Experimental modeling of preclinical and clinical stages of Parkinson's disease.

Degeneration of dopaminergic (DAergic) neurons of the nigrostriatal system is the key stage in the pathogenesis of Parkinson's disease. The first symptoms of this disease are observed after degeneration of 70-80% neurons, which occurs over 20-30 years. The clinical stage of Parkinson's disease begins after this period.

[Optimization of counting process of dopaminergic neurons in substantia nigra of parkinsonian mice].

Parkinson's disease (PD) results from degeneration of dopaminergic (DA-ergic) neurons of sunstantia nigra pars compacta (SNc). In experimental studies, this condition is modelled by administration of neurotoxin's precursor 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP). The followed degeneration of DA-ergic neurons is estimated by cell counting.

[Compensatory reaction during degeneration of arcuate nucleus dopaminergic neurons in rats].

The study has been carried out to verify the authors' hypothesis that degeneration of dopaminergic (DA-ergic) neurons of the hypothalamic tuberoinfundibular system and concomitant development of hyperprolactinemia are accompanied by involvement of compensatory synthesis of dopamine (DA) by non-dopaminergic neurons expressing single complementary enzymes of synthesis of this neurotransmitter. Degeneration of DA-ergic neurons was produced by a stereotaxic injection into the brain lateral ventricles of 6-hydroxydopamine (6-OHDA) - a specific neurotoxin of DA-ergic neurons. 14 and 45 days after the toxin administration there were determined concentration of prolactine in peripheral blood by methods of immunoenzyme and radioimmunological analyses as well as the DA amount in the arcuate nucleus by the method of highly efficient liquid chromatography with electrochemical detection.

[Migration and differentiation of neurons producing gonadotropin-releasing hormone under conditions of serotonin excess in the brain of mouse embryos].

The work has been carried out on mice of the Tg8 line with knockout of gene of monoamineoxidase A with an increase of serotonin and noradrenaline content in the brain, and on mice of the C3H line with unchanged genome and normal concentration of monoamines. An immunocytochemical study has been performed of development of neurons producing gonadotropin-releasing hormone (GnRH) under conditions of excess of serotonin and noradrenaline in the mice in embryogenesis. The GnRH-neurons were revealed at the 18th day of embryonic development in telencephalon along trajectory of their migration from olfactory bulbs to the retrochiasmatic area.

Pregnancy-induced de-differentiation of media smooth muscle cells in uteroplacental arteries of the guinea pig is reversible after delivery.

The majority media of smooth muscle cells of uteroplacental arteries of the guinea pig is not destroyed during trophoblast invasion. Rather, most of these cells de-differentiate during pregnancy-induced arterial dilatation, forming a population of mesenchyme-like myoblasts ready to reconstitute the media after birth. We have studied the re-differentiation of these cells after delivery by means of transmission electron microscopy and immunohistochemistry using antibodies against a panel of cytoskeletal proteins.

The human placenta is encircled by a ring of smooth muscle cells.

The marginal zone of the human term placenta was studied by transmission electron microscopy and immunohistochemistry using antibodies against cytoskeletal filaments, extracellular matrix molecules and endothelial markers. The marginal sinus of the intervillous space is separated from the chorionic and basal plates by a layer of cells expressing vimentin, desmin, alpha- and gamma-smooth muscle actins, and smooth muscle myosin. Also ultrastructurally, these cells share all features with smooth muscle cells.

Stromal differentiation and architecture of the human umbilical cord.

In order to assess the characteristics of its stromal cells and the distribution of extracellular matrix proteins, we investigated, immunohistochemically and ultrastructurally, term, first and second trimester human umbilical cords. A differential distribution pattern of the various cytoskeletal proteins of stromal cells and extracellular matrix proteins was observed in different zones of the stroma, the subamniotic stroma, Wharton's jelly, and the vessels' adventitia. All three zones showed immunoreactivities for collagen types I, III and VI and for basement membrane molecules such as collagen type IV, laminin and heparan sulphate proteoglycan.

Physiological dilation of uteroplacental arteries in the guinea pig depends on nitric oxide synthase activity of extravillous trophoblast.

The trophoblast invasion of uteroplacental arteries in the guinea pig has been studied by means of electron microscopy and immunohistochemisty. To identify trophoblast cells, smooth muscle cells, and endothelial cells, antibodies against cytokeratins, smooth muscle myosin, desmin, and vimentin were employed. Furthermore, the immunohistochemical expression patterns of nitric oxide synthase isoforms (eNOS, mNOS and bNOS) were studied and were compared with the enzyme histochemical staining for NADPH-diaphorase.

Immunohistochemical localization of extracellular matrix in perivillous fibrinoid of normal human term placenta.

The extracellular matrix of perivillous fibrinoid in normal human term placenta was investigated by means of the indirect immunofluorescent technique. Polyclonal antibodies to collagen types I, III, IV, V, fibronectin, fibrinogen, laminin, entactin and heparan sulphate proteoglycan and monoclonal antibodies BC-1, IST-9 and IST-4 to human fibronectin were used. The antigens can be grouped according to their presence in fibrinoid as abundant (fibrinogen, fibronectin, heparan sulphate proteoglycan, basement membrane collagen types IV and V), absent (laminin) and variable between fibrinoids (interstitial collagen types I and III, entactin).

A kinase-related protein stabilizes unphosphorylated smooth muscle myosin minifilaments in the presence of ATP.

An apparent paradox in smooth muscle biology is the ability of unphosphorylated myosin to maintain a filamentous structure in the presence of ATP in vivo, whereas unphosphorylated myosin filaments are depolymerized in vitro in the presence of ATP. This suggests that additional uncharacterized factors are required for the stabilization of myosin filaments in the presence of ATP. We report here that an abundant smooth muscle protein forms sedimentable complexes with unphosphorylated smooth muscle myosin, partially reverses the depolymerizing effect of ATP on unphosphorylated myosin, and promotes the assembly of minifilaments as revealed by electron microscopy.

Expression of calponin in rabbit and human aortic smooth muscle cells.

Polyclonal antibodies to chicken gizzard calponin were used to localize calponin and determine calponin expression in rabbit and human aortic smooth muscle cells in culture. Calponin was localized on the microfilament bundles of cultured smooth muscle cells. Early in primary culture, calponin staining was accumulated preferentially in the central part of the cell body.

Immunofluorescent study of heterogeneity in smooth muscle cells of human fetal vessels using antibodies to myosin, desmin, and vimentin.

Immunofluorescence-microscopy was applied to study the distribution of desmin, vimentin, and smooth muscle myosin in smooth muscle of human fetal vessels. Serial cryostat sections of the vessels examined all reacted positively with myosin and vimentin antibodies. However, heterogeneous staining of the vessels with desmin antibodies was observed.

Confocal and conventional immunofluorescent and immunogold electron microscopic localization of collagen types III and IV in human placenta.

Confocal and conventional indirect immunofluorescence and immunogold electron microscopic methods were applied to examine the distribution of extracellular matrix constituents (collagens types III and IV) in the villi of immature and term human placentae. The immunofluorescence study revealed that collagen type III is more distinct in the villous stroma of term placenta as compared with that of the first trimester. Collagen type IV was detected mainly in endothelial and epithelial basement membranes and interestingly also to a certain extent in the stroma.

Immunohistochemical investigation of autoantibodies to nerve fibers in cardiomyopathy.

The immunofluorescence technique was used to trace auto-antibodies to neural structures in the blood serum of 180 patients with various cardiomyopathies and 20 healthy probands (controls). Incubation of cryostat slices of heart, kidney, spinal cord and medulla oblongata of Wistar-rats or of cell cultures of embryonal spinal cord with the blood serum of patients with cardiomyopathies resulted in immunofluorescence of nerve fibres and neuronal perikaryon. The controls were negative.

[Distribution of myosin, desmin and vimentin in smooth muscle cells of human embryonic vessels].

Immunofluorescent study of embryonal vessels of man using antibodies to myosin, desmin and vimentin showed heterogeneity of smooth muscle cells. It is supposed that the use of desmin as a marker of cell differentiation can increase the role of modified phenotypes in the development of the pathological process in the vascular wall.

Participation of collagen types I, III, IV, V, and fibronectin in the formation of villi fibrosis in human term placenta.

The indirect immunofluorescence method was used to study the human term placenta in pathological pregnancy for the distribution of collagen types I, III, IV, V, and fibronectin in fibrosis stromatis villi. All collagen types and fibronectin were shown to participate in fibrosis villorum formation. Fibronectin was also detected in the fibrinoid that surrounded villi at stroma.

[Distribution of collagen types III and IV in human placental villi].

Immunofluorescent examination showed more significant accumulation of interstitial collagen type III in the stroma of mature placenta compared with immature one. Localization of membrane collagen type IV was found neither in basal membranes of epithelium and villous vessels of mature term placenta, nor in their stroma. The described patterns of distribution of collagen types III and IV in human placenta villi were proved by immunoelectronmicroscopic method.

[The localization of the components of the extracellular matrix and cytoskeleton in myocardial biopsies in alcoholic cardiomyopathy].

Distribution of I, III, IV and V-type collagen, fibronectin, vimentin, filamin, and desmin in myocardial biopsy specimens of 8 patients with alcoholic cardiomyopathy was studied by indirect immunofluorescence. It is found that all types of collagen and fibronectin participate in formation of diffuse cardiosclerosis while small cardiosclerosis is formed by interstitial types of collagen and to a lower extent of fibronectin. Filamin and desmin distribution in cardiomyocytes proves deformation and destruction of Z-lines and intercalated discs.

[Epstein-Barr virus infection and congestive cardiomyopathy (serologic and immunomorphologic aspects)].

In serums of patients with congestive cardiomyopathy (CCM), patients with ischemic heart disease (IHD) and those of healthy subjects, presence of antibodies to capsid and early antigens of Epstein-Barr's virus (EBV) and to various structural components of myocardium was determined in order to study seroepidemiologic relations between the infection and CCM as well as immunopathogenic reactions against myocardium in this disease. Seroepidemiologic relation between EBV and CCM consisted in significant (compared to healthy subjects and patients with IHD) increase in average geometrical titres of antibodies to virus-associated antigens. Half of the patients with CCM had active EBV infection proved by presence of antibodies to early EBV antigen.

[Features of the extracellular matrix of fibroadenomas and leaf-shaped tumors of the human breast (immunomorphologic study)].

Fibronectin and collagen I, III, IV, V distribution in preexisting and newly formed connective tissue of fibroadenomas and leaf-like human breast tumour was studied by the immunofluorescent method. Extracellular matrix of a newly formed connective tissue was characterized by the predominance of collagen type III, the presence of collagen type IV, a high content of fibronectin in a leaf-like tumour. Such characteristics of the extracellular matrix structure in benign tumours are interpreted as a manifestation of desmoplasia.

[Plasmorrhagia into the myocardial cells after adrenaline-induced myocardial damage].

The immunomorphological and electron microscopy methods were used to study the myocardial damage in mice induced by adrenaline injections. The dynamics of plasmorrhagia was characterized by initial deposition of fibrinogen-fibrin mainly in the area of the sarcolemma of the myocardial cells followed by diffusion into the muscular fibres.