素标记法 (LSAB)和图象分析系统方法检测卵巢上皮性囊腺性肿瘤组织中 (其中 61例良性肿瘤、19例交界性肿瘤、4 4例恶性肿瘤 )C erbB 2、PCNA及p5 3蛋白的表达。结果 :1)C erbB 2、PCNA、p5 3三指标在囊腺瘤、交界性囊腺瘤、囊腺癌中阳性表达率均呈梯度升高 ,差异有极显著性 (P <0 0 0 1)。其中PCNA与p5 3在浆液性囊腺癌组织中的表达显著高于交界性肿瘤及黏液囊腺癌组织 (P <0 0 5 )。 2 )C erbB 2、PCNA和p5 3在囊腺瘤组织中的阳性细胞平均积分光密度值 (染色强度 )均显著低于交界性瘤和恶性肿瘤 ,且差异有极显著性 (P <0 0 0 1)。 3)p5 3蛋白表达与囊腺癌临床分期、组织学分级有相关性 (P <0 0 5 )。 4 )p5 3+PNCA和C erbB 2 +PCNA +p5 3联合表达率在交界性囊腺瘤与囊腺癌之间差异有显著性 (P <0 0 1)。结论 :C erbB 2、PCNA和p5 3蛋白的高表达与囊腺癌的发生有密切关系 ,可作为卵巢上皮性囊腺性肿瘤恶性化的分子标志。PCNA和p5 3蛋白的免疫组化检测可成为卵巢上皮性囊腺性肿瘤鉴别诊断的客观辅助指标 ,并为其诊     

Bcl-2 mRNA和Bax mRNA在增生性瘢痕中的表达及意义

【目的】观察Bcl-2 mRNA和Bax mRNA在增生性疲痕和正常皮肤组织内的表达特征及其对增生性瘢痕形成的影响。【方法】收集20例增生性疲痕和20例正常皮肤组织，常规制作石蜡包埋切片，Bcl-2 mRNA和Bax mRNA染色方法为分子原位杂交染色法。【结果】Bcl-2 mRNA和Bax mRNA杂交信号阳性产物定位于胞浆。增生性疲痕Bcl-2 mRNA表达阳性率及其评分明显高于正常皮肤（P〈0．01）；增生性瘢痕Bax mRNA表达阳性率及其评分与正常皮肤无明显差异（P〉0．05）。【结论】Bcl-2基因表达增强可能是瘢痕中细胞凋亡减少，形成增生性瘢痕的机制之一。     

辛伐他汀含药血清对兔血管平滑肌细胞增殖及原癌基因表达的作用及意义

目的　探讨辛伐他汀对体外培养兔血管平滑肌细胞 (VSMC)增殖的影响及机制。方法　 16只雄性新西兰兔随机分为空白血清对照组和 3个不同剂量的辛伐他汀组 (5mg/kg、10mg/kg、15mg/kg) ,7d后采血并混合每组 4只兔血 ,无菌分离制备分组辛伐他汀含药血清。另采用内皮素 1刺激原代培养正常喂饲兔主动脉VSMC建立增殖模型 ,采用MTT及3 H TdR法检测分组辛伐他汀含药血清对VSMC增殖的作用 ,采用免疫细胞化学方法检测VSMCc myc、c fos抗原表达、RT PCR半定量检测c myc及c fosmRNA表达。结果　与对照组相比 ,不同分组辛伐他汀含药血清呈剂量依赖性抑制血管平滑肌细胞增殖 (P <0 0 5～ 0 0 1) ;免疫细胞化学及RT PCR结果表明 ,不同分组辛伐他汀含药血清呈剂量依赖方式抑制VSMCc fos和c mycmRNA表达(P <0 .0 5～ 0 .0 1)。结论　兔口服辛伐他汀后的血清抑制VSMC增殖 ,而辛伐他汀含药血清抑制c fos和c myc表达可能是其抑制VSMC增殖和抗动脉粥样硬化的机制之一。     

高血压性左心室肥厚与心肌原癌基因c-fos表达

采用自发性高血压大鼠(SHR)和两肾一夹型(2K1C)肾血管性高血压大鼠模型，研究细胞核内原癌基因c-fos在高血压性左心室肥厚(LVH)发生，发展过程中的作用. 结果表明：SHR在8-10周龄时已有明显的高血压和LVH，其收缩压(SBP)与左室重/体重比(LVW/BW)均显著高于同龄的WKY大鼠. 20-22周龄与40-42周龄时，SHR的SBP，LVW/BW及左心室c-fos基因表达水平均明显高于同龄对照组WKY大鼠. 2K1C大鼠左肾动脉缩窄1周后发生明显的LVH，同时伴左心室c fos基因的高表达，至术后3和10周仍保持较高水平. 钙拮抗剂尼群地平(10 mg·kg^-1 ig，每日2次，连续10周)或血管紧张素AT₁受体阻断剂洛沙坦(30 mg·kg^-1·d^-1 ig，连续10周)治疗均可逆转2K1C大鼠SBP的增高和LVH的发生与发展，同时左心室c-fos基因表达水平降低. 结果提示心肌原癌基因c-fos的高表达参与高血压性LVH的发生，发展过程.     

卡托普利早期治疗自发性高血压大鼠抑制左室肥厚和c-myc表达而不影响c-fos表达(英文)

目的:探讨早期卡托普利治疗抑制左室肥厚的机制.方法:♂SHR宫内期给药(100 mg·kg~(-1)·d~(-1))到16周,40周处死,测定收缩压,左室重与体重比,左室c-myc和c-fos表达量(Northern杂交).结果:治疗明显降低血压,停药后24周,仍维持较低血压(20.9±1.2vs对照SHR 28.3±1.3 kPa,P<0.01)并抑制左室肥厚,心肌c-myc表达明显减少(0.57±0.13 vs对照SHR 2.07±0.16,c-myc mRNA/18S rRNA,P<0.01),c-fos表达无变化.结论:卡托普利持久地阻止高血压形成,抑制左室肥厚.后者可能是抑制c-myc表达结果,治疗不改变c-fos表达.     

The Effects of Colectomy on Immediate–Early Proto-Oncogene Expression and Hepatic Regeneration in the Rat

The intact liver exists in a state of replicative quiescence. The factor(s) responsible for maintaining this state and their tissue sources have yet to be identified. Because the colon synthesizes and/or absorbs numerous agents that inhibit hepatocyte proliferation, the principle purpose of this study was to determine whether total colectomy would result in the conversion of quiescent livers to a state of replicative competence. Thus, adult, male Sprague-Dawley rats (250–300 g) were randomized to undergo either total colectomy with ileostomy or sham surgery. Thereafter, rats were sacrificed (N = 3–6/group) at times 15 and 30 min and 1, 2, 6, and 24 hr and the livers analyzed by Northern blot analyses for mRNA of the following immediate–early proto-oncogenes (IEP genes): c-fos, c-jun, and c-myc. Rats sacrificed at 24 hr also had hepatic regenerative activity documented by [³H]thymidine incorporation into hepatic DNA. The results of the study revealed that within 15 min, c-fos and c-jun mRNA expression increased in colectomized rats, with peak expression occurring at 30 and 60 min, respectively. c-myc mRNA expression was more delayed, with peak expression occurring at 6 hr postcolectomy. IEP gene expression also increased somewhat in sham-colectomy controls but the increases were not as prompt and, in general, were of lower magnitude than those in the colectomy group. Despite the differences in IEP gene expression between the two groups, [³H]thymidine incorporation at 24 hr was similar (mean ± SE: colectomy group, 17.2 ± 2.6 dpm/μ g DNA; sham-colectomy controls, 14.8 ± 1.4 dpm/μg DNA). To determine whether the increases in IEP gene expression expedite or augment the hepatic regenerative response to partial hepatectomy (PHx), rats that had undergone colectomy or sham colectomy 1 hr earlier and rats with no previous abdominal surgery then underwent a 70% PHx and were sacrificed at 8, 16, and 24 hr thereafter. At each time interval, [³H]thymidine incorporation was documented and found to be similar in the three groups. In conclusion, the results of this study indicate that total colectomy, and to a lesser extent abdominal surgery, induces the conversion of an intact, quiescent liver to a state of replicative competence. The results also suggest that, in addition to colectomy, the presence of mitogens and/or co-mitogens is required for further progression of hepatocytes through the cell cycle. Finally, a “primed” liver does not respond more promptly or vigorously to a regenerative stimulus than a “resting” liver.