Effect of helium-neon laser rays on the vascular and nerve tissue structures of the small intestine in the cat

The influence of laser radiation (Laser LH-75) on the status of tissue elements and microvascular nervous structures of the small intestine in dynamics has been studied on 15 adult cats. It has been established that a daily 6-minute action of laser rays during 15 days causes the hypertrophy of muscular and mucous membranes of the small intestine, persistent dilation of microcirculatory flow of the muscular-intestinal plexus, and also hypertrophy of neurocytes of vegetative ganglia.     

Effect of helium-neon laser on the microcirculation in blood vessels of the rat pia mater

The sensitivity of rat's microvessels of microcirculatory bed of brain's pia matter was studied by helium-neon laser radiation. Changes in the reactivity by the microscopy findings were studied on the 7, 30, 45, 60, 90th days of animals postnatal development. Laser radiation was used during 30 min. Local changes in all components of the microcirculatory bed were fixed. It is mentioned that in adult rat the expressiveness of arteriole's local widening reaction in the radiated place reduces, but the degree of the reduction is below or over the radiated place, on the contrary, increases. The arteriole diameter in 30-day old rats increases to 59% in comparison to the initial level, and 90th day old animals--to 16%. The degree of reaction's expressiveness depends upon the microvessel diameter and the animal's age.     

Vascularization of the myenteric plexus in the small intestine of pigeons]

By means of light and electron microscopy vascularization of the myenteric plexus has been studied in the pigeon small intestine. Ganglia of the plexus, their cell composition, ultrastructure of neurons have been described. Links of the microcirculatory bed of the intramural ganglia are characterized, interrelations of capillaries with neurons are described, quantitative estimation of microhemovessels, surrounding the microcirculatory bed of the myenteric plexus in the intestinal wall in birds and mammalia.     

Morphological characteristics of nerves of the vascular plexuses in the lateral cerebral ventricles of human fetuses

The vascular plexus of the lateral ventricle of the human brain includes the microcirculatory bed responsible for the blood supply and liquor production of the organ. Blood capillaries form a thick parviansiform network of the plexus. Innervation of the vascular plexus of the cerebral lateral ventricle in human embryos and fetuses develops synchronously with formation of the plexus itself. The structural complexity of the nervous apparatus increases at the expense of increasing number of nervous fasciculi and single nervous fibers. By the time of birth the nervous apparatus of the plexus acquires a definitive character. After birth further improvement of the nervous apparatus takes place. The role of the microcirculatory bed and of the nervous apparatus of the vascular plexus in ensuring functional loadings and their participation in reactions to certain pathological effects is substantiated.     

Ultrastructural changes in the microcirculatory bed and filtration-reabsorption barrier of the kidney during temporary ischemia after unilateral nephrectomy

Ultrastructure of cellular elements of the microcirculatory bed and filtration-reabsorption barrier has been studied in 150 mature white rats, in which vascular fasciculus of the left kidney has been compressed for 30 min, 1-2 h with a subsequent restoration of the blood stream in the organ undergone ischemia on the 3rd, 7th, 14th, 30th, 60th, 180th, 360th days under conditions of the preliminarily right kidney nephrectomy. On the 3rd day after ischemia of the remained kidney for 30 min, structural components of the walls of the glomerular arterioles and those of the filtration-reabsorption barrier undergo certain ultrastructural changes, that with time elapsed (7, 14 days) gradually pass away, and amount of cells with hypertrophic processes increases. Ischemia for 1 h in the remained kidney with subsequent restoration of the blood stream on the 3rd, 7th days produces in the structures mentioned more pronounced destructive changes. During subsequent compensatory hypertrophy (the 30th, 60th days) of the remained kidney after its ischemia, in the microcirculatory bed elements and in the convoluted canal epitheliocytes intracellular regenerative and hyperplastic processes develop. However, ischemia for 2 h in the remained kidney produces severe destructive-necrotic phenomena in ultrastructure of the microcirculatory bed and of the filtration-reabsorption barrier.     

Structural changes and hemodynamic relations in the microcirculatory bed of the mesentery of the white rat during the period of sexual maturation

Structural changes and hemodynamic relations have been studied in the microcirculatory bed of the white rat small intestine mesentery during sex maturation (from the 3d up to the 10th week of the postnatal development). All calculations are performed regarding the mesenteric segment limited with two intestinal arteries, which is considered as an elementary microvascular module. Complication of the microcirculatory bed construction takes place at the expense of increasing number (nearly five-fold) of microvessels in the segment and increase of the capillary network density. The hemodynamic factor plays a certain role for stimulating the process of the capillary growth. The definitive structure of the mesenteric microcirculatory bed is completed by the 7th week. The main rearrangement of the microcirculatory system during the developmental process from a simple arterio-venular loop up to a complex microcirculatory bed with a branching capillary network is performed within the limits of the mesenteric segment.     

The effect of subtotal vagotomy of the plexus myentericus (Auerbach) on the function of the intramural nervous system. A quantitative histochemical examination in white laboratory mice]

The effect of a subtotal vagotomy on the function of the intramural nervous system of different parts of the intestinal tract is studied by means of quantitative measurements of the acetylcholinesterase (AChE) activity. By sham vagotomy it was possible to explore the effect of narcosis and laparotomy on the intramural nervous system of the intestine. Vagotomy is followed by a decrease in AChE activity of the ganglionic cells in all parts of the intestinal tract. A minimum of activity, about 50% of the normal concentration, is attained at the 16th postoperative day. After this time, a continual increase in AChE activity, along with a reactivation of the function of the ganglionic cells, can be observed. 90 days after vagotomy the ganglionic cells of the intramural nervous plexus show a normal enzyme activity. These results support the hypothesis that most of the cells of the myenteric plexus build up an autonomic nervous plexus, which is stimulated in an excitatory way by the vagus nerve and which will be inhibited by sympathetic stimulation.     

Effect of intravascular laser irradiation of blood on the status of the adrenergic and cholinergic structures of the small intestine in experimental peritonitis

In the experiment performed on 60 mongrel dogs the effect of intravascular laser radiation of blood (ILRB) to adrenergic and cholinergic fibers of the small intestine has been studied at treatment of experimental generalized suppurative peritonitis. At treatment of the experimental peritonitis by means of traditional method only one month after its termination a positive reaction to acetylcholinesterase (AChE) is noted, structural organization of cholinergic fibers corresponds to the norm, and density of their plexuses increases. Application of ILRB at treatment of the experimental peritonitis facilitates to increasing density of the cholinergic fibers already on the 21st day after termination of the treatment; their AChE increases essentially, their structural organization corresponds to the norm. In cytoplasm of neurons of the muscular-intestinal plexus a positive reaction to AChE is revealed; this demonstrates their increased functional activity. The small intestine adrenergic apparatus at peritonitis undergoes less manifested structural-chemical alterations. After termination of treatment by means of traditional methods it corresponds to the norm on the 7th day, and after ILBR treatment----on the 3d day. Thus, application of ILBR in treatment of the experimental peritonitis enhances the development of regenerative processes in adrenal and cholinergic structures of the small intestine, facilitates a more manifested demonstration of compensatory-reparative possibilities of the organism.     

Function of the microcirculatory system during the long-term regression of the early stages of atherogenesis

Lipid metabolism, intestinal mesentery microcirculatory bed (MCB) and erythrocyte (E) morphology in arterial and venous blood were studied in rabbits with experimental atherosclerosis (the model of N. N. Anichkov) and its spontaneous regression. The interrelation was determined between lipid metabolism (LM), MCB structural and functional disorders and anomalous E form appearance, and to a lesser extent the atheromatosis of the aorta. Microcirculatory (MC) disorders disappeared 12 months later in the regression of the early stages of atherogenesis (after 2 months of diet). The generalized character of MC disorders in LM suggests the existence of a trend towards MC reconstitution in prolonged regression in different organs and tissues. Thus, LM correction at the early stages of the pathological process can be accompanied by the disappearance of MC disorders, which seems important for the prevention of atherosclerosis.     

NADPH-diaphorase expression in the rat jejunum after intestinal ischemia/reperfusion

The purpose of this study was to analyze the nicotinamide adenine dinucleotide phosphate - diaphorase (NADPH-d) activity in the rat jejunum after a mesenteric ischemia/reperfusion injury. Nitric oxide, synthetised from L-arginine by the enzyme nitric oxide synthase, is a nonadrenergic noncholinergic relaxant neurotransmitter of the intestinal smooth muscle. It plays an important role in the process of plasticity after the ischemia/reperfusion injury. Experimental animals were divided in two groups: the control group and the ischemic/reperfusion group, with different period of the reperfusion. The NADPH-d histochemical method has been used as a marker for the nitric oxide synthase. NADPH-d activity has been rapidly decreased in the neurons of both enteric nervous systems in plexuses of the jejunum after 1 h mesenteric ischemia and 1 h reperfusion. Differences were predominantly detected in the myenteric plexus; they were seen in change of the neuronal shape, in the arrangement of neurons and in intensity of their staining. The NADPH-d positivity was absent in the intestinal crypts. After 1 h ischemia and 24 h reperfusion, the NADPH-d activity was gradually increased, but it was lower in comparison with the control group. On the 30th day following the ischemia/reperfusion there were no changes in NADPH-d positivity compared with the control animals. These results indicated that the jejunal ischemia/reperfusion has affected the neurons of the enteric nervous system of adult rats and resulted in the early decrease of NADPH-d positivity 1 h of the reperfusion insult. The gradual increasing of NADPH-d activity in 24 h following the reperfusion could be considered as a result of the plasticity process. On the 30(th) day after the ischemia/reperfusion all histochemical changes were returned to the control levels.     

Ultrastructure of blood capillaries in vascular plexuses of the lateral ventricles of the human brain

Ultrastructure of the wall of the microcirculatory bed links in the lateral ventricles of the human brain has been studied, as well as their interrelations with neural elements and ependyma. Together with typical morphological structural signs, certain peculiarities are revealed, characterizing organic specificity. Elements, performing function of the blood-brain barrier are determined: epithelium (ependyma), basal membranes, interstitium. A well developed afferent and efferent nervous apparatus of the vascular plexus, evidently, actively participates in regulation of the microcirculatory blood bed and in formation of liquor.     

Morphologic changes in the microcirculatory bed at stages of prolonged experimental fasting in animals

In 40 white male rats with body mass 180-200 g, by means of silver nitrate impregnation, morphological changes have been studied in the blood microcirculatory bed of the small intestine mesentery, spinal trapezoid muscle and eye ball conjunctiva at various stages of a prolonged fasting. With an increasing time of the experiment, a gradual undirected character of the changes in the microvessels is noted. After 3 days of fasting the changes in diameters of the microvessels, comparing to the control ones, have not any significant values in all the organs studied. After 6 days of fasting significant changes in diameters in all the links of the microcirculatory bed of the eye ball conjunctiva and in that of the spinal trapezoid muscle are observed. The microvascular changes are mostly pronounced on the 9th day of fasting. The maximal decrease of the microvessel diameters is noted in the eye ball conjunctiva, and the minimal--in the small intestine mesentery. The changes in the spinal trapezoid muscle are of intermediate character. The highest points of the structural lability gradient fall on the capillary and postcapillary-venular links of the blood microcirculatory bed.     

Effects of thermal factors on the state of microcirculation of the small intestine in acute ischemia

The influence of normo- (38 degrees C), hyper- (42 degrees C) and hypothermia (20 degrees C) on microcirculatory disturbances caused by acute local ischemia of the small intestine was investigated with the help of biomicroscopy as well as morphological methods. Ischemia was modeled by ligation of the intestine look eventrated through the abdominal wall incision of a rat onto the microscope stage for 1 h. It was shown that hyperthermia intensified microcirculatory disorders and stimulated destructive processes in tissues and hypothermia promoting microcirculation and decreasing metabolism and restrained the development of these processes. Important peculiarity of the microvascular response to ischemia, hyper- and hypothermia was revealed: heterogeneity of the reaction of different parts of microvascular bed. Appropriate evaluation of the microcirculation state in such conditions can be obtained taking into account not only the qualitative character of microvascular reaction but also an extent of this reaction manifestation in different parts of microvascular bed.     

Gender differences in ischemia-reperfusion-induced microcirculatory and epithelial dysfunctions in the small intestine

Female sex hormones have been reported to preserve endothelial integrity and to reduce inflammation. However, gender-related differences in the intestinal mucosal barrier function during compromised perfusion after ischemia and transplantation have not been defined. Herein, we applied intravital microscopy to determine the mucosal epithelial and intestinal microcirculatory responses in ileal villus and longitudinal muscle layers in a murine model of 30-min intestinal ischemia and 90-min reperfusion. In male animals, the entire reperfusion period was characterized by a significantly increased epithelial permeability. This was associated with an early leukocytic inflammatory response and late alterations in functional capillary density, capillary red blood cell velocity and mitochondrial redox state. In contrast, the female intestine exhibited a delayed increase in epithelial permeability during postischemic reperfusion. This was associated with a late leukocytic inflammatory response which did not affect the microcirculatory function. Nonetheless, at the end of the 90-min reperfusion period, the neutrophilic infiltration and structural mucosal disintegration in the female intestine were found to be pronounced to a similar extent as in the male intestine. These results suggest that in small intestinal ischemia-reperfusion the leukocytic inflammatory response and microcirculatory dysfunction develop more rapidly and are initially more pronounced in males, but the hormonal status in females is not capable of preventing the final manifestations of reperfusion injury.     

Structural changes in the pulmonary vessels and parenchyma in experimental hypercholesterolemia and atherosclerosis

Light and electron microscopy were employed to study the microcirculatory bed (MCB), intraorganic vessels and lung tissue in rabbits in the first hours (1, 3, 6, 15, 24 and 48 h) after a single administration of cholesterol (ChS) and in the course of the development of experimental atherosclerosis. The MCB demonstrated changes such as dilatation of the venular part, arteriolar constriction, red cell aggregation in capillaries and venules, and stases. At the early stages of experimental atherosclerosis induced by the diet the permeability of the air-blood barrier and the synthesis of lung surfactant were found to be deranged. Vessel-tissue changes in the lungs progressed with an increase in the length of the diet (1-8 months) and were alike the picture seen in chronic nonspecific lung diseases, particularly in what is called senile emphysema. A relationship was established between the degree of changes in the MCB and HCh gravity. Atherosclerotic lesions in the intraorganic arteries occur and progress parallel with the development of this process in the intramural arteries of the myocardium. The data obtained attest to an important role of lipid metabolism disorders in the development of lung pathology and may have a certain significance in specifying the pathogenesis of chronic nonspecific lung diseases, especially.     

Specific localization of gap junction protein, connexin45, in the deep muscular plexus of dog and rat small intestine

Cellular networks of pacemaker activity in intestinal movements are still a matter of debate. Because gap-junctional intercellular communication in the intestinal wall may provide important clues for understanding regulatory mechanisms of intestinal movements, we have attempted to clarify the distribution patterns of three types of gap junction proteins. Using antibodies for connexin40, connexin43, connexin45, smooth muscle actin, and vimentin, immunocytochemical observations were made with the confocal laser scanning microscope on cryosections of fresh-frozen small intestine and colon of the dog and rat. Connexin 45 was localized along the deep muscular plexus of the small intestine in both dog and rat. Double labeling studies revealed that connexin45 overlapped with vimentin –, but not actin-positive areas, indicating the fibroblast-like nature of the cells, rather than their being smooth muscle-like. Connexin43 immunoreactivity appeared along the smooth muscle cell surface in the outer circular layer of the small intestine of both animals. Connexin 40 immunoreactivity was not observed in the muscle layer other than in the wall of large blood vessels. It is suggested that connexin45-expressing cells along the deep muscular plexus of dog and rat small intestine are likely to act as a constituent of a pacemaker system, which may include a conductive system, by forming a cellular network operating via specific types of gap junctions.     

Histoarchitectonics and capillary-glio-neurocytic relationships in the stellate ganglion of cats

By means of injection into the microcirculatory network, section staining with hallocyanine chromic alumen, hematoxylin--eosin, silver impregnation after Bielschowsky--Gross, Baginsky, unequal intensity of microvascularization in cervical and thoracic portions have been stated, as well as different forms of interrelations between capillaries, neurocytes and gliocytes (capillaries are predominantly situated in parallel fashion to the surface of neurocytes, or else surround them). The distance between the capillary and neurocyte does not usually exceed 5--10 mkm. The contact area between neurocytes and capillaries increases with enlargement of neurocyte area. Glial and connective tissue elements are clearly differentiated after staining with acridine orange.     

The dynamics of morphofunctional changes in the microcirculation of the pelvic extremity after modeling the chief stages of its replantation]

Under study was the effect of autotransplantation in its "pure form" upon the morpho-functional reconstruction and structural mechanisms of adaptation of the blood and lymphatic links of the microcirculatory bed of extremities during early postoperation period up to 10 days. The pathophysiological state of the extremity sufficiently close to its autotransplantation was obtained by means of circular transection of soft tissues of the medial third of the femur together with the nerves and deep collecting lymphatic vessels. It was found that after modeling the main stages of replantation in the fascia and periosteum of the operated extremity there developed a spasm of the arteriolar link and dilatation of the venular and lymphatic links of the microcirculatory bed. The areas of leukocytic infiltration with the phenomena of diapedesis and microhemorrhages were revealed along the course of postcapillaries and venules in the paravasal connective tissue. The amount of functioning arteriole-venular anastomoses was increased. Against the background of pronounced oedema of soft tissues of the operated extremity the venous pressure increased and the rate of the capillary bloodflow in the skin and muscles decreased. The above changes tend to be reduced by the 10th day after modelling the main stages of replantation of the extremity.     

Morphologic indices of the rat heart after colchicine application to the vagus nerve

By means of the light optic and electron microscopic methods atrial ganglia, myocytes, vessels of the right cardiac chambers have been studied in rats 2 days--3 weeks after application of 100 mcg of colchicine on the right nervus vagus. Certain changes of the neural fibers have been described at the area of the application. In the myocardium the microcirculatory bed, focal edema and hypoxic alterations of the myocyte ultrastructure have been revealed. In the ventrical ganglia destruction of some terminals of the preganglionar fibers, chromatolysis and vacuolization of single neurocytes, as well as intraganglionar granule-containing cells have been found. The changes described take place for 7 days and they nearly completely disappear in 10 days. A suggestion is made that some phenomena, in particular, destruction of the preganglionar fibers and changes of the cardiac microcirculatory bed are connected with certain disturbances of the quick transport of substances in the nervus vagus fibers.     

Depressed neuronal growth associated protein (GAP)-43 expression in the small intestines of mice experimentally infected with Neodiplostomum seoulense

Neodiplostomum seoulense (Digenea: Neodiplostomidae) is an intestinal trematode that can cause severe mucosal pathology in the small intestines of mice and even mortality of the infected mice within 28 days after infection. We observed neuronal growth associated protein-43 (GAP-43) expression in the myenteric plexus of the small intestinal wall of N. seoulense-infected mice until day 35 post-infection (PI). BALB/c mice were infected with 200 or 500 N. seoulense metacercariae isolated from naturally infected snakes and were killed every 7 days for immunohistochemical demonstration of GAP-43 in the small intestines. N. seoulense-infected mice showed remarkable dilatation of intestinal loops compared with control mice through days 7-28 PI. Conversely, GAP-43 expression in the mucosal myenteric plexus was markedly (P<0.05) reduced in the small intestines of N. seoulense-infected mice during days 7-28 PI and was slightly normalized at day 35 PI. From this study, it is evident that neuronal damage occurs in the intestinal mucosa of N. seoulense-infected mice. However, the correlation between intestinal pathology, including the loop dilatation, and depressed GAP-43 expression remains to be elucidated.