RESUMO
By means of scanning electron microscopy of native and corrosive preparations peculiarities of endocardium of the papillary-trabecular apparatus of the human heart ventricle and its vessels have been studied in ontogenesis. Folds of the endocardium increase its contact area with blood and also increase reserve of its elasticity at diastole. The subendocardial vascular plexus is formed by capillary-like venous sinusoids. They situate in the direction to the compact myocardium at the depth of 300-500 mcm. They are supposed to perform resorptive functions of nutritive substances and oxygen from blood, which is in the ventricular cavities and to smooth blood pressure between blood in the ventricular cavities and vessels of the compact myocardium.
Assuntos
Vasos Coronários/anatomia & histologia , Coração Fetal/anatomia & histologia , Ventrículos do Coração/anatomia & histologia , Adolescente , Adulto , Fatores Etários , Idoso , Capilares/anatomia & histologia , Capilares/ultraestrutura , Criança , Pré-Escolar , Vasos Coronários/ultraestrutura , Endocárdio/anatomia & histologia , Ventrículos do Coração/embriologia , Humanos , Lactente , Recém-Nascido , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Miocárdio/ultraestruturaRESUMO
By means of scanning electron microscopy of corrosive casts, applied to the human cardiac hemomicrocirculatory bed vessels, beginning from 6-9-month-old fetuses up to persons of elderly and old age, peculiarities in form, dimensions and distribution have been revealed in the wall of the arterial part of the vessels of the hemomicrocirculatory bed of so called circular strips. They are inevitable structural components in the wall of the vessels mentioned and correspond to smooth myocytes, shifted at methylmetacrilate injection.
Assuntos
Envelhecimento , Vasos Coronários/ultraestrutura , Feto/ultraestrutura , Modelos Anatômicos , Adolescente , Adulto , Fatores Etários , Idoso , Arteríolas/ultraestrutura , Criança , Pré-Escolar , Idade Gestacional , Átrios do Coração , Ventrículos do Coração , Humanos , Metilmetacrilato , Metilmetacrilatos , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Pessoa de Meia-IdadeRESUMO
Hearts of 220 human corpses, who had not any cardiovascular system disease during their life, have been distributed into age groups, beginning from fetuses up to old age. By means of injection, silver nitrate impregnation and scanning electron microscopy methods, applied to corrosive preparations, morphological mechanisms of the blood stream regulation in the hemomicrocirculatory bed of the human heart have been revealed in ontogenesis. The first group of the regulation mechanisms includes proper mechanisms inherent in the links of the microbed: spatial orientation of microvessels, precapillary sphincters, anastomoses between these vessels, sequence in arrangement of the endothelial cell nuclei, length, diameter and number of links in the microcirculatory bed. The second group embraces those mechanisms, that depend on structure of the myocardial wall, influencing the microcirculatory bed.
Assuntos
Envelhecimento/fisiologia , Vasos Coronários/crescimento & desenvolvimento , Microcirculação/fisiologia , Miocárdio/ultraestrutura , Vasos Coronários/ultraestrutura , Feminino , Humanos , Masculino , Microscopia EletrônicaRESUMO
Using a complex of morphological techniques both injective and non-injective, scanning electron microscopy including, the hemomicrocirculatory bed and vascular anastomoses have been studied in various parts of the human heart. In most cases anastomoses between the microcirculatory links are realized at the level of capillaries, precapillary arterioles and postcapillary venules. Venulo-venular anastomoses are demonstrated in the myocardium. Existence of terminal arterioles is discussed.
Assuntos
Anastomose Arteriovenosa/anatomia & histologia , Coração/anatomia & histologia , Adulto , Idoso , Feto , Técnicas Histológicas , Humanos , Microcirculação/anatomia & histologia , Microscopia Eletrônica de VarreduraRESUMO
Using a complex approach in studying microcirculatory bed of the human heart, possibilities of scanning electron microscopy of corrosive preparations, those of silver nitrate impregnation after V. V. Kuprianov are demonstrated. The silver nitrate impregnation makes it possible to study the wall structure of the microcirculatory pathways, to analyse arrangement of nuclei in the endothelial and muscle cells of the microcirculatory links, to reveal together with the vessels the surrounding tissues. Scanograms of the corrosive preparations of the arterioles demonstrate "circulatory strips", that are absent in the venular part. The relief of the luminal casts of the microcirculatory bed vessels in the human heart is presented as impresses of nuclei of the endothelial and smooth muscle cells. Peculiarities in form and distribution of these nuclei in various links of the microbed are demonstrated.
Assuntos
Vasos Coronários/anatomia & histologia , Humanos , Microcirculação/anatomia & histologia , Microscopia Eletrônica de VarreduraRESUMO
Seventy-eight hearts from persons, who had not suffered any cardiovascular disorders during their life time, have been studied. Microcirculatory bed vessels are revealed by impregnation with silver nitrate after V. V. Kuprianov. The values of the capillary diameters obtained are mathematically treated using T. H. Bayes formula. Periods of individual development of the heart are defined when a high functional activity of the capillary bed of the auricles and ventricles is noted. Evidently, this is one of the factors contributing to development of the cardiac ischemic disease.
Assuntos
Vasos Coronários/anatomia & histologia , Adolescente , Adulto , Fatores Etários , Idoso , Capilares , Criança , Pré-Escolar , Coração Fetal/anatomia & histologia , Átrios do Coração , Ventrículos do Coração , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-IdadeRESUMO
The microcirculatory bed of various parts of the human bulbar conjunctiva in ontogenesis has been studied in 63 preparations of the eyeball by means of complex morphological methods. Structural peculiarities and functions of all parts of the micro-vessels have been revealed in fetuses, their conjunctiva being not yet subjected to any environmental effect, and in successive age groups of the postnatal development. The period of stabilization and differentiation for all parts of the microcirculatory bed in the eyeball conjunctiva has been stated. Certain age changes of the microcirculatory bed have been revealed in all sectors and in various parts within the sectors; these changes should be taken into account at biomicroscopy and when analysing the data obtained.