Characterization of cardiac function in hypertensive rats of the NISAG strain (an ECG study)

Analysis of ECGs recorded in 3 standard leads, 3 augmented limb leads, and 3 chest leads revealed typical signs of left ventricular hypertrophy with a relative deterioration of coronary blood supply in NISAG rats, a new strain with hereditary arterial hypertension. These signs are considered to be characteristic of an established arterial hypertension and may be taken as evidence that the NISAG strain can serve as an adequate animal model of human hypertensive disease. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7 pp. 17–18, July, 1994 Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences     

Phospholipase B activity in congenitally athymic (nude) mice infected withTrichinella spiralis

The effects of an infection with 200Trichinella spiralis larvae on the intestinal phospholipase B activity and bone marrow eosinophilia of congenitally athymic (nude) mice (BALB/c; NU/NU) were studied. Nude mice were used since it had been shown that they do not undergo a typical worm expulsion and also they lack a thymus. The results showed that nude mice do not develop either an increased bone marrow eosinophilia or an elevation in intestinal phospholipase B activity. The findings thus support the hypothesis that phospholipase B is involved in the expulsion of parasitic worms and that elevated enzyme levels and expulsion are thymus cell dependent.     

Dynorphin A (1-17), Met-enkephalin-Arg6-Phe7 and substance P (1-11) levels in the brain of mice with different levels of ethanol consumption

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N ^o 8, pp. 177–178, August, 1993     

Inhibition of alcohol uptake in C57BI/6 mice by splenocytes extracorporeally stimulated with vasopressin

Experiments on C57BI/6 mice kept under conditions of free choice between alcohol and water for 4 and 12 months showed that adoptive transfer of splenocytes extracorporeally stimulated with arginine vasopressin suppressed alcohol intake. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 6, pp. 617–619, June, 2000     

Endocrine functions in hypertensive rats of the NISAG strain exposed to epinephrine

Endocrine functions were investigated in normotensive (Wistar) and hypertensive (NISAG) rats before and on days 3, 7, and 21 after subcutaneous epinephrine administration. Rats of the NISAG strain are characterized by elevated plasma levels of aldosterone and thyroxine and lowered plasma levels of immunoreactive insulin, and their endocrine system develops a much stronger response to a single epinephrine injection than does that of Wistar rats. This is manifested in a still higher aldosterone level, elevated corticosterone and insulin concentrations, and reduced thyroxine content in the plasma. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 495–498, May, 1996     

Whole exon 5 and intron 5 replaced by RHCE in DVa(Hus)

The D^Va(Hus) was previously investigated through cDNA analysis, which revealed an RHD-CE(5)-D hybrid allele. However, the 5 and 3 breakpoints remain unknown. In this article, gene recombinations between the RHD and RHCE alleles were investigated by a combination approach of a sequence-specific primer PCR (PCR-SSP) and an RHD full-length coding region sequencing method on two Chinese subjects with weak D phenotypes. The hybrid Rhesus box of each individual was also investigated through an established PCR-based method. As a result, two partial D phenotypes, D^Va(Hus) and D^VI type III, were identified, each carrying one hybrid RHD-CE-D allele. The two samples were also serotyped with Rh phontypes of DccEe and DCcee, respectively. Other sequencing analyses of the D^Va(Hus) sample showed that the sequence of intron 4 is identical with RHD, whereas the whole sequence of exon 5 and intron 5 is identical with RHCE except for seven polymorphisms in the intron 5. We may concluded that in the case of this Chinese D^Va(Hus), the whole exon 5 and complete intron 5 of a total segment of 1801 nucleotides were replaced by RHCE suggesting that the breakpoints of the replaced region are the 5 end of the exon 5 and the 3 end of the intron 5.     

Selection of anxious mice by a three-stage test in an elevated T-maze

Daily testing of SHR and C57Bl/6 mice during 3 days shows an increase of the number of mice with a high level of anxiety, which was determined according to the ratio of the number of entries into the light arms to the total sum of entries into the light and dark arms of an elevated T-maze. Such results were obtained after 3 testings every 3 days in C57Bl/6 but not in SHR mice. This procedure is proposed for the selection of anxious individuals as objects for an anxiety model. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 355–356, March, 1996 Presented by S. N. Golikov, Member of the Russian Academy of Medical Sciences     

Effect of extract from a transplant for eyelid plasty (series ALLOPLANTTM) on DNA synthesis in cultures cells

Extract isolated from a collagen-containing transplant (series ALLOPLANT^TM), which is used in the treatment of benign and malignant neoplasms of the eyelid, inhibits DNA synthesis in the cellin vitro. This effect is nonspecific, reversible, and dose-dependent. The extract is thermostable and resistant to proteolytic enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 75–79, January, 1994     

Cellular mechanism of force development in cat middle cerebral artery by reducedPCO2

These studies were undertaken to determine the effect of reducing aPCO₂ below physiological levels on cat middle cerebral artery. Upon reduction ofPCO₂ from 37 to 14 torr (pH 7.4) we observed membrane depolarization and force development. ReducingPCO₂ decreased the slope of theE _m vs. log [K]_o curve and increased the slope of the steady-state I/V relationship suggesting that the change inE _m was due to reduction of outward K⁺ conductance (g _k). Elevation of pH from 7.37 to 7.6 had a very similar effect on these cerebral arterial muscle cells, depolarizing the muscle membrane (reducing theE _m vs. log [K]_o curve) and increasing the slope of the I/V relationship to statistically equivalent values as reduction ofPCO₂. ReturningPCO₂ from 14 to 37 torr rapidly relaxed these preparations, but only transiently. This relaxation was followed by a rebound contraction within 3 min, demonstrating a transient nature for the action of elevatingPCO₂ in cerebral arteries. The response to changing pH_o followed a slower time course but did not change with time. These studies demonstrate that both elevated pH_o and reducedPCO₂ activate cerebral arterial muscle by a mechanism which includes reduction ing _k. However, it can not be determined if these similar responses and reduction, ofg _k are mediated by changing pH_i or mediated through different mechanisms. It is possible that pH_o andPCO₂ can modify cerebral arterial tone by direct mechanisms and not necesarily by their effect on pH_i. It is clear, however, that reduction ofPCO₂ and elevation of pH_o both activate cerebral arterial muscle by a mechanism which includes reduction ofg _k.This study was supported by NIH grant no. HL-32871. Dr. Harder is an established investigator of the American Heart Association     

Polymorphisms within human cytomegalovirus chemokine (UL146/UL147) and cytokine receptor genes (UL144) are not predictive of sequelae in congenitally infected children

Human cytomegalovirus (HCMV) viral chemokine, UL146, and TNF alpha-like receptor UL144 genes show a high degree of hypervariability in clinical isolates. These proteins are predicted to be immune modulators and may contribute to the pathogenesis of HCMV infections. We analyzed the UL146 and UL144 genetic variation of 51 HCMV isolates from congenitally infected children and 13 isolates from children in childcare. There was no statistically significant correlation between UL146 and UL144 genotypes and HCMV disease and/or sequelae. However, there were some groups that had a relatively large proportion of asymptomatic outcomes. These included UL146 group 8 (7/8 asymptomatic) and UL146 group 10 (3/3 asymptomatic). UL144 group B had 11/15 (73%) asymptomatic. UL146 and UL144 genes remained stable in serial isolates from children in daycare for intervals up to three years. These results indicate that most UL146 and UL144 genotypes do not predict clinical sequelae following congenital HCMV infections.     

Changed count of CD4+ T-lymphocytes in the bone marrow of aggressive CBA mice

Enhanced immune response of aggressive CBA mice after 10 daily confrontations in sensory contact on day 4 after immunization with sheep red blood cells (5×10⁸) is paralleled by an increase in the count of CD4⁺ T-cells in the bone marrow. Aggressive behavior, weight of the spleen, and count of CD4⁺ T-helpers in the bone marrow (which is increased only in aggressors with a history of at least 3 victories) are correlated. The effect of aggressive behavior on immunity can be caused by changes of the neurochemical status of the brain and determined by an increase in the CD4⁺ T-helper count. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 11, pp. 544–546, November, 1997     

Contribution of tumor necrosis factor to the lethality of mice with endotoxin shock presensitized by serum from tumor-bearing mice

Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 115, No. 1, pp. 57–59, January, 1993.     

Lymphocytes from mice with a 1-methyl-4-phenyl-1,2, 3,6-tetrahydropyridine(MPTP)-induced parkinsonian syndrome reduce motor activity in C57Bl/6 mice

Motor activity of C57Bl/6 mice is found to be decreased following syngeneic transfer to them of splenocytes from mice with an MPTP-induced parkinsonian syndrome. The decrease in motor activity does not result from the transfer of MPTP and is apparently associated with the transfer of B lymphocytes and with antibody production by these cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 3, pp. 232–234, March, 1994     

Copulatory behavior of old-field mice (Peromyscus polionotus) from different natural populations

In an effort to study a biologically important behavioral pattern in different naturally occurring populations of the same species, the copulatory behavior ofPeromyscus polionotus from South Carolina and from Santa Rosa Island, Florida, was compared with that ofP. polionotus from the Ocala National Forest, Florida. Twelve male and 16 female South Carolina mice received 71 tests, and five male and three female Santa Rosa mice received 18 tests. The basic pattern was identical across all three samples, being characterized by no lock, no intravaginal thrusting, multiple intromissions, and multiple ejaculations. Prolonged intromissions followed organized ejaculatory series. Quantitative differences among samples were found for several measures. Intromission Frequency appears particularly susceptible to local variation. Between-population differences in copulatory behavior appear to be of a quantitative rather than a qualitative nature.     

Regulation of membrane excitability by intracellular pH (pHi) changers through Ca2+-activated K+ current (BK channel) in single smooth muscle cells from rabbit basilar artery

Employing microfluorometric system and patch clamp technique in rabbit basilar arterial myocytes, regulation mechanisms of vascular excitability were investigated by applying intracellular pH (pH_i) changers such as sodium acetate (SA) and NH₄Cl. Applications of caffeine produced transient phasic contractions in a reversible manner. These caffeine-induced contractions were significantly enhanced by SA and suppressed by NH₄Cl. Intracellular Ca²⁺ concentration ([Ca²⁺]_i) was monitored in a single isolated myocyte and based the ratio of fluorescence using Fura-2 AM (R _340/380). SA (20 mM) increased and NH₄Cl (20 mM) decreased R _340/380 by 0.2 ± 0.03 and 0.1 ± 0.02, respectively, in a reversible manner. Caffeine (10 mM) transiently increased R _340/380 by 0.9 ± 0.07, and the ratio increment was significantly enhanced by SA and suppressed by NH₄Cl, implying that SA and NH₄Cl may affect [Ca²⁺]_i (p < 0.05). Accordingly, we studied the effects of SA and NH₄Cl on Ca²⁺-activated K⁺ current (IK_Ca) under patch clamp technique. Caffeine produced transient outward current at holding potential (V _h) of 0 mV, caffeine induced transient outward K⁺ current, and the spontaneous transient outward currents were significantly enhanced by SA and suppressed by NH₄Cl. In addition, IK_Ca was significantly increased by acidotic condition when pH_i was lowered by altering the NH₄Cl gradient across the cell membrane. Finally, the effects of SA and NH₄Cl on the membrane excitability and basal tension were studied: Under current clamp mode, resting membrane potential (RMP) was −28 ± 2.3 mV in a single cell level and was depolarized by 13 ± 2.4 mV with 2 mM tetraethylammonium (TEA). SA hyperpolarized and NH₄Cl depolarized RMP by 10 ± 1.9 and 16 ± 4.7 mV, respectively. SA-induced hyperpolarization and relaxation of basal tension was significantly inhibited by TEA. These results suggest that SA and NH₄Cl might regulate vascular tone by altering membrane excitability through modulation of [Ca²⁺]_i and Ca²⁺-activated K channels in rabbit basilar artery.     

Effect of interferon on the development of parkinsonism induced by the administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in C57Bl/6 mice

The administration of reaferon, a recombinant α-interferon preparation, hampers the development of parkinsonism caused by MPTP administration in C57Bl/6 mice. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 503–505, May, 1996     

Effect of recombinant human erythropoietin on the rate of Na+,H+-exchange in erythrocytes from patients with chronic renal failure on hemodialysis

The study explores the effect of recombinant human erythropoietin and the rate of Na⁺,H⁺-exchange in erythrocytes from patients with chronic renal failure undergoing hemodialysis. The rate of Na⁺,H⁺-exchange in erythrocytes from patients was higher than in the control and remained unchanged after 24 months of treatment with erythropoietin. Therapy with recombinant human erythropoietin does not normalize the Na⁺,H⁺-exchange mechanism. It is concluded that factors underlying disturbances of ion transport in erythrocytes from uremic patients cannot be corrected with erythropoietin. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 12, pp. 613–615, December, 1997