Central and peripheral actions of delta sleep-inducing peptide on electrical stability of the heart

In rabbits under nembutal anesthesia delta sleep-inducing peptide injected intravenously or directly into a ventricle of the brain raised the threshold for ventricular fibrillation. Its effect on the electrical stability of the heart after central administration developed later than after systemic administration. Bilateral vagotomy did not alter the central effects of this peptide. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 566–568, June, 1994 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences     

Ion transport and its adrenergic regulation in erythrocyte membranes of the breamabramis brama injected with a mixture of polychlorinated biphenyls

In the first 10 days after the injection of Sovol-54 (a mixture of chlorinated biphenyls) into the breamAbramis brama, considerable alterations in the hormonal regulation of cotranport were observed for erythrocytes of this fish, along with an increase in the passive permeability of their membranes. No significant changes were recorded in Na⁺, K⁺-ATPase activity or its adrenergic regulation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 379–381, October, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Delta sleep-inducing peptide and flunitrazepam acting jointly increase cardiac electrical stability

In experiments on rabbits under Nembutal anesthesia, intravenous injection of flunitrazepam in a single dose of 0.125 mg/kg in combination with delta sleep-inducing peptide in a single dose of 60 nmol/kg raised the threshold of ventricular fibrillation to a level that was significantly higher than that after injection of flunitrazepam alone in the same dose and comparable to that after injection of this benzodiazepine alone in twice as high a dose (0.25 mg/kg), but without the side effects (persistent hypotension and transient bradycardia) produced by the latter dose. It is concluded that the ability of jointly acting delta sleep-inducing peptide and flunitrazepam to increase the electrical stability of the heart may have practical relevance to the prevention of ventricular arrhythmias occurring under conditions of emotional stress and myocardial ischemia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 342–345, April, 1995 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences     

Effect of the hypothalamic cardioactive protein-hormonal complex on choline sensitivity of the small intestine and contraction of the vas deferens in rats

A cardioactive protein-hormonal complex capable of increasing the sensitivity of the small intestine to acetylcholine about 2.5 times was isolated from magnocellular nuclei of the hypothalamo-neurohypophyseal system. Moreover, this complex enhanced contraction of the vas deferens caused by transmural stimulation, exogenous noradrenalin, and phenylephrine. The findings indicate release of transmitters from cholinergic and adrenergic neurons under the influence of the complex. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 280–282, March, 1995     

Structural and functional organization of the pain sensitivity component of lingual mechanoreceptor structures

Examination of the structural and functional organization of tactile receptor structures in the rat tongue shows that the filiform mechanosensory papillae occupying the anterior free surface of the tongue are innervated by adrenergic, cholinergic, and peptidergic fibers. The location and sources of histamine are identified. All these components are thought to be involved in organizing the pain sensitivity of mechanosensory lingual formations. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 357–361, October, 1995 Presented by A. D. Ado. Member of the Russian Academy of Medical Sciences     

Influence of general anesthesia on acute experimental poisoning of cats with the organophosphorus pesticide Anthio

It is shown that general anesthesia strongly influences the resistance of animals to poisoning with organophosphorus compounds (OPC) such as Anthio, weakens compensatory/adaptive responses, and possibly acts synergistically with OPC in impairing tissue respiration. One to three days after peroral administration of Anthio, reduced oxygen tension in arterial blood and increased heart and respiratory rates were recorded in cats, although the arterial blood pressure tended to drop markedly. Anthio poisoning led to profound changes in the autonomic regulation of functions, which was manifested in sharply decreased parasympathetic influences. The function of the brain's GABA-ergic system did not change appreciably. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 587–590, June 1994 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Mechanism of protective effect of dalargin against ischemic arrhythmias

Acute tests on cats with altered sympathetic innervation of the heart show that the protective action exerted by dalargin against the development of ischemic ventricular fibrillation is due to a modulating influence of this leu-enkephalin analog on both the sympathetic and parasympathetic regulation of cardiac activity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 8, pp. 176–178, August, 1996     

Effects of age and ischemia on levels of lipoperoxides and lipid-soluble antioxidants in the human heart

Levels of lipoperoxides and hydrophobic scavengers of free radicals were estimated in n-hexane extracts of myocardial biopsy specimens taken from cardiac patients (children and adults) during surgical operations. Ultraviolet spectra of these extracts were found to contain four absorption bands with peaks at 214, 233, 258, and 298 nm that characterize the levels of diene and triene conjugates. A comparison of the data obtained for children and adults suggested that the total antiradical activity of the cardiac muscle decreases while its content of vitamin E remains virtually unchanged during ontogeny. Significantly reduced vitamin E levels were noted in specimens from patients with chronic ischemic heart disease. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 584–586, June, 1995.     

Lipid peroxidation parameters in the internal organs of rats with different degrees of resistance to hypoxia

Lipid peroxidation and the antioxidant system of the heart, liver, and brain are studied in adult male Wistar rats with high and low resistance to hypoxia tested by “raising” to an altitude of 11.5 km and in intact outbred rats. These parameters are found to be the same in the brain of low- and high-resistance rats, while the brain content of lipid peroxidation products is higher in both groups of Wistar rats compared with outbred rats. The heart and liver parameters are coupled to the resistance to hypoxia. Antioxidant activity prevails over lipid peroxidation in the hearts and livers of high-resistance rats, confirming that oxidation plays a major role in the damaging and lethal effects of acute hypoxia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp 26–29, January, 1996 Presented by A. I. Archakov, Member of the Russian Academy of Medical Sciences     

Effect of adaptation to moderate physical loads on the increased resistance of the isolated heart to ischemia and reperfusion

Adaptation to physical loads elicits pronounced anti-ischemic and antireperfusion effects on the isolated heart. By the 20th min of total ischemia contracture in the hearts of adapted animals is much less than that in the control group. During reperfusion of hearts from adapted animals the degree of restoration of the contractile force was 6-fold higher, contracture was lesser, and the total period of tachycardia and fibrillation were 3-fold shorter than in the control. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 25–27, January, 1995 Presented by S. S. Debov, Member of the Russian Academy of Medical Sciences     

Effect of perfluorodecalin on picrotoxin toxicity and some detoxication systems

Preliminary administration (at least 7 days before the experiment) of perfluorodecalin boosts resistance to the toxic action of picrotoxin in rodents. The antidotal activity of diazepam rises under these conditions. Perfluorodecalin induces the activation of monooxygenase, conjugation, and antioxidant detoxication systems; the protein content increases in the blood serum and carboxylesterase activity is enchanged. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2. pp. 176–178, February, 1995     

Alterations in cardiac function in response to epinephrine in rats with hereditary hypertension (An ECG study)

A comparative electrocardiographic evaluation of changes in cardiac function in rats with hereditary arterial hypertension (NISAG strain) and normotensive (Wistar) rats in response to a single epinephrine injection revealed much more pronounced changes in NISAG rats, including an unfavorable time course of electrocardiographic waves (left ventricle overload) and impaired conduction (blockade) and excitability (extrasystoles). The results indicate that the myocardium of NISAG rats is much more responsive to the acute stimulation of adrenergic receptors by epinephrine than is the myocardium of normotensive rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 372–375, October, 1995 Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences     

Comparison of lipid peroxidation parameters in the heart,liver, and brain of rats with different degrees of resistance to hypoxia

The relationship between the intensity of lipid peroxidation and the activity of the antioxidant system in the heart, liver, and brain is studied in male Wistar rats with low and high resistance to hypoxia tested by being “raised” to an altitude of 11.5 km and in intact outbred rats. It is found that in all groups of rats the content of lipid peroxidation products is highest in the liver, lower in the heart, and lowest in the brain. In all groups, the rate of the ascorbate-induced lipid peroxidation is highest in the brain, lower in the liver, and lowest in the heart. The activity of the antioxidant system is highest in the brain, lower in the liver, and lowest in the heart of low-resistance and outbred rats, while in high-resistance rats it is the same in all the organs. Thus, the difference in the parameters of lipid peroxidation and, particularly, of the antioxidant system in the studied organs is most pronounced in rats with a low resistance to hypoxia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 138–143, February, 1996 Presented by A. I. Archakov, Member of the Russian Academy of Medical Sciences     

Effects of an organophosphorus compound on pulmonary and systemic circulations

Shortly (30–90 min) after an intragastric administration of the organophosphorus pesticide Anthio to cats, their cardiac output begins to decrease and the right ventricular output decreased to a greater extent than the left. Blood is redistributed to the greater circulation with a diminution of blood flow in the pulmonary lobar vessels. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 18–21, January, 1994     

Polyploidy in the myocardium and compensatory reserve of the heart

The mammalian heart is a polyploid organ. Cardiac myocytes undergo polyploidization in the early postnatal ontogeny, and the degree of their polyploid depends on the conditions of heart growth. The myocardium of healthy persons is characterized by considerable individual variability of polyploidy. The principal mechanism by which normal and compensatory growth of the heart occurs in adult mammals is through increases of cytoplasmic mass in postmitotic myocytes. In the normal myocardium, the protein mass of myocytes does not correspond to the gene dosage, while their protein mass in a hypertrophic myocardium becomes a multiple of their ploidy. The capacity of polyploid myocytes to grow so as to double their mass constitutes the reserve of cardiac growth. This reserve, which is laid down in the early ontogeny, materializes in response to functional overloading of the heart in adult life. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 454–459, May, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Seasonal differences in the development of heightened resistance of the isolated heart during adaptation to physical exercise

Substantial seasonal differences are found in the development of the cardioprotective effect of adaptation to physical exercise: in winter such adaptation results in an increase of the resistance of the isolated heart to the contracture and arrhythmogenic effects of ischemia and reperfusion, while in summer the anticontracture effect is absent and the antiarrythmic effect is significantly lowered. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 299–301, September, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Reproduction of the primary rhythms of excitation in cardiac activity of neonatal rat pups

It is shown that during activation of the central N-cholinergic systems, the cardiac pacemaker elements in neonatal rat pups are capable of switching between discontinuous rhythmic activity and the generation of periodic excitation, when complexes of cardiac contractions at a rate of 60 min⁻¹ alternate with 5–15-sec intervals of rest. This type of activity is close to the primary rhythms of excitation, which are characteristic of the activity of excitatory structures during the early phylo- and ontogenetic stages of development. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 4, pp. 422–424, April, 1994     

Responses of the arterial and venous vessels of the skeletal muscle to norepinephrine following damage to their endothelium

The functional activity of vascular endothelium in a muscle preparation from the feline gastrocnemius is impaired with ethanol, which results in an increase of an adrenergic responsiveness of the arterial compartment of the vascular bed. The exchange function of the microvessels changes little. Veins exhibit nonuniform changes in their responsiveness after exposure of their endotheliocytes to ethanol. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 315–318, September, 1994     

Correction of electrical instability of the heart with opiate receptor ligands

Peripheral injections of the μ-opiate receptor agonist DALDA,k-opiate receptor agonist spiradoline, and δ-opiate receptor blocker DuP734 significantly increased the ventricular fibrillation threshold in animals with modeled postinfarction cardiosclerosis or stress-induced damage to the heart. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 10, pp. 399–401, October, 1998     

Specific features of epithelium-dependent contractile reactions of smooth muscles in various subdivisions of the respiratory tract

Characteristic features of the endothelium-dependent smooth muscle contractile reactions to various physiologically active substances modulating adrenergic, cholinergic, and histaminergic regulatory systems are studied in rabbit trachea and in secondary and tertiary bronchi. The mechanical tension of the segments was recorded under quasi-isometric conditions. The epithelium was shown to participate in adrenergic regulation of the smooth muscles of the lower subdivisions of the respiratory tract and in the cholinergic regulation of its upper subdivisions. The histaminergic reactions of the smooth muscles in the airways had large amplitude at all levels, but the relaxing contribution of their epithelium was not detected. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 12, pp. 618–620, December, 1998