Role of the peripheral catecholaminergic systems in the antistress action of neuropeptides

The mediator activity of the peripheral catecholaminergic systems (the adrenergic nerves of dura mater and the concentrations of noradrenaline and adrenaline in the adrenals of rats) during dynamic and immobilization stress was investigated with the help of fluorescent microscopy and spectrofluorometry. Neuropeptides--dalargin and another enkephalin analog--were injected intraperitoneally, 150 mg/kg. A visible antistress action of these neuropeptides has been demonstrated, it was more marked after treatment with dalargin. The role of peripheral catecholaminergic system in the mechanism of stress-protective effects of neuropeptides is discussed.     

Relation of the ultrastructural organization of mouse mammary gland cancer to its ability to metastasize]

A quantitative ultrastructural investigation of cancer in mice mammary glands and of its metastases to the lungs was carried out. It was established that in tumors showing no metastatic spreading in experiment the area of membrane surface of the endoplasmic reticulum and the number of bound ribosomes are greater than those in tumor spreading metastases. At the same time the number of ribosomes organized into polysomes is higher in the metastasized tumors. The comparison of the tumors with their metastases revealed differences in the structure of the mitochondrial apparatus: the surface area of cristae is larger in the metastatic foci. The evidence obtained shows that tumors spreading metastases have a lower level of cellular differentiation. The primary and metastatic foci do not exhibit any difference in the level of differentiation.     

The lymphocyte acetylcholinesterase activity in rats poisoned by pesticides

The experiments carried out present the evidence of acetylcholinesterase activity of Wistar rat lymphocytes. It was shown that splenocytes and thymocytes had significantly different levels of the enzyme activity. Peroral administration of phosphor-organic pesticide antio (phormothion) 1/100 and 1/20 LD50 induced the dose-dependent inhibition of splenocyte acetylcholine-esterase activity after 2 months of treatment. It suggests the relation of the immunosuppressive action of pesticide with the interference into the neuromediator mechanisms regulating the lymphoid cell function.     

Method of measuring the modulus of elasticity of human muscle tissue

An experimental method is described for estimating the mechanical properties of human soft tissues by calculating Young's modulus which was defined according to the slope of the hysteresis curve of the test subject, reflecting the dependence of its deformation on the force applied. The main causes of numerous difficulties in obtaining such data and the ways for their overcoming are considered. Experiments were made on the biceps in the isometric mode under different degrees of internal tension. It has been shown that the higher the physical development of the test subject the less the magnitude of Young's modulus. The dependence of its magnitude on the degree of muscular tension is sublinear in character in the group with good physical development and superlinear in that with poor physical development.     

The effect of phenobarbital and amidopyrine on the rate of decomposition of isoforms of cytochrome P-450 in mouse liver microsomes

Separation of microsomal proteins in gradient polyacrylamide gel gives 60 protein bands. The molecular mass range of 48-58 kDa corresponding to cytochrome isozymes contains 7 bands for intact mice and 8 bands for phenobarbital-induced mice. Phenobarbital treatment causes both the appearance of a new cytochrome P-450 isozyme with a molecular mass of 56 kDa and the increase in the content of three isozymes with molecular masses of 54, 52.5 and 50 kDa. The half-life time of cytochrome P-450 isozymes in the livers of intact and phenobarbital-induced mice differs from 15 to 42 hours. Phenobarbital induction results in the breakdown acceleration of the isozyme with a molecular mass of 52.5 kDa and the breakdown retardation of the isozyme with a molecular mass of 54 kDa. Aminopyrine injections to phenobarbital-pretreated mice result in the breakdown acceleration of the cytochrome P-450 isozyme with a molecular mass of 56 kDa.     

Organ-specific human prostate beta-globulin during tumor growth

An organ specific protein antigen having an electrophoretic mobility of beta-globulin was demonstrated in human prostate. Its physicochemical properties (relative electrophoretic mobility, diffusion coefficient, molecular weight and relation to different precipitating agents) were determined. The indirect immunofluorescence technique revealed that this antigen is synthesized by the glandular epithelium of the main glands. A statistically significant decrease was found in the concentration of prostatic beta-globulin in tumors of the prostate. The synthesis of this protein was shown to start only in the period of puberty.     

Preservation of differences in the degree of polymerization of actin, isolated at different stages of ontogenesis after its purification]

Actin preparation from skeletal muscles of new-born, 10 days old and adult rabbits, containing less than or equal to 5% of inactivated actin and 1-2% of other myofibrillar proteins, were studied by means of flow birefringence and viscosimetry. It is found, that, like earlier studied crude preparations, purified actin preparations, isolated at different ontogenesis stages, differ in their intrinsic viscosity and extinction angle. These differences retain after the additional trypsin treatment. Non-polymerizing fraction of Straub F-actins, isolated from rabbit muscles of all ontogenesis stages studied, practically does not affect the polymerization in the course of ontogenesis, which is due to changes in its stucture.