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1.
Pregnant rats have been injected intramuscularly with hydrocortisone-acetate or desoxycorticosterone-acetate (DOCA) for the III or the II-III trimesters of pregnancy. In the last case the animals are given not only greater doses of the hormones, but during a longer period. By the end of the pregnancy the drug dose decreases. In mother-rats after hydrocortisone injections the adrenals mass increases; after DOCA the body mass increases, and that of the adrenals drops. In the offspring hydrocortisone produces decline of the thymus and adrenals mass, as well as neutrophilic leucocytosis, lympho-, eosino-++- and monocytopenia. Just the opposite, DOCA results in lympho- and monocytosis, in increasing morphofunctional activity of monocytes. Common effects in hormonal action is demonstrated as underdevelopment of the adrenals, in decreasing thymus mass, in development of neutrophilic leucocytosis and eosinopenia. With increasing doses and duration of prenatal injections of corticosteroids in rats the mass of the adrenals and thymus drops even greater, stimulating effect of the hormones on the neutrophilic granulocytopoiesis decreases.  相似文献   

2.
Structure of the thymus has been studied in offspring of rats subjected to a prolonged forced alcoholization. A decrease in the part of mitotic figures, blasts, small lymphocytes, increasing amount of destroying cells and active phagocyte macrophages have been revealed at counting the cells at light optic level. Certain changes of morphofunctional state of the reticuloepithelial cells, containing vacuoles and large intracellular cavities, lined with microvilli have been detected. Presence of granule-containing endocrine-like cells and plasmocytes, increasing permeability of capillaries have been noticed. Absolute and relative mass of the thymus in the experimental offspring is lower in comparison with that of the normal ones. The changes revealed in morphogenetic processes of the thymus of the newborn rats are evidently related with alterations in the neuro-endocrine status in the functional system mother-fetus.  相似文献   

3.
Histometrical evaluation of the testis was performed in 36 Piau pigs from birth to 16 mo of age to investigate Sertoli cell, Leydig cell, and germ cell proliferation. In addition, blood samples were taken in seven animals from 1 wk of age to adulthood to measure plasma levels of FSH and testosterone. Sertoli cell proliferation in pigs shows two distinct phases. The first occurs between birth and 1 mo of age, when the number of Sertoli cells per testis increases approximately sixfold. The second occurs between 3 and 4 mo of age, or just before puberty, which occurs between 4 to 5 mo of age, when Sertoli cells almost double their numbers per testis. The periods of Sertoli cell proliferation were concomitant with high FSH plasma levels and prominent elongation in the length of seminiferous cord/tubule per testis. Leydig cell volume increased markedly from birth to 1 mo of age and just before puberty. In general, during the first 5 mo after birth, Leydig cell volume growth showed a similar pattern as that observed for testosterone plasma levels. Also, the proliferation of Leydig cells per testis before puberty showed a pattern similar to that observed for Sertoli cells. However, Leydig cell number per testis increased up to 16 mo of age. Substantial changes in Leydig cell size were also observed after the pubertal period. From birth to 4 mo of age, germ cells proliferated continuously, increasing their number approximately two- to fourfold at each monthly interval. A dramatic increase in germ cells per cross-section of seminiferous tubule was observed from 4 to 5 mo of age; their number per tubule cross-section stabilized after 8 mo. To our knowledge, this is the first longitudinal study reporting the pattern of Sertoli cell, germ cell, and Leydig cell proliferative activity in pigs from birth to adulthood and the first study to correlate these events with plasma levels of FSH and testosterone.  相似文献   

4.
The state of the sensomotor cortex in the offspring of white non-inbred rats, "passively" smoking before mating, during mating and throughout pregnancy time has been investigated. The investigation performed in 14 age groups from the period of birth up to a relative morphological stability (age of 3 months), control and experimental rats (as a whole 281 animals) makes it possible to conclude that certain components of the tobacco smoke are accumulated in the offspring blood and continue to exercise a destructive influence on the neocortex during 2 weeks after birth. The consequence of chronic intoxication of the tobacco smoke through the system mother--fetus is expressed as diffuse and focal decrease of neurons nearly by 1/3 in the sensomotor cortex, especially in the V cytoarchitectonic layer.  相似文献   

5.
Developmental changes in the cellular composition of the chicken thymus   总被引:2,自引:0,他引:2  
The cellular composition of the chicken thymus has been analyzed at different ages by using size distribution analysis in combination with preparative cell electrophoresis. The combination of these two physical methods was able to clearly resolve two major cellular subpopulations in the young chicken thymus and suggested the exsistence of a third one. Microscopically, all three cell types appeared to be small lymphocytes. Medium and large lymphocytes are not detected as distinct peaks by the settings used.The analysis revealed dramatic developmental changes in the cellular composition of the thymus. The adult chicken thymus, which is known to have practically no cortex, contained mainly one relatively large cell type. This cell type may, therefore, represent the medullary lymphocyte and may be active in graft-versus-host (G.v.H.) reactions. In the early postnatal thymus that is known to contain little graft-versus-host reactivity this larger cell type was not detectable. Instead, smaller cell types were found to be dominant. The developmental shift from smaller to larger cells was discontinuous. Before thymus involution at 16 weeks of age, smaller and larger cells were both found to be present and to have the same typical size and electrophoretic mobility that is characteristic for the postnatal or the adult chicken thymus, respectively. Size and electrophoretic mobility were therefore taken as markers indicating distinct cellular subpopulation in the thymus.  相似文献   

6.
Mesenteric lymph nodes in fetuses and offspring of white rats have been studied during various age periods after indomethacin injection in doses 2.5 mg/kg and 1 mg/kg daily from the 18th up to 21st day of pregnancy. Dose-dependent retardation in formation of main structures of the mesenteric lymph nodes, decreasing amount of the lymphoid type cells have been revealed. Retardation in the capsule, sinuses and reticular fibers of the node takes place, as well as decrease in lympho- and plasmocytopoiesis. It is more pronounced after indomethacin in dose 2.5 mg/kg. Simultaneously, formation of the cerebral substance and appearance of lymphoid nodules and their germinative centers are delayed. After the drug effect (2.5 mg/kg), up to the age of 2 weeks the amount of tissue basophils and eosinophilic granulocytes decreases. When the dose of the drug is 1 mg/kg decreasing amount of these cells is substituted for their compensatory increase on the 2d-3d week. The data obtained demonstrate a decreasing function of the lymph nodes, that depends on the dose of indomethacin.  相似文献   

7.
Sandelius, A. S. and Liljenberg, C. 1982. Light-induced changes in the lipid composition and ultrastructure of plastids from potato tubers. – Physiol. Plant. 56: 266–272.
Amyloplasts and starch containing plastids from green tissue – amylochloroplasts – from potato tubers ( Solanum tuberosum L., var. King Edward) were separated from other cell organelles by sedimentation in a discontinuous sucrose gradient. Their lipid composition was analysed with emphasis on galactolipids and phospholipids and the fatty acid compositions of these lipids. Irradiation of the tubers caused increased ratios of monogalactosyl diacylglycerol to digalactosyl diacylglycerol and of total galactolipids to total phospholipids in the plastid membranes. Furthermore, the degree of unsaturation of the fatty acids increased in all lipid classes analysed, this effect being most prominent in the galactolipids. The ultrastructural studies made on tuber tissue revealed that irradiation caused a change in starch grain size distribution concomitant with formation of membrane structures resembling grana within the envelope. In many cases prolamellar bodies and plastoglobuli were present.  相似文献   

8.
F J Weaker  I L Cameron 《Cytobios》1977,19(74):79-91
The chromatin fibres of the male gamete nucleus of Dasypus novemcinctus contain fibrils. Measurements indicate that the chromatin fibre diameter and the number of fibrils within the fibre increase, whereas the diameter of the fibrils decreases during spermiogenesis. It is suggested that the fibrils represent a DNA-protein complex. It is further suggested that the increased fibre diameter, and the increased number of fibrils correlates with the formation of larger fibres during the condensation of the spermatid nucleus, whereas the decrease in fibril diameter is correlated with the replacement of histones with new low molecular weight acid-soluble proteins.  相似文献   

9.
BACKGROUND: Sex steroids affect many peripheral tissue sites in female mammals. Receptors for these hormones have been found in skin, fat, and bone. In women, these tissues can show morphological changes during the menstrual cycle that may be directly related to steroid secretion. METHODS: The present study was done on chimpanzees to document morphometric markers associated with these tissues (anogenital swelling volume, skin fold thickness as indicator of subcutaneous fat, bony diameters of mandible, wrist, and elbow) and to compare them with cyclic patterns of estradiol, progesterone, testosterone, gonadotropins, and prolactin. RESULTS: Swelling volume changed significantly over the menstrual cycle. All other morphometric parameters showed variation without statistical significance. Skin folds were thickest during the luteal phase. Bony diameters displayed similar but less distinctive changes. Testosterone correlated positively with diameter sites, inversely with subcutaneous fat. No relationships with either estradiol or progesterone were found. We assume that subcutaneous fat and morphometric bone parameters exhibit cycle-dependent changes that may be caused by changes in steroid secretion.  相似文献   

10.
Changes have been revealed in the function of cyclic GMP system of thymus and liver of irradiated (8 Gy) mice. In the thymus the cGMP level increased during the first 60 min following irradiation. In the liver the concentration of cGMP exhibited two peaks: 30 min and 24 hr after irradiation. The changes observed in the cGMP level are connected with the increased guanylate cyclase activity of thymocytes and liver of irradiated mice and, less likely, with changes in the activity of cGMP phosphodiesterase of these tissues.  相似文献   

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13.
The cuticle of the free-living nematode Caenorhabditis elegans is a proteinaceous extracellular structure that is replaced at each of four postembryonic molts by the underlying hypodermis. The cuticles of the adult and three juvenile stages (L1, Dauer larva, L4) have been compared ultrastructurally and biochemically. Each cuticle has an annulated surface and comprises two main layers, an inner basal layer and an outer cortical layer. The adult cuticle has an additional clear layer which separates the basal and cortical layers and is traversed by regularly arranged columns of electron-dense material. The fine structure of the cortical layer is similar in cuticles from different stages while that of the basal layer is stage specific. Purified cuticles were obtained by sonication and treatment with sodium dodecyl sulfate (SDS) and their component proteins solubilized with a sulfhydryl reducing agent. The degree of cuticle solubility is stage specific and the insoluble structures for each cuticle were localized by electron microscopy. Analysis of 35S-labeled soluble cuticle proteins by SDS-polyacrylamide gel electrophoresis yields unique banding patterns for each stage. Most proteins are of high molecular weight (100–200 K) and are restricted to particular stages. Sixteen of the nineteen major proteins characterized are specifically degraded by bacterial collagenase. The results indicate that the different molts are not reiterative, but require the integration of both unique and shared gene functions. The potential use of stage-specific cuticle differences to identify and characterize regulatory genes controlling cuticle-type switching during development is discussed.  相似文献   

14.
15.
Immunization is performed with 20% of water-saline extract of medulla oblongata on the 6th, 8th, 10th days of pregnancy (1 g per 200 g body mass). In the thymus cortical substance of newborn rats no statistically significant difference in content of small lympocytes, lymphoblasts and large lymphocytes, mitotically deviding cells is revealed as compared to the normal. The part of middle lymphocytes decreases up to 5.7 +/- 0.7% (control--10.0 +/- 1.7%). The content of distroying cells and fagocytic macrophages is increasing. In cytoplasm of one macrophage several fagocyted degenerating cells with pyknotic nuclei and destructively altered organells are often present. In the interlobular connective tissue an increased amount of degenerating forms of mast cells is noted. In the thymus medullary substance small lymphocytes are growing in number. Certain changes in vessels of the microcirculatory bed are revealed.  相似文献   

16.
Serotonin (5-HT) contributes to the prenatal development of the central nervous system, acting as a morphogen in the young embryo and later as a neurotransmitter. This biologically active agent influences both morphological and biochemical differentiation of raphe neurons, which give rise to the descending serotonergic paths that regulate the processing of acutely evoked nociceptive inputs. The involvement of 5-HT in the prenatal development of tonic nociceptive system has not been studied. In the present study we evaluated the effects of a single injection (400 mg/kg, 2 ml, i.p.) of the 5-HT synthesis inhibitor, para-chlorophenylalanine (pCPA), given to pregnant rats during the critical period fetal serotonin development. The functional integrity of the tonic nociceptive response was investigated in 25 day old rats using the classic formalin test. Morphological analysis of brain structures involved in formalin-induced pain and 5-HT levels in the heads of 12-day embryos were also evaluated. Embryonic levels of 5-HT were significantly lowered by the treatment. The juvenile rats from pCPA-treated females showed altered brain morphology and cell differentiation in the developing cortex, hippocampus, raphe nuclei, and substantia nigra. In the formalin test, there were significant decreases in the intensity and duration of the second phase of the formalin-induced response, characterizing persistent, tonic pain. The extent of impairments in the brain structures correlated positively with the level of decrease in the behavioral responses. The data demonstrate the involvement of 5-HT in the prenatal development of the tonic nociceptive system. The decreased tonic component of the behavioral response can be explained by lower activity of the descending excitatory serotonergic system originating in the raphe nuclei, resulting in decreased tonic pain processing organized at the level of the dorsal horn of the spinal cord.  相似文献   

17.
Follicle maturation in the ovary of sexually mature domestic geese in the spring reproductive cycle was investigated by histological methods and steroid-RIA. The single-layer granulosa of primary follicles temporarily transformed in the growing white follicles into several layers or a simple membrana granulosa with nuclei at several different levels in the cell. In the yolky follicles the granulosa represents a cuboidal epithelium (F4-F3) and subsequently a high cylindrical epithelium (F1). The originally connective tissue-like cells of the theca interna show a glandular proliferation in the largest white (F7) and the small yolky follicles (F6-F5). Glandular cell nests in the theca externa are typical in the generation of small white follicles and are absent in the wall of yolky follicles. Progesterone-content in the follicular wall (granulosa + theca) is the highest in the F1-F2 and F6-F5 types and is low in small white follicles (F8, F9 and F10). E2 concentration shows only slight variations between F1-F10. TEST content shows a slight increase between F1 and F3 and is high in medium-sized white follicles (F8-F9). The results suggest that in addition to the granulosa, the theca interna is also capable of an intensive progesterone synthesis.  相似文献   

18.
Using sera containing antibodies to antigens of epithelial reticular cells it is possible to detect by immunofluorescence early stages of organ accidental involution and to trace parenchyma demasking that results from lymphocyte migration upon injection of prednisolone, azathioprin or their combinations. Prior to the drug administration only certain short thin processes of epithelial cells masked by a great number of lymphoid elements are detectable in the cortical zone of the thymus. Injection of 10-40 mg/kg prednisolone, 100-200 mg/kg azathioprin or their combinations causes stable different-degree demasking of the epithelial reticulum seen during immunofluorescence as a network of fluorescent processes. Administration of drug combinations also causes marked attenuation of the reaction, probably resulting from dystrophic changes in thymic epithelial cells.  相似文献   

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20.
R Winand  D Luzzati 《Biochimie》1975,57(6-7):764-771
A technique for the preparation of plasma membrane from a skeletal muscle myogenic cell culture is described. Electron microscopic and enzymatic studies indicate that the preparation has kept its morphological integrity and has negligeable amount of cellular contiaminants. Carbohydrate composition studies have shown that the differentiated cells contain less hexosamine and sialic acid but accumulate glucose and galactose; the latter increase reflects the presence of a glucose-galactose-hydroxylysine unit which appears at the cell surface when myoblasts reach confluency.  相似文献   

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