大鼠马桑内酯急性局灶型癫痫大脑运动皮质的形态计量研究

用微量马桑内酯注入Ｗｉｓｔａｒ大鼠左侧前肢运动皮质，造成急性局灶型癫痫。用光镜、电镜和体视学方法研究其运动皮质第Ｖ层结构的改变。结果显示：癫痫大鼠运动皮质灶区、灶旁区的神经细胞数和胶质细胞数均分别比对照大鼠灶区和灶旁区显著减少；灶区神经毡中突触性终末数，显著减少；突触性终末的面积分数明显减少，而树突的面积分数无变化；神经胶质突起的面积分数增加。     

Numerical data on neocortical neurons in adult rat, with special reference to the GABA population

The disector method was used to estimate the numerical density of neurons (number per unit volume) and their actual number per column (number under a given area of pial surface), in the occipital (monocular segment of the primary visual area, Oc1M), the parietal (somatosensory barrelfield area, Par1) and the frontal cortex (primary motor area, Fr1) of adult rat. Values were first obtained for all neurons in each layer, and then for GABA neurons as identified with postembedding immunocytochemistry on semithin sections. The numerical density of neurons in the frontal cortex (34,000/mm³) was significantly lower than in the two other neocortical areas (occipital: 52,000; parietal: 48,000/mm³). The GABA population showed a similar difference and consequently represented an equivalent proportion of total (15%) in the three cortical areas. Across layers, there was an alternate distribution of low and high density of neurons from layers II–III to VI in the three cortical areas, with the highest density in layer IV of the two sensory areas. The laminar changes in density of the GABA neurons were not as pronounced as those of the overall population. Consequently, the layers with the highest overall neuronal densities tended to have a lower proportion of GABA neurons and vice versa. There were more neurons under 1 mm² of surface in the parietal (90,000) than the occipital or the frontal cortex (71,000), which was also true of the GABA neurons. The greater number of neurons per column in the parietal cortex was mostly imputable to layer IV, the main recipient of thalamic axons. Comparing these values from the rat with those previously obtained in cat and monkey, it seemed that the number of neurons per cortical column was the highest in the sensory area preferentially used by each species.     

Protective actions of human recombinant basic fibroblast growth factor on MPTP-lesioned nigrostriatal dopamine neurons after intraventricular infusion

Basic fibroblast growth factor (bFGF, FGF-2) is a trophic factor for neurons and astrocytes and has recently been demonstrated in the vast majority of dopamine (DA) neurons of the ventral midbrain of the rat. Potential neuroprotective actions of FGF-2 in the l-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP) model have also been reported. The actions of the FGF-2 have now been further analyzed in a combined morphological and behavioural analysis in the MPTP model of the adult black mouse, using a continuous human recombinant FGF-2 (hrFGF-2) intraventricular (i.v.t.) administration in a heparin-containing (10 IU heparin/ml) mock cerebrospinal fluid (CSF) solution. Tyrosine hydroxylase (TH) immunocytochemistry in combination with computer assisted microdensitometry demonstrated a counteraction of the MPTP-induced disappearance of neostriatal TH-immunoreactive (ir) nerve terminals following the FGF-2 treatment. Unbiased estimates of the total number of nigral TH ir neurons, using stereological methods involving the optical disector (Olympus), showed that the MPTP-induced reduction in the number of nigral TH ir nerve cell bodies counterstained with cresyl violet (CV; by 56%) was partially counteracted by the FGF-2 treatment (by 26%). The behavioral analysis demonstrated an almost full recovery of the MPTP-induced reduction of the locomotor activity after FGF-2 treatment. This action was maintained also 1 week after cessation of treatment. The hrFGF-2 produced an astroglial reaction as determined in the lateral neostriatum and in the substantia nigra (SN) far from the site of the infusion, indicating that the growth factor may have reached these regions by diffusion to activate the astroglia. Immunocytochemistry revealed FGF-2 immunoreactivity (IR) in the nuclei of the astroglia cell population in the dorsomedial striatum and the microdensitometric and morphometric evaluation demonstrated an increase in the number, but not in the intensity, of these profiles on the cannulated side, suggesting the possibility that hrFGF-2 stimulates FGF-2 synthesis in astroglial cells with low endogenous FGF-2 IR. These results indicate that hrFGF-2, directly and/or indirectly via astroglia, upon i.v.t. infusion exerts trophic effects on the nigrostriatal DA system and may increase survival of nigrostriatal DA nerve cells exposed to the MPTP neurotoxin.     

Stereological analysis of Reinke's crystals in human Leydig cells

Summary Reinke's crystals in human Leydig cells were analyzed stereologically to assess their functional role. Testicular tissues were taken from seven older men (57–82 years old) with prostatic carcinoma and also from seven younger men (26–38 y.o.) complaining of male infertility. Sections 0.5 m thick, stained with toluidine blue or Heidenhein's iron-hematoxylin were examined by a point-counting method and with a Particle Measurement Computor System (MC). When the patients were grouped by age, the mean crystal volume, the number of crystals per cell, the volume of crystals per cell and the volume ratio of crystals to cell were significantly larger in the older age group than in the younger age group. In particular, the latter three variables correlated well with the age of subjects, with correlation coefficients of r=0.66–0.85. On the other hand, none of these variables had any correlation with the concentration of plasma testosterone. These results indicate that Reinke's crystals can be considered as degenerative products in cell life but not as facultative constituents for testosterone production.Supported in part by a grant from Medical Foundation of Ehime, Japan     

Fate of the type II pneumocyte following tracheal occlusion in utero: a time-course study in fetal sheep

 Tracheal occlusion in utero has been shown to cause accelerated fetal lung growth and is now being considered as a therapeutic modality for pulmonary hypoplasia. We report the effects of tracheal ligation on the surfactant-producing type II pneumocyte population. Three groups of fetal lambs underwent tracheal ligation of 2 weeks’, 4 weeks’ and 6 weeks’ duration, respectively, and all were sacrificed at 136 days’ gestation (9 days pre-term). Nonoperated twins served as controls. The type II pneumocyte population was studied morphometrically using a combination of anti-surfactant protein B immunohistochemistry and computer-assisted stereologic morphometry at light and electron microscopic levels. Single-factor ANOVA was used for statistical analysis. Two weeks of tracheal ligation resulted in doubling of the total lung volume as a result of airspace distension and, to lesser extent, growth of the tissue compartment. With increasing duration of tracheal ligation, there was no additional lung growth. However, more prolonged tracheal occlusion was found to result in significant reduction of the surfactant system, as reflected in the marked decrease of total pneumocyte type II volume (3.14 cm³, 0.95 cm³, and 0.46 cm³, after 2, 4, and 6 weeks of ligation, compared with 5.96 cm³ for controls) and total pneumocyte type II number (13.9 × 10⁹, 3.8 × 10⁹, and 2.4 × 10⁹, compared with 53.2 × 10⁹ for controls). Ultrastructural analysis of the type II cells in obstructed lungs showed vacuolar degenerative changes that, after 6 weeks of ligation, were apparently irreversible. In utero tracheal ligation causes fetal lung hyperplasia, but results in reduction of and injury to the surfactant-producing cell population. Before tracheal occlusion can find widespread clinical application, its pathophysiology needs to be further elucidated. Received: 30 April 1997 / Accepted: 10 July 1997     

Effects of combined renovascular hypertension and diabetes mellitus on myocardial cells,non-vascular interstitium and capillaries: a stereological study on rat hearts

Summary The effects of combined renovascular hypertension and diabetes mellitus on the rat heart were investigated in order to detect possible synergistic effects of the two conditions. Hypertensive diabetic and hypertensive non-diabetic animals were compared to diabetic and non-diabetic controls. Hypertension was established for 12 weeks by a surgical stenosis of the left renal artery; diabetes mellitus was maintained for 8 weeks by a single intraperitoneal injection of 60 mg/kg streptozotocin. Light microscopic stereology did not reveal significant divergences between diabetic hypertensives and non-diabetic hypertensives. Hypertension induced a focal perivascular and interstitial fibrosis with increased volume densities of non-vascular interstitium and fibrosis (P<0.001). Capillary density (Q_A) was decreased in transverse sections (P<0.01) and increased in longitudinal sections (P<0.01). This indicates a three-dimensional remodelling of the capillary bed with an increased number of obliquely running capillaries. At least the length density (L_V) of capillaries (mm/mm³) tends to be normalized in long-term renovascular hypertension. At the ultrastructural level, a synergism of hypertension and diabetes mellitus was observed: the volume ratio of mitochondria to myofibrils was significantly decreased in hypertensive diabetics, but not in non-diabetic hypertensives or in diabetics. This may enhance the risk of cardiac deterioration. We conclude that the primary target of the synergistic damage in hypertensive diabetic heart muscle disease is the myocardial cell and not the cardiac interstitium.Preliminary results of this study have been published in: Mall G (1991) Morphometric study on the rat heart in combined renovascular hypertension and diabetes mellitus. In: Nagano N, Dhalla NS (eds) The diabetic heart. Raven Press, New York, pp 115–124Dedicated to Prof. Dr. med. G. Seifert on the occasion of his 70th birthday     

Effects of high doses of testosterone propionate and testosterone enanthate on rat seminiferous tubules — a stereological and cytological study

The effects of exogenous testosterone on various testicular variables has become of increasing significance because of its potential use in male contraception. For this reason, high doses of two testosterone esters [testosterone propionate (TP) and testosterone enanthate (TE)] were used in a study of their influence on the morphology, length and curvature of the seminiferous tubules of the rat testis, and on cytological smears of the seminiferous tubules epithelium. TP was given for 14 days (3 mg/100 g body weight, i. m.) to assess the acute effects of testosterone on the seminiferous tubules. TE was administered for 60 days (in the same manner as TP) to study possible chronic effects on the rat testis. After TP and TE treatment the seminiferous tubule epithelium showed disorganization and desquamation of spermatogenic cells. In the TP-treated testes the tubules lined with Sertoli cells only were observed. The values for the length and curvature of seminiferous tubules of the TP- and TE-treated rats were significantly reduced (p<0.001). All these changes were observed earlier in the TP-treated than in the TE-treated animals. In cytological smears of the testis of the TP- and TE-treated rats an increase of vacuoles and residual bodies in Sertoli cell cytoplasm was noted. In addition, a reduction of spermatogenic cells, particularly sperms, was manifest in the smears after treatment. Large groups of Sertoli cells were seen in the smears from these testes.The study was supported by a Grant for Scientific Research No. 3-01-041 from the Ministry of Science, Technology and Informatics of the Republic of Croatia     

Effect of chronic lithium treatment with or without haloperidol on number and sizes of neurons in rat neocortex

The present study used stereological methods to determine whether long-term administration of lithium, with or without haloperidol, affects the number and average volume of neocortical neurons. Twenty-five rats were divided into three groups and given no treatment, lithium, or lithium combined with haloperidol. Serum lithium levels ranged from 0.5 to 0.8 mmol/l. Haloperidol was injected intraperitoneally at a daily dose of 1 mg/kg. After 30 weeks of treatment, the animals were killed and the brains were prepared. Neocortical volume, density of neurons, total number of neurons and mean volume of neurons were estimated. As no differences were found between the groups, the present study provides no evidence for quantitative morphological changes in the cerebral cortex due to long-term therapeutic levels of lithium, with or without haloperidol.     

Estimation of the amniotic fluid volume using the Cavalieri method on ultrasound images.

OBJECTIVES: Presently, a design-based and practical method for measuring amniotic fluid volume (AFV) for routine clinical examinations has not been proposed. In this study we describe a new method, which combines the Cavalieri method with ultrasound imaging to estimate AFV. METHODS: We measured the AFVs of 14 women in the third trimester of pregnancy, and repeated our measurements three times for each woman. Parallel planimetric ultrasonographic images were obtained at every 2 cm along the longitudinal uterine axis. AFVs were calculated as the total of the multiples of the estimated cut surface areas by the section thickness. RESULTS: The mean estimated AFV was 380.5 cm3. The coefficient of error of each measurement was calculated and the mean was 0.108. The coefficient of correlation between the amniotic fluid index and our AFV estimations was 0.87. CONCLUSIONS: Design-based and efficient estimation of AFV is possible with the combination of consecutive ultrasound images and the Cavalieri method.     

运动与负荷对大鼠骨形态影响的无偏体视学观察

为探讨运动对青少年长骨发育的机理,本研究以大鼠作为实验模型,使生长期大鼠进行不同强度的跑台运动,同时结合悬吊和负重模型,采用体视学全视野无偏采样方法对不同强度运动和不同形式机械负荷的生长期大鼠骨量、骨结构、骨代谢等形态参数进行测试分析,取得运动与负荷对大鼠长骨发育影响的系列结果,为儿童少年生长发育状况的评价、运动和其它干预手段的选择以及运动处方的制订等提供部分依据。