Eksperimentalna meditsina i morfologiia最新文献

The experiments were carried out on 104 male white rats and the effects of pyracetamat, aniracetamat and 2 newly synthesized pirolidine derivatives P-CL, P-p as well as of cytidin-diphosphat choline (cyticholine) were examined on training in a water maze. All investigated substances were administered immediately after morning training orally in a dose of 100 mg/kg for a period of 5 days. Ten trainings were undertaken each day twice. Two parameters were determined: time of stay of the rat in the water maze (in seconds) and the number of mistakes (entrance of blind canals). Pyracetamat and cyticholine improved training of rats while the other examined substances showed insignificant effect. A conclusion is made that chemically close nootropic drugs could be differentiated substantially in respect to spatial memory as well.

A morphological study on experimental model of lead (Pb) neuropathy (by the method of Pentschev, A., 1966) was described. Dense inclusions in Schwann's cells and satellite cells of the sensory ganglia were found by an electron microscope in the examined peripheral nerves (n. ischiadicus) and sensory ganglia (g. lumbale and g. trigeminale--Gasseri). These finding supported direct toxic action of Pb on these structures and proved their participation in the pathogenesis of developing neuropathy.

The biological activity of the compound Iz35, representing rigid conformer of triquinol in respect to the cardiovascular system and smooth musculature, was studied. The arterial blood pressure and heart frequency were recorded in cats and rabbits as well as the tonus of smooth musculature of bronchial tree, uterus and intestines in experiments in vivo and in vitro of rats, guinea pigs and rabbits. It was established that the compound Iz35, administered in a wide range of doses of 0.1-5 mg/kg intravenously lowered systolic arterial blood pressure, but did not change chronotropic function of the heart (statistically significantly) in contrast to isoprenaline and thymolol. The compound Iz35 and trinquinol, administered intravenously in doses off 0.01-0.1 mg/kg, manifested broncholytic effect in experiments in vivo on various models of experimental bronchospasm of guinea pigs. They had still marked spasmolytic activity (1 x 10(-9)-1 x 10(-6) g/cm2 in respect to stomach-intestinal and uterine smooth musculature. The effects of Iz35 on the cardiovascular system and smooth musculature were inhibited considerably on the background of beta-adrenergic blockade (propranolol) in comparison with triquinol. The obtained data as well as our previous studies suggest to accept that these effects of the compound Iz35 are connected mainly with affecting beta-adrenergic mediator system and it manifests double agonistic/antagonistic activity in accordance with its dose characteristic.

The toxic and antitumor properties of biocysplantinum (cis-diaminodichlo-platinum) as well as a new platinum complex with acetic acid after their single and combined usage with antocyanes were studied on healthy mice and mice with transplanted ascitic tumour of Ehrlich. There was a reduction in total toxicity of biocysplatinum after simultaneous administration with antocyanes (300 mg/kg per os). Protective effect of antocyanes was observed on leukocytopoiesis. Preservation of antitumor activity of platinum complexes was found in the tumour of Ehrlich. The obtained data indicate possibilities for usage of antocyanes as chemioprotectors during therapy with drugs, containing platinum.

Morphological characteristics of neurons in the inferior olivary complex of ground squirrels at various ages were studied by a light and electron microscope. This nuclear complex consists of three nuclei: medial accessory olivary nucleus, dorsal accessory olivary nucleus and main olivary nucleus. Its cytoarchitectonics cytoarchitecture was studied by serial sections at the coronary level, stained by kresyl-violet. Two types of olivary neurons were established by silver impregnation in accordance with dendrite ramifications. Nematosomes, special forms of granulated endoplasmic reticulum, which could be probably connected with advancement of age and the process of aging were observed by an electron microscope together with organelles and intranuclear inclusions typical for the relay neurons.

Neuropharmacological study of IST was carried out on mice and rats, using the so-called practically "blind" neuropharmacological screening of M. Nikolova and L. Daleva (1968). The investigated product IST was administered under the form of 0.1-1% of solutions prepared ex tempore with saline in doses, equivalent to 1/440-1/250 to 1/2-4 1/2-4/5 of LD50. The studies on behaviour profile of mice and rats showed that IST induced symptoms of increasing inhibition of the central nervous system (CNS) in conformity with an increase in the dosage. It was established that IST inhibited dose-dependent spontaneous and stimulated with amphetamine motor activity and orientation reaction of mice, antagonized group amphetamine toxicity and excitatory effects of amphetamine as well as of morphine on mice; potentiated hexobarbital narcosis of mice and rats; lowered body temperature of rats; elevated the threshold of pentetrazolic seizures. In very high doses (50, 100 and 200 mg/kg i.p.), equivalent to 1/5 to 2/3 of LD50 IST induced excitatory effects on central and peripheral nervous system-provoked unaddressed aggressiveness, salivation, increased frequent breathing and chromodacryorrhea [correction of chromodacriurea]. The obtained experimental results show that IST manifest central depressive effect and has mainly neuroleptic character in respect to CNS.

The delipidized saline extract of Arum maculatum (AM) contains two selectively agglutinating human spermatozoa isolectinesphytospermoagglutinins (FSA1 and FSA2), which bind to various receptors of spermatozoon plasmalemma. It is established by means of disc polyacrilamide electrophoresis amino acid analysis and isoelectric focusing that FSA1 is tetrameter, but FSA2-octameter, which have similar amino-acid content and do not contain carbohydrates. The established structural differences probably cause also the capability of FSA1 and FSA2 to bind various receptors of spermatozoon plasmalemma. It is proven that FSA2 possesses antigenic properties.

A method for determination of the activity of angiotensin-converting enzyme (ACE) in the hypothalamus and hypophysis of the rat was provided. Membrane-bound enzyme was extracted from tissues by twice homogenization and centrifugation after solubilization of membrane structures with the detergent triton X-100. Protein concentrations of tissue extracts and time of incubation, at which there was linear generation of dipeptid his-lev in the course of the enzymic reaction as at the same time its degradation from tissue peptidases was under 10%, were between 0.16 and 0.35 mg/ml for the hypothalamus and between 0.07 and 0.18 mg/ml for the hypophysis with duration of incubation between 15 and 30 min. Under these conditions the enzymic activity was determined by a substrate-fal-his-lev, amounting to 18.22%-1.3 and 96.22-42 nmol/min/mg of protein (x-SEM) for the hypothalamus (n = 18) and hypophysis (n = 30) respectively. The coefficients of variation of the enzymic analysis were determined for a series in a day (1.37%) and for a series in time (9.59%). Hydrolyzing activity synonymously identified as ACE was differentiated from other tissue peptidildipeptide hydrolases by the following three criteria: hydrolyzing activity in respect to the specific for ACE artificial substrates; activation of enzymic action by Cl-; inhibition of the activity by converting inhibitors captopryl and MK 422 as well as by the helatic agent EDTA-Na2.

The morphological characteristics of the elements of the neuropile in the lower olivary complex in ground squirrels at various age were studied by an electron microscope. The peculiarities in the ultrastructure of dendrite profiles, synaptic contacts on their surface and in the content of the complex synaptic connections and glomeruli. In this nuclear complex of ground squirrels--under the conditions of hibernation as well as in old very obese ground squirrels during all seasons there were a series of changes in the ultrastructure of dendrites such as: myelin-like figures, a large number of vacuoles, an accumulation of elderly pigment at the base of proximal dendrites and free postsynaptic-like condensations C. The changes in the dendrites, which occur during various functional states as well during aging, are discussed on the basis of the analysis on ultrastructural peculiarities of elements of the neuropile in the lower olivary complex in ground squirrels at various age.

The experimental studies on cochlear prosthesis, performed at the II Moscow's medical Institute since 1981, are described. Electrophysiological and morphological results from the trial of an original electronic prosthesis, which transduces sound into electric oscillations, are presented. Data are given on morphological studies, referring to the influence of cochlear implants on the basal curve of the cochlea, to the internal structures of the cochlea and of the acoustic zone in the cortex of the large hemispheres. The results from the performed experiments show the efficiency of the described method for cochlear prosthesis and the possibility for its usage in the clinical practice.