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[目的]研究环境水平三苯基锡(triphenyltin,TPT)对哺乳动物肾上腺的毒性作用。[方法]将40只青春期SD大鼠随机分为3个不同剂量的试验组[0.5、5、50μg/(kg·BW)]和1个对照组[0μg/(kg·BW)]。每3 d灌胃1次,暴露54 d后,用10%水合氯醛麻醉并处死大鼠,采用石蜡切片和HE染色的方法观察SD大鼠肾上腺组织学变化特点。[结果]对照组SD大鼠肾上腺组织结构正常,皮质部球状带、束状带、网状带内细胞结构正常,胞核明显;髓质部细胞呈多边形或圆形,排列不规则,索间有血窦。与对照组相比,低剂量组肾上腺皮质和髓质内细胞的结构均无明显变化。中剂量组肾上腺球状带稍变薄,束状带和髓质细胞的胞核固缩、胞质溶解,间质组织轻微出血。高剂量组球状带细胞显著减少,与束状带界限不清,束状带细胞和髓质部细胞胞核固缩,胞质溶解现象加重,呈现细胞空泡化现象,间质组织增厚且出血现象明显。[结论]证实了一定剂量的TPT对SD大鼠肾上腺组织结构具有一定损伤作用,且呈剂量依赖性,该结果为研究TPT对哺乳动物内分泌的影响提供了形态学资料。  相似文献   

3.
The thymus gland of the guinea fowl appeared as a series of pink, irregular-shaped lobes along the jugular veins. These lobes were 13 in number with seven on the right and six on the left side. The third and sixth lobes on the right side were the largest. The largest lobe measured about 20.0 × 5.0 mm while the smallest measured about 5.0 × 4,0 mm. Histologically, it was encircled by a thin layer of poorly stained connective tissue from which strands penetrated the thymic tissue giving incomplete lobules peripherally as early as day 18 of incubation. Lymphocytes and reticular epithelial cells were the two types of cells occurring at this time. Reticular epithelial cells were observed to be vacuolated especially towards the centre of the gland. Macrophages were observed in the thymus on day 20 of incubation for the first time. The blood vessels had accompanied the interlobular septa into the thymus. By day 21 of incubation, blood vessels had actually penetrated the thymic tissue but most of these vessels were of the capillary size. The cortex also became quite distinct from the medulla. At day 22, vacuolation ceased to appear in the cells at the cortical zone. Macrophages were still less than 10 in the slide. At day 23, most blood vessels were within the medulla and they displayed compressed lumi-na. Mitotic figures became a common site amongst the large lymphocytes and reticular epithelial cells. By day one post-hatch, lobulation of the thymus was still poor and macrophages became difficult to identify. The small and medium lymphocytes had outnumbered the large lymphocytes throughout the thymic tissue except at the most peripheral zone of the cortex. Fine vacuoles had reappeared within the cytoplasm of the reticular epithelial cells in the cortex. By day five, the distribution of blood vessels was almost uniform between the cortex and medulla. At three weeks post-hatch, plasma cells and red blood cells were seen in the stroma of the gland for the first time and most of the red blood cells occurred in the medulla.  相似文献   

4.
With 14 figures and 3 tables SUMMARY: Each adrenal gland consisted of cortex and medulla that developed from different embryological origins and presented different cellular organization. One hundred male or female camel embryos or fetuses with crown vertebral rump lengths (CVRL) that ranged from 0.8 to 117 cm were examined. The adrenal cortex, which is derived from intermediate mesoderm, was first observed in the 0.8-cm CVRL camel embryo. The adrenal cortex initially was combined with the gonad as a thickened region of proliferating cells derived from splanchnic intermediate mesoderm. Adrenocortical tissue was first separated from the gonadal tissue in the 2-cm CVRL camel fetus and was observed as a separate dorso-medial mass of cells. At 2.5-cm CVRL, the adrenocortical tissue was surrounded by a capsule of undifferentiated mesenchymal cells, except at its proximal pole, where an invagination was located through which chromaffinoblast cells entered the cortex. The chromaffinoblast cells migrated from the neural crest to form the medulla of the developing adrenal gland. In the 3.5-cm CVRL camel fetus, the adrenocortical cells differentiated into two layers: the inner fetal cortex and the outer definitive cortex. As development proceeded, the fetal cortex degenerated and the definitive cortex formed the zona glomerulosa and zona fasciculata. The zona reticularis did not form until the end of gestation. During prenatal life, the adrenal medulla was much thicker than the cortex.  相似文献   

5.
The morphological relationships of the pineal complex to the epithalamic structures have been examined at light microscopic level in five desert rodent species, Meriones crassus , Meriones lybicus , Gerbillus gerbillus , Psammomys obesus and Ctenodactylus vali . The pineal complex is classified as type ABC in M. crassus and G. gerbillus, AC in M. lybicus, AβC in P. obesus and αβC in C. vali. In these rodent species, the pineal is an elongated organ which is dumbbell-shaped in G. gerbillus and M. lybicus, and extends above the cerebral hemispheres in M. crassus , leaf-shaped in P. obesus and lancet-shaped in C. vali. In P. obesus, pigment-containing cells are noted in the superficial part of the gland. In all species examined, the suprahabenular recess which is an extension of the choroid plexus of the third ventricule establishes a close anatomical relationship with the deep pineal. In C. vali, the suprahabenular recess is also contiguous with the pineal stalk and the superficial pineal component. In M. lybicus, M. crassus, G. gerbillus and P. obesus , a prominent dorsal vessel, the vena cerebri magna , intervenes between the suprahabenular recess, the superficial portion and the stalk. The most striking feature noted in this study is the presence of numerous melanocytes in the connective tissue capsule of the pineal gland, in the connecting stalk and in the connective tissue core of the highly convoluted suprahabenular recess in M. lybicus and M. crassus . The location of melanocytes in the restricted pineal area may suggest that these cells have a morphosignificance in photoreception or photoprotection.  相似文献   

6.
The structure of the adrenal gland was studied in 11 bottlenose dolphins ( Tursiops truncatus ), and five striped dolphins ( Stenella coeruleoalba ). These species are legally protected in Croatia. All examined animals died of natural causes and were found stranded along eastern Adriatic coast. In both species the adrenal gland consists of a cortex and a medulla; the cortex is divided into three zones. Whereas in the bottlenose dolphin, there is a zona arcuata which contains columnar cells arranged in the form of arches; in the striped dolphin this zone is replaced by zona glomerulosa containing rounded clusters of polygonal cells. In both species, the zona fasciculata consists of radially oriented cords of polygonal cells, whereas in zona reticularis cells are arranged in branching and anastomosing cords. The adrenal medulla in both species contains dark, epinephrine-secreting cells and light norepinephrine-secreting cells. Epinephrine-secreting cells are localized in the outer part of the medulla, whereas norepinephrine-secreting cells are found in the inner part, arranged in clusters and surrounded by septa of thin connective tissue. The gland is surrounded by a thick connective-tissue capsule, from where thick trabeculae extend towards the interior. In the bottlenose dolphin, group of cells resembling both medullar and cortical cells can be seen within the capsule; whereas only groups of cells resembling cortical cells are found within the capsule of the striped dolphin. In the bottlenose dolphin invagination of the adrenal cortex into the medulla is obvious as well as medullary protrusions extending through cortex to the connective tissue capsule.  相似文献   

7.
The purpose was to observe the changes in a rat pineal gland using stereological techniques during lactation and post-weaning periods. Thirty Wistar albino rats were studied during different post-natal periods using light microscopy. Pineal gland volume was estimated using the Cavalieri Method. Additionally, the total number of pinealocytes was estimated using the optical fractionator technique. Pineal gland volume displayed statistically significant changes between lactation and after weaning periods. A significant increase in pineal gland volume was observed from post-natal day 10 to post-natal day 90. The numerical density of pinealocytes became stabilized during lactation and decreased rapidly after weaning. However, the total number of pinealocytes continuously increased during post-natal life of all rats in the study. However, this increment was not statistically significant when comparing the lactation and after weaning periods. The increase in post-natal pineal gland volume may depend on increment of immunoreactive fibres, capsule thickness or new synaptic bodies.  相似文献   

8.
The response of the adrenal cortex to low temperature in relation to the length of the exposures is studied. The morphological changes of the adrenal cells, mainly in the Zona fasciculata, are examined. Thirty white rats of both sexes, divided into six groups, were exposed during time intervals of different lengths to temperatures ranging between – 12° and – 15°C. The cellular modifications encountered by means of the electron microscope at the level of the mitochondria, the smooth endoplasmic reticulum and the liposomes are analyzed and compared with the functional situation of the gland in an effort to establish the existence of a correlation between the morphology and the function.  相似文献   

9.
The morphology and histology of the cetacean adrenal gland are poorly understood. Therefore, this study examined 32 pairs of adrenal glands from 18 pan-tropical spotted dolphins (Stenella attenuata) and 14 spinner dolphins (Stenella longirostris). In both species, the cortex was pseudolobulated and contained a typical mammalian zonation. Medullary protrusions (0-3 per section) and a medullary band were identified in both species. For S. attenuata, no statistical differences were found in the cortex to medulla (CM) ratio or the percent cross-sectional area (PCA) of the adrenal glands compared with sex or sexual maturity. The mean CM ratio for S. attenuata was 2.34 and the PCA was 64.4% cortex, 29.4% medulla and 6.2%'other'. 'Other' indicates blood vessels, connective tissue and the gland capsule itself. For S. longirostris, there was no statistical difference in the CM ratio compared with sexual maturity. However, a statistical difference was found between the CM ratio and sex, suggesting sexual dimorphism (female CM ratio = 2.46 and males = 3.21). No statistical differences were found in the PCA of S. longirostris adrenal glands by sexual maturity. However, a statistical difference was found between the PCA by sex. Female S. longirostris adrenal glands consisted of 65.0% cortex, 27.3% medulla and 7.7% 'other', whereas male adrenal glands consisted of 71.7% cortex, 22.7% medulla and 5.6% 'other'.  相似文献   

10.
Studies of the general histopathology of the fatty liver and kidney syndrome in chickens have shown abnormal accumulations of the lipid in a variety of organs but no degenerative or inflammatory reactions. Lipid was found in some skeletal muscles, alimentary tract, autonomic ganglia, central nervous system and pineal gland as well as in the liver, kidney and heart. Small amounts of lipid were sometimes seen in the exocrine pancreas, adrenal medulla and epithelium of the thyroid follicles. Lipid deposits in the liver were primarily associated with the hepatic structural unit. The glycogen content of the hepatic cell was reduced. The lipid-metabolising gastrocnemius muscle contained abnormal amounts of lipid but this did not apply to the carbohydrate-metabolising pectoralis major muscle. The thymus did not contain excessive lipid but was significantly smaller in affected than in control birds of similar ages. There was loss of tinctorial distinction between the cortex and medulla of the adrenal gland associated with decreased basophilia of the latter region. Many of these morphological changes can be correlated with previously reported biochemical findings and they are discussed in relation to the hyperlipaemia and hypoglycaemia which characterise the disease.  相似文献   

11.
The immunohistochemical (IHC) localization of oestrogen receptor alpha (ERα) was studied in the developing left ovary of 14.5-day-old chick embryos. The study was focused in particular on distinguishing in cortex and medulla the different cell categories that proved positive to the reaction, in order to gain further understanding of gonadal cell interactions during ovarian development. Immunostained cells were observed in both the cortex and medulla, but the reactivity for ERα was discontinuous, probably due to variable cell requirements. In the cortex, positivity was observed in cells of the ovarian surface epithelium, in germ cells and in prefollicular cells. In the medulla, positivity was found in the following cell categories: interstitial cells, poorly differentiated somatic cord cells, including those delimiting lacunae, germ cells and their accompanying cells of epithelial origin. Furthermore, the IHC results showed that the intracellular localization of the antigen was cytoplasmic, nuclear, or both. The significance of ERα presence and intracellular localization was discussed in relation and as supplementary to previous research by various Authors. In particular, as regards the unusual cytoplasmic immunoreactivity, a gradual shift of ERα localization from cytoplasmic to nuclear during the embryonic period is suggested.  相似文献   

12.
The distribution patterns of acetylcholine esterase positive nerve fibers in the goat adrenal gland is described. Some positive cells are observed within the capsule. Terminals were identified in both the medulla and the cortex of the gland.  相似文献   

13.
果子狸甲状腺、肾上腺、脑垂体形态结构的研究   总被引:6,自引:0,他引:6  
通过对果子狸的甲状腺、肾上腺、脑垂体形态结构的显微特征进行观察,结果表明,甲状腺滤泡上皮较薄;肾上腺皮质区内的多形带细胞成团状排列,髓质区的中央静脉管腔大,管壁厚薄不一;脑垂体远侧部的嗜酸性细胞主要分布于中央,嗜碱性细胞主要分布于四周,两者比例接近11。  相似文献   

14.
To elucidate the relationship between steroidogenic hormones and developing adrenal glands, we investigated the immunolocalization of steroidogenic enzymes in equine fetal adrenal glands during mid-late gestation. Fetal adrenal glands were obtained from three horses at 217, 225 and 235 days of gestation. Steroidogenic enzymes were immunolocalized using polyclonal antisera raised against bovine adrenal cholesterol side-chain cleavage cytochrome P450 (P450scc), human placental 3beta-hydroxysteroid dehydrogenase (3betaHSD), porcine testicular 17alpha-hydroxylase cytochrome P450 (P450c17) and human placental aromatase cytochrome P450 (P450arom). Histologically, cortex and medulla cells were clearly observed in the three fetal adrenal gland tissue samples. P450scc and P450c17 were identified in cortex cells close to medulla cells and in some medulla cells in the fetal adrenal glands. P450arom was present in both cortex and medulla cells in the fetal adrenal glands. However, 3betaHSD was not found in any of the equine fetal adrenal gland tissue samples. These results suggest that equine fetal adrenal glands have the ability to synthesize androgen and estrogen, which may play an important physiological role in the development of equine fetal adrenal glands.  相似文献   

15.
Chromogranin A (CgA) is an acidic glycoprotein that is co-stored with hormones or neurotransmitters in granular components of endocrine cells and neurons, and released together with them in response to adequate stimulation. In addition to acting as a packaging protein, CgA functions as a precursor molecule that yields several bioactive peptides by proteolytic cleavage. The purpose of this study is to elucidate how different the processing of CgA is among endocrine tissues by immunostaining using multiple region-specific antisera, and to evaluate the availability of region-specific antisera. When various endocrine organs of rats were immunostained with four region-specific antisera against rat CgA (CgA 1-28, 94-130, 296-314, and 359-389), all amine/peptide-secreting endocrine tissues except the pineal body were stained positively. The adrenal medulla and gastric endocrine cells were equally intensely immunoreactive to all four antisera, while the other endocrine tissues, represented by pancreatic islets, showed different staining patterns depending on the antiserum. These results suggest that the processing of CgA differs from tissue to tissue. An antiserum against horse CgA 335-365, corresponding to rat CgA 359-389 which shows the highest concentration in the plasma and urine of the rat, again stained all endocrine tissues of the horse except the pineal body. Therefore, the anti-horse CgA 335-365 serum is useful for immunohistochemical survey of horse CgA, and may make possible the establishment of a CgA assay system for the measurement of CgA in the plasma, urine and saliva.  相似文献   

16.
We performed 3D reconstruction of the microscopic structure of the adrenal medulla of the adult rats using serial histological sections with histochemical differentiation of adrenaline-storing (A) and noradrenaline-storing (NA) cells. Medulla volume is 1.18 ± 0.17 mm3. Chromaffin tissue consists of 82.9 ± 2.6% of A and 17.1 ± 2.6% of NA cells. Cords of the chromaffinocytes run along the nerves in the adrenal cortex and form cones when merging with medulla bulk. There is no unambiguously greater prevalence of A cells over NA in the areas of the medulla bordering on the cortex as compared to deep layers of medulla. NA cells form a network of beams. Their concentration increases with distance from the entry site of the nerves and is maximal on the opposite side. This testifies to the fallacy of the point of view about the disordered distribution of NA cells in the medulla. Based on the polar asymmetric arrangement of the adrenal chromaffin tissue, if it is necessary to completely remove the medulla with the keeping or reimplantation of the cortex, the subcapsular cortex zone located on the pole opposite to the entrance of nerves should be chosen. In addition, comparable results in the stereological examination of the medulla can be obtained only if taking its areas similar in location. The pronounced relationship in the arrangement of A and NA cells with nerves clearly indicates that in vivo nerve factors play a key role in differentiation and stabilization of the A and NA cells phenotypes.  相似文献   

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18.
A study of the pineal gland of adult male blossomheaded parakeets was conducted with the aid of light microscopic examination to determine the influence of stress on pineal cells. It was demonstrated that stress decreased the growth and activity of the pinel cells when induced as hyperosmolality (water deprivation, salt ingestion). This influence on the pineal gland was not inhibited by previous treatment of a sympatholytic agent, 6-hydroxydopamine.  相似文献   

19.
应用光镜和透射电镜观察,恒河猴肾上腺皮质可分为球状带、束状带和网状带。其特点是:(1)被膜较发达,有时可伸入球状带将其细胞分隔为团块。(2)球状带有时呈指状指入束状带和网状带,其内可见嗜铬细胞;球状带细胞可分为明、暗2种类型,他们排列成团球状、滤泡状、索状和不规则形。(3)网状带较发达,有的可分为内、外2个区;有时网状带呈刺状伸入束状带;有时网状带细胞可见于被膜下或髓质内。(4)有时部分被膜连同皮质一起呈指状伸入髓质内。(5)皮质细胞均含丰富的溶酶体、线粒体和内质网,但不同部位的细胞所含的脂滴在数量、大小、形态和电子密度等方面存在差异。  相似文献   

20.
Age-dependent variations in the immunolocalization of fibronectin (FN) in the thymus were investigated in 1-, 6-, 12- and 20-month-old male and female Swiss albino rats (Rattus rattus) at the light-microscopic level and the changes with ageing in the histological structure of the thymus were also studied. There were no significant differences in the age-dependent variations in the immunolocalization of fibronectin or in the histological structure of the thymus between male and female rats of the same age but there were increases with ageing in the fibronectin content of the thymic capsule, the connective tissue between the lobules, around blood vessels, and in the medulla and cortex of thymus. The connective-tissue content between lobules, fat cells, Hassall's corpuscles, the thickness of capsule and the ratio of the medulla to the cortex of the lobules showed age-dependent increases in the thymus of rats of both sexes. Decreases in the organ weight/body weight ratio were also observed with ageing.  相似文献   

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