Assuntos
Músculos/ultraestrutura , Junção Neuromuscular/fisiologia , Sinapses/ultraestrutura , Triclorfon/intoxicação , Animais , Diafragma/efeitos dos fármacos , Diafragma/ultraestrutura , Feminino , Técnicas In Vitro , Masculino , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/ultraestrutura , Músculos/efeitos dos fármacos , Junção Neuromuscular/ultraestrutura , Ratos , Músculos Respiratórios/efeitos dos fármacos , Músculos Respiratórios/ultraestrutura , Sinapses/efeitos dos fármacosRESUMO
A comparative analysis of changes in ultrastructure of neuro-muscular synapses of three types has been studied in the rat diaphragmal muscle at an acute poisoning with chlorophos. A high stability to the damaging action of chlorophos in white muscle fibers has been revealed in comparison with other types. The most essential changes of the ultrastructure have taken place in slow intermediate fibers. These differences are evidently connected with certain peculiarities in morphofunctional organization of calcium-sequestring ++ components of three types of muscle fibers (sarcotubular system, mitochondria) and presence of parvalbulin.
Assuntos
Diafragma/inervação , Modelos Animais de Doenças , Mitocôndrias Musculares/ultraestrutura , Sarcômeros/ultraestrutura , Sinapses/ultraestrutura , Triclorfon/intoxicação , Doença Aguda , Animais , Microscopia Eletrônica , RatosRESUMO
A study was made of the ultrastructure of epithelial cells of the rat proximal tubules nephrons 25-30 seconds, and 15 and 30 minutes following penicillin injection. The morphological changes in the transporting cells that were observed involved the dilation of the inner cavities of canals and cisterns of the endoplasmic reticulum. The number of elements of the smooth endoplasmic reticulum concentrated on the periphery of the cell, near the basolateral border, was seen to increase. Microbodies appeared enlarged with the appearance of the nucleolus; the electron density of the cytoplasmic ground substance fell down. The space between cells augmented, and the interstitial space between infoldings of the basal plasmalemma was much broadened. Similar morphological changes but different in the intensity were found at either stage examined. The maximum changes were established 25-30 seconds following penicillin injection.
Assuntos
Túbulos Renais Proximais/ultraestrutura , Penicilinas/farmacologia , Animais , Células Cultivadas , Epitélio/efeitos dos fármacos , Epitélio/ultraestrutura , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Microcorpos/ultraestrutura , Penicilinas/farmacocinética , RatosRESUMO
Scanning electron microscopy of blood clots of 6 patients with hemolytic disease of newborn has shown specific large ball-shaped red cells with small round excrescences on their surface. After hemosorption the number of such excrescences reduces but a great number of deformed cells appears. In experimental hemolysis of healthy newborns' blood no such excrescences have been detectable on the red cell surface.
Assuntos
Eritroblastose Fetal/sangue , Membrana Eritrocítica/ultraestrutura , Trombose/sangue , Humanos , Técnicas In Vitro , Recém-Nascido , Microscopia Eletrônica de VarreduraAssuntos
Acetilcolina/farmacologia , Sanguessugas/ultraestrutura , Neurônios/ultraestrutura , Serotonina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/ultraestrutura , Sanguessugas/efeitos dos fármacos , Microscopia Eletrônica , Neurônios/efeitos dos fármacos , Neurônios/metabolismoRESUMO
A 24-hour electron microscopic examination of neuronal and capillary ultrastructure in sensorimotor complex was performed after whole-body neutron irradiation of mature rats in the dose of 10 Gy. The results suggest that postradiation neuronal changes, observed for 6 hours after irradiation, are mainly caused by direct effect of ionizing radiation. At later terms this process is influenced by blood capillary lesions. The effect of neutron irradiation at the ultrastructural level is similar to that of rarely ionizing radiation.
Assuntos
Córtex Cerebral/ultraestrutura , Nêutrons , Lesões Experimentais por Radiação/patologia , Doença Aguda , Animais , Capilares/efeitos da radiação , Capilares/ultraestrutura , Córtex Cerebral/irrigação sanguínea , Masculino , Dilatação Mitocondrial/efeitos da radiação , Ratos , Ratos Endogâmicos , Fatores de Tempo , Irradiação Corporal TotalRESUMO
A combined action of acetylcholine and serotonin is demonstrated to produce, in ultrastructure of the Retzius neuron of the leech, changes similar to those resulted from synaptic activation. Nevertheless, acetylcholine alone produces much deeper morphological shifts. A conclusion is made that serotonin not only retards impulse activity of the neuron, but it "slows down" development of rather great changes in its ultrastructure.
Assuntos
Acetilcolina/farmacologia , Gânglios/efeitos dos fármacos , Serotonina/farmacologia , Animais , Interações Medicamentosas , Gânglios/citologia , Técnicas In Vitro , Sanguessugas , Microscopia Eletrônica , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Transmissão SinápticaRESUMO
Ultrastructural changes of the rat diaphragm muscle fibers and electron histochemical distribution of calcium ions were studied following chlorophos administration in 5, 15 and 45 minutes (dose - 300 mg/kg, intraperitoneally). The local swelling of mitochondrial matrix and the appearance of contractures were found first in postsynaptical region. Then the postsynaptical alterations increased; the swelling and fragmentation of sarcoplasmic reticulum were observed in addition to desorganization of mitochondrial ultrastructure. Granules of the histochemical product were revealed in mitochondria, in the sarcoplasmic reticulum and in filaments. Changes in distribution of calcium ions in the rat diaphragm muscle fibres after chlorophos administration and the role of Ca++ the in the mechanism of muscle alteration discussed.
Assuntos
Cálcio/metabolismo , Inibidores da Colinesterase/farmacologia , Músculos/ultraestrutura , Triclorfon/farmacologia , Acetilcolinesterase/metabolismo , Animais , Diafragma/efeitos dos fármacos , Diafragma/metabolismo , Diafragma/ultraestrutura , Feminino , Histocitoquímica , Masculino , Músculos/efeitos dos fármacos , Músculos/metabolismo , Ratos , Fatores de TempoRESUMO
At early times (15 min to 6 h) after whole-body gamma-neutron irradiation of mature rats with a dose of 10 Gy reactive changes occur in neurons of the sensimotor cerebral cortex which can be interpreted as a manifestation of the enhancement of functional and metabolic activity of nerve cells followed by inhibition thereof.
Assuntos
Córtex Motor/efeitos da radiação , Neurônios/efeitos da radiação , Nêutrons , Córtex Somatossensorial/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Raios gama , Masculino , Microscopia Eletrônica , Córtex Motor/ultraestrutura , Neurônios/ultraestrutura , Ratos , Ratos Endogâmicos , Córtex Somatossensorial/ultraestrutura , Fatores de TempoRESUMO
Ultrastructural changes of rat diaphragm muscle fibers were studied after administration of chlorophos, i. e. organophosphorus inhibitor. Observations were made 10-180 seconds after treatment (concentrations--18 and 24 mM). The swelling of mitochondria and the increase in the length of sarcomeres were observed simultaneously. These changes were phasic. The swelling of mitochondria is probably due to the increase in energetical activity of muscle fibres.
Assuntos
Músculos/efeitos dos fármacos , Triclorfon/toxicidade , Animais , Diafragma , Relação Dose-Resposta a Droga , Feminino , Masculino , Microscopia Eletrônica , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/ultraestrutura , Dilatação Mitocondrial/efeitos dos fármacos , Músculos/ultraestrutura , Ratos , Sarcômeros/efeitos dos fármacos , Sarcômeros/ultraestrutura , Fatores de TempoRESUMO
It was established that the ultrastructure of blood capillaries of the brain changes during the first six hours following whole-body neutron irradiation of rats (10 Gy) which was indicative of the capillary wall swelling, the increase in the microcirculatory bed permeability, and pericapillary edema development. Those processes seemed to be reversible since during this period no severe destructive changes were detected in the microvessel wall.
Assuntos
Córtex Cerebral/irrigação sanguínea , Lesões Experimentais por Radiação/patologia , Irradiação Corporal Total , Animais , Córtex Cerebral/efeitos da radiação , Masculino , Microcirculação/efeitos da radiação , Microcirculação/ultraestrutura , Microscopia Eletrônica , Nêutrons , Ratos , Ratos EndogâmicosRESUMO
Distribution of calcium ions in the rat diaphragm muscle fibers has been studied electron histochemically using various fixation techniques and chemical treatment of the tissue. When potassium pyroantimonate in water solution is used after a short perfusate fixation with aldehydes, the reaction product granules are revealed in mitochondria, in the disk I, in the center of the disk A, more seldom the precipitate is found in the sarcoplasmic reticulum (SR) and in the T-system. The presence of calcium ions in the precipitate is proved by means of treatment the preparations with ethylenglycol- and ethylen-diamine-tetra-acetic acids. When contracture is resulted from potassium rhodanide administration, in mitochondria the reaction product granules decrease in their number, the precipitate disappears from the central part of the disk A, while the number of the granules increases in the SR terminal cisterns. The data obtained are compared with calcium ions distribution observed at the freezing-substitution method without an additional chemical fixation, as well as the histochemical fixations after Oschman method and at a usual fixation with OsO4. Certain similarity is revealed in distribution of the calcium pyroantimonate granules at aldehyde fixation and when the freezing-substitution method is used.
Assuntos
Cálcio/metabolismo , Músculos/ultraestrutura , Junção Neuromuscular/ultraestrutura , Animais , Meios de Cultura , Diafragma , Histocitoquímica , Técnicas In Vitro , Microscopia Eletrônica , Contração Muscular , Músculos/metabolismo , Ratos , Manejo de EspécimesRESUMO
Localization and distribution of the gap junctions in the human epidermis have been studied. They are mainly concentrated in the area of biologically active (acupunctive) points and in so called meridians connecting these points. A supposition is made that the gap junction system performs certain integration of the information from the skin surface and its aneural transmission to remote areas. Discovery of a regulated gap junction system in relatively low organized animals (previously described by the authors), as well as revealing of such a system in mammals, makes it possible to suppose that the system is phylogenetically the most ancient one performing a directed transmission of an information simultaneously with and besides the neural system.
Assuntos
Comunicação Celular , Junções Intercelulares/citologia , Pele/citologia , Técnicas Citológicas , Condutividade Elétrica , Feminino , Humanos , Junções Intercelulares/fisiologia , Masculino , Fenômenos Fisiológicos da PeleRESUMO
Combined study of 48 postmortem observations of cerebral lesions caused mainly by meningococcal infection in children was carried out. In 15 cases, isolated subclinical involvement of the brain (more frequently, of the vascular plexus and meninges) caused by influenza A viruses (8 cases), B (2 cases), adenoviruses (6), parainfluenza and respiratory syncytial virus (1 each), and chlamydia (2) was found. This was proved by the presence of the appropriate antigens in the brain revealed by immunofluorescence which were absent in respiratory organs, high titres of antibody to the same agents in the cerebrospinal fluid which were lacking in 13 cases or had significantly low titres in 2 cases in the blood, virus isolation from the brain (2 cases) and detection of virus particles in 1 out of 2 cases from which the vascular plexus was examined by electron microscopy. Histological examination of the affected areas revealed structural changes of ependymocytes which were principally similar to those described in respiratory organs as well as in other organs in cases of generalization of respiratory infections. Different degrees of sclerosis of vascular plexus (2 cases) or meninges (2 cases) were also observed.