大鼠固定脑双侧脑桥尾侧网状核间联系的研究-Dil荧光标记法

本文用Di1荧光染料作轴突示踪剂,主要在大鼠死后固定脑组织上研究双侧脑桥尾侧网状核间联系。结果发现:大量标记纤维聚集成小束,自一侧脑桥尾侧网状核越过中线至对侧同名核,标记纤维呈桔红色、强荧光,直径约1-2微米,纤维主要集中该核的腹侧区。当这些纤维达对侧网状结构内的脑桥尾侧网状部位,其中有些纤维分为上升、下降技。下降纤维行于两侧网状结构的内侧部,同侧约可追踪4-7毫米,对侧约2毫米左右,纤维在下降过程中逐渐减少。活体注射后,可见少量越过中线纤维,并在两侧网状结构内侧部见到少量纤维和散在的终末样纤维。双侧锥体束内均见大量标记纤维,除少数例子外,对侧荧光强度强于同侧。少量交叉纤维入对侧锥体束后入脑桥尾侧网状核。本文还对新近使用于神经解剖研究的荧光染料Dil的优、缺点进行了探讨。     

热盐水致大鼠萎缩性胃炎胃粘膜组织细胞增殖与凋亡的实验研究

目的　研究热盐水灌胃导致的大鼠萎缩性胃炎胃粘膜组织中的凋亡细胞及增殖细胞表达状态 ,以探讨长期热咸饮食与慢性萎缩性胃炎发生的关系。方法　采用脱氧核糖核酸转移酶介导的缺口末端标记 (TUNEL)技术及免疫组织化学染色技术。细胞凋亡时DNA含量分析采用流式细胞检测技术。结果　①TUNEL检测细胞凋亡显示 :在热盐水所致的大鼠萎缩性胃炎中凋亡细胞数明显增多 ,在粘膜全层均可见到 ,呈弥漫性分布。萎缩性胃炎中凋亡细胞指数显著高于正常大鼠胃粘膜 (P <0 .0 5) ;②免疫组化法检测显示 :增殖细胞核抗原 (PCNA)在热盐水灌胃所致的萎缩性胃炎中的表达率显著高于正常胃粘膜 (P <0 .0 5) ;③流式细胞检测显示 :萎缩性胃炎时 ,在G0 /G1峰前可见一个亚G0 /G1峰 ,也即凋亡细胞峰出现 ,而在正常胃粘膜时未显示亚G0 /G1峰。结论　热盐水灌胃可导致大鼠胃粘膜组织细胞增殖和细胞凋亡异常 ,其在热盐水所致的大鼠萎缩性胃炎发生中起重要作用。     

Diuretic and hypotensive actions of torasemide in hypertensive models of rat

The diuretic and the antihypertensive actions of torasemide were examined in renal and genetic hypertensive rats and compared to the effects of furosemide. Oral administration of torasemide (1 and 3 mg/kg) elicited a dose-dependent increase in the excretion of urine and electrolytes and elevated the urinary Na/K ratio in both renal and genetic hypertensive rats. Torasemide and furosemide had a similar maximum diuretic effect in the normotensive Wistar rat and the spontaneously hypertensive rat (SHR). However, the diuretic activity of furosemide was weaker in the renal hypertensive rat (RHR). Torasemide showed approximately 30 times greater diuretic potency than furosemide. Torasemide and furosemide demonstrated hypotensive action in hypertensive rat models, but not in the normotensive Wistar rat. Especially in the RHR, torasemide exhibited a more potent hypotensive action than furosemide. These results show that the diuretic and antihypertensive activities of torasemide are effective in various rat models of hypertension, while the diuretic activity of furosemide is weak in certain hypertensive rat models. © 1992 Wiley-Liss, Inc.     

Modulators of growth in primary culture of rat proximal tubular cells II

Summary: The present studies assessed the effects of manipulating extracellular sodium (Na) concentration and Na transport on cellular hypertrophy and hyperplasia in primary culture of rat proximal tubular cells. A concentration-dependent effect on thymidine incorporation and protein content was observed with cell culture media Na concentration of 130, 140 and 150 mmol/L. This effect was independent of osmolality (matched with mannitol) and no stimulatory effect occurred if choline was substituted for Na. Cells derived from sham-operated (Sx) animals exposed to a higher media concentration of Na (150 vs 140 mmol/L) had both stimulated thymidine incorporation to 186.8 ± 35.41% (P<0.05) and enhanced cell protein content to 134.7 ± 135% (P<0.05). This effect was more pronounced in cell cultures derived from unilaterally nephrectomized (Nx) animals, being 212.8 ± 31.5% (P<0.01) for thymidine incorporation (P<0.05 vs cells from sham-operated animals grown in high Na media) and 114.4 ± 3.2% (P<0.001) for protein content (P=0.11 vs sham-operated cells grown in similar conditions). the addition of 10^?4 mmol/L ethylisopropyl amiloride hydrochloride (EIPA) to Nx cells in a normal or high Na concentration media resulted in a decrease in cellular protein content to 82.6 ± 6.8% (P<0.05) and 85.5 ± 0.2% (P<0.0001) compared to respective controls. 10^?4 mol/L EIPA in media supplemented with insulin-like growth factor (IGF-1) blocked the proliferative response normally seen in response to this growth factor from 156.6 ± 13.7 to 27.5 ± 3.1% (P<0.0001) compared to control. However, the presence of EIPA did not abrogate the hypertrophic response elicited by IGF-1 (cell protein content 128.1 ± 13.1% of control with IGF-1 vs 124.9 ± 12.5 with IGF-1 and EIPA; P= n.s.). Addition of 10^?4 mol/L EIPA to 10% serum derived from either Sx or Nx animals blocked the growth response to the sera, limiting the cellular protein content to 76.6 ± 5.5% (P<0.0001) and 89.7 ± 4.4% (P<0.0001) and thymidine incorporation to quiescent levels of 0.2 ± 0.1% (P<0.0001) and 0.4 ± 0.1% (P<0.0001) compared to respective controls. In summary, rat renal proximal tubular cell growth is influenced by Na concentrations in the cell culture environment and inhibited in the presence of EIPA. This supports a role for altered epithelial transport in the cellular growth response to a number of stimuli.     

Light-emitting diodes and half-cell electrodes in experimental recording of electroretinogram c-wave

A method of electroretinogram c-wave recording in the rat was developed that uses a contact lens electrode connected through a saline bridge with a silver-silver chloride half-cell. A cluster of light-emitting diodes, regulated by an electronic light-emitting diode stimulator, was used as a light source. The method enables recordings of c-waves of 0.4–1.6 mV amplitude as well as other electroretinogram components in narrow limits of variation. The two main sources of response variability are voltage shunting and eyeball protrusion.     

Effect of water restrictions on the physiological parameters,psychological behavior and brain c-Fos expression in rat

1 Introduction Exposure to hostile stressors causes a series of coor- dinated responses in the body, such as alterations of neu- roendocrine secretion, immune reaction and behavioral manifestation to maintain homeostasis stability and sur-vival of the organisms. Stressors are divided into two main categories: physical, or systemic, and psychological, or emotional / processive. Each stressor might activate a spe- cific central pathway to induce a special neuroendocrine response, even cause stre…     

Histological changes in the midbrain around the aqueduct in congenital hydrocephalic rat LEW/Jms

Primary aqueductal stenosis is one of the main causes of congenital hydrocephalus in humans and experimental models. The congenitally hydrocephalic rat strain LEW/Jms is one such model. In this report, we describe further detailed histological features of periaqueductal structure, including the posterior commissure, subcommissural organ (SCO), and ependyma, and discuss the changes in these structures in relation to the cause of hydrocephalus. Coronal sections of the aqueduct in normal rats showed that the usual ependyma was absent in the center of the base facing the dorsal side, which was replaced by tall columnar cells. On the other hand, in hydrocephalic rats the ependyma encircled the aqueductal cavity. In midline sagittal sections, normal and hydrocephalic rats showed the SCO, although the SCO in hydrocephalic rats was shorter than in normal rats. There was also a marked difference between normal and hydrocephalic rats in the dorsoventral dimension of the rostral midbrain. In hydrocephalus, this dimension was large in comparison with normal rats. The superior collicular commissure located caudal to the posterior commissure ran along the ventral side of the midbrain in rats with hydrocephalus, and there was a cell-depleted area just dorsal to the superior collicular commissure. The same findings were observed from the 17th day of gestation until the postnatal period. Although the role of the SCO has been widely discussed from the viewpoint of secretory function, the present study indicated that this organ might be involved in the formation of the shape of the aqueduct.     

不同时辰刺激大鼠的交叉上核对血浆中皮质酮含量的影响

应用拉丁方设计，在不同体重组的大鼠，于不同时辰，对交叉上核采取不同强度的刺激，用放射免疫法测定外周血中皮质酮的含量。其结果显示：各体重组间无显著性差异，不同时辰血浆皮质酮的平均含量各组呈现基本相同的节律性变化，无论何时辰刺激交叉上核使之兴奋，均可显著提高血浆皮质酮的含量。完全损毁交叉上核后７２小时血浆皮质酮含量和正常对照组无显著性差异，且其节律性也没有出现明显变化。     

ApoMT对CdMT肾毒性保护作用研究

本文研究了去除金属离子的金属硫蛋白（ApoMT）对镉金属硫蛋白（CdMT）肾毒性作用的影响。结果发现，与单独给予CdMT比较，ApoMT能降低尿蛋白量和尿碱性磷酸酶（AKP）活性，并能促进尿Cd的排泄。肾组织形态学结果显示肾近曲小管损伤程度明显减轻。提示ApoMT对CdMT肾小管损伤具有保护作用。