Throughout the studies the following experimental results were summarized. 1. It was impossible to infect and kill the mice, weighing 10 to 12 gm, by inoculating 0.2ml of virulent Cl. chauvoei, diluted 1 to 10 with physiological saline, via subcutaneous, intramuscular, intraperitoneal or intraveonus, route. 2. The mice which were inoculated in brain with 0.03ml of Cl. chauvoei diluted 1 : 5120 with physiological saline were resulted in all death after infection, but not in case of attenuated strain even in dilution of one to five. 3. Virulent Cl. chauvoei were diluted with each of those of whole blood, erythrocytes and serum of horse, calf, swine, sheep, rabbit, guinea pig, chicken and duck, human plasma and 2% CaCl solution, and inoculated subcutaneously 0.25 to 0.5ml in mice, weighing 12 to 15gm. It was resulted in significant increase in virulence as comparing with the case of physiological saline solution except when horse and pig sera were used. Such a phenomena were not seen in attenuated strain. 4. Virulence of virulent Cl. Chauvoei could be increased significantly in rat, as the procedures used in mice, by suspending in whole blood, erythrocytes, serum, or plasma of various animals, or 2% $CaCl_2$ solution and by inoculating subcutaneously 0.5 to 10ml in rat, weighing 30 to 60 gm, as compared with those of control group which used physiological saline solutionos diluent. 5. Mice resisted 100 and 80 percent against challenge of $10^3$ and $10^4$ M.L.D.. respectively, 24 hours after inoculation of 0.5ml black leg antiserum. 6. Immune response to the black leg living vaccine in mice could be obtained more favorably in the group of respected vaccination rather than those of single inoculation and the most profitable inoculm size of the vacine was 0.5 to 1.0ml. 7. Challenge for the immunized mice could be carried out effectively 3 weeks after first vaccination. 8. Satisfactory results could be obtained by inoculating subcutaneously for the immunization and intracerebrally or subcutaneously for the challenge. 9. Mice which were inoculated with 0.5ml of black leg living vaccine via subtaneucously two times at seven days interval and 21 days after first inoculation and challenged with 5 and 10 M.L.D. of virulent strain, resited 100 and 70 to 80 percent respectively. Same results were obtainable in black leg killed vaccine as the procedures used in living vaccine. 10. There were significantly different resistances against the definite challenge does between the mice groups which were immnuized with the living vaccine diluted five or 10 times and the undiluted. 11. For the biological assay of black leg living vaccine and antiserum, satisfactory results could be obtained using mice.
The neurogenic responses of tracheal smooth muscles to electrical field stimulation (EFS) is biphasic, consisting firstly of cholinergic contraction followed by a slow and sustained relaxation. It is well known that a sustained relaxation involves the inhibitory non-adrenergic non-cholinergic systems. This study was done to Investigate the relaxing agents and their action mechanisms by use of an organ bath with plati- ilum . The tracheal smooth muscle relaxation due to EFS was suppressed by L-NAME, the WO (Nitric Oxide) synthase inhibitor, and these effects were reversed by L-arginine, the precursor of NO. Also, L-WAME (HG-nitro-L-arginine methyl ester) increased the basal tension. Nitroprusside, the NO-donor, suppressed the tracheal basal tension greatly. Methylene blue, the inhibitor of guanylate cyclase, decreased EFS-induced relaxations and increa ed basal tension. Forskolin and isoprenaline, which are activators of adenylate cyclase, suppressed tracheal basal tension in the same way as nitroprusside. TEA (tetraethylammonium), the non-specific K'channel blocker, and apamin, the Ca"-activated K'channel blocker, increased tracheal basal tension and EFS-induced relaxations. Our results indicate that Pr3 Is released upon stimulation of the NANC (Won Adrenergic Won Cholinergic) nerves in guinea-pig tracheal smooth muscle and that the release of NO related with the K+ channel, as well as the release of other inhibitory agents< e. g.)VIP (Vasoactive Intestinal Polypeptide), PHI (Peptide Histidine Isoleusine) > mediated via CAMP (cyclic Adenosine Monophosphate) may be Involved In sustained relaxation.
The Journal of the Korean Society for Microbiology
/
v.20
no.1
/
pp.65-72
/
1985
Vitamin C is known as an integral element for the formation and maintenance of intercellular supporting structures. Ascorbic acid has been used for the treatment of certain poisonings and hypovitaminosis(scurvy) but also known as a powerful reducing agent, and can kill a variety of bacteria and detoxify bacterial exotoxins including various clostridial exotoxins in vitro. For viruses, vitamin C inactivates herpes virus, vaccinia virus and influenza virus and has been used for the prevention and treatment of the common cold. Thus ascorbic acid plays an important role in antimicrobial action. Scurvy also promotes the development of tubercles in experimentally infected guinea pig and the tuberculosis patients require more vitamin C than normal persons. However there is no reports that ascorbic acid could inhibit the growh of M. tuberculosis. In this paper, antibacterial effects of ascorbic acid against M. tuberculosis were studied. The results are as follows: 1. The single use of the ascorbic acid exhibited antibacterial effect in vitro against $5{\times}10^3/ml$ of M. tuberculosis $H_{37}$ Rv at the concentration of ascorbic acid 0.625mg/ml over 3 hours exposure and 0.05mg/ml over 9 hours exposure. 2. In vivo mice administered with ascorbic acid 50mg/day for 5, 10 and 15 days respectively were protected from M. tuberculosis $2LD_{50}$, $3LD_{50}$, $4LD_{50}$ and $5LD_{50}$ given intravenously.
Journal of the Society of Cosmetic Scientists of Korea
/
v.23
no.3
/
pp.134-146
/
1997
Consumers have recently preferred to purchase extensive UV intercepting products, which are waterproof and free from side effects on skin. Testing Cytoroxicity in SR method, cell survivial ratio of UV-B interceptors decreased above 0.08W/V%, and so did that of UV-A interceptors above 0.06W/V%. Also, Patch-test of inorganic UV interceptors resulted in no skin irritation even below 10.0 and 11.25. UV interceptors in the sunlight showed yellowish discoloration in 5 to 14 days. In absorption curves, UV-B was most suitable for Octyl methoxycinnamate and UV-A for Butyl methoxy dibenzoylmethane. Fro this reason, Nylonpoly UVA/UVB the material of OMC and BMDM coated with Nylon & polyethylene, was used as the organic UV interceptor. And zinc oxide and titanium dioxide was used as inorganic UV ibterceptors. The appropriate mixture ratio of ZnO and TiO2 was 6 to 4.6% of ZnO, 4% of TiO2 and 5% of Nylonpoly UVA/UVB were all combined with our sunscreen cream. The SPF value of in-vivo applied to a guinea pig was 34.9 and that of in-vivo was 38.5. Cyclomerhicone and dimerthicone were used in water-in-Silicone system. Ceryl diverhicone and sorbitan sesquioleate were used as emulsifiers and MgSO4, 7H2O, Mg-stearate/Mg-Al-stearate copolymer as emulsification stabilizers. In practical application, each SPF duration of O/W type and W/S type containing sunscreen cream of the same content showed that W/S type of sunscreen cream was 5 times as durable as the other. This product is fit for using in swimming, climbing or skiing. This research is to minimize skin trouble used by UV interceptors and to make one with proper softness, skin safety and UV intercepting efficiency.
The peptide with structural similarity to mammalian substance P (M-SP) has been isolated from extract of the body of the African lungfish, Protopterus dolloi, using the rectum of the newt as the bioassay system. The primary structure of the SP-related peptide was identified as Lys-Pro-Arg-Pro-Asp-Gln-Phe-Tyr-Gly-Leu-Met-NH2 (L-SP) and contained four substitutions ($Lys^{1}\rightarrow $ Arg, $Arg^{3}\rightarrow$ Lys, $Asp^{5}\rightarrow$ Gln, and $Tyr^{8}\rightarrow$ Phe) compared with M-SP; this structure is identical to that of the peptide isolated from the gut of the Australian lungfish. Circular dichroism spectra showed that L-SP had an unordered structure in the buffer solution and phospholipid bilayers. This peptide was found to have an excitatory effect on rectal muscle tissues of newt, quail, and fish. L-SP also had a more potent vasodilatory effect on the guinea-pig aorta than that of M-SP. The identification of the peptide provides evidence that SP family, hitherto confined to mammals, have a widespread occurrence in lungfish.
Aravinthan, Adithan;Kim, Jong Han;Antonisamy, Paulrayer;Kang, Chang-Won;Choi, Jonghee;Kim, Nam Soo;Kim, Jong-Hoon
Journal of Ginseng Research
/
v.39
no.3
/
pp.206-212
/
2015
Background: Ginseng total saponin (GTS) contains various ginsenosides. These ginsenosides are widely used for treating cardiovascular diseases in Asian communities. The aim of this study was to study the effects of GTS on cardiac injury after global ischemia and reperfusion (I/R) in isolated guinea pig hearts. Methods: Animals were subjected to normothermic ischemia for 60 minutes, followed by 120 minutes of reperfusion. GTS significantly increased aortic flow, coronary flow, and cardiac output. Moreover, GTS significantly increased left ventricular systolic pressure and the maximal rate of contraction ($+dP/dt_{max}$) and relaxation ($-dP/dt_{max}$). In addition, GTS has been shown to ameliorate electrocardiographic changes such as the QRS complex, QT interval, and RR interval. Results: GTS significantly suppressed the biochemical parameters (i.e., lactate dehydrogenase, creatine kinase-MB fraction, and cardiac troponin I levels) and normalized the oxidative stress markers (i.e., malondialdehyde, glutathione, and nitrite). In addition, GTS also markedly inhibits the expression of interleukin-$1{\beta}$ (IL-$1{\beta}$), IL-6, and nuclear factor-${\kappa}B$, and improves the expression of IL-10 in cardiac tissue. Conclusion: These data indicate that GTS mitigates myocardial damage by modulating the biochemical and oxidative stress related to cardiac I/R injury.
In order to investigate the pharmacologic properties of New Wonbang Woohwangchungsimwon Pill(NSCH), effects of Wonbang Woohwangchungsimwon Pill (SCH) and NSCH were compared using various experimental models. In rat aorta, NSCH and SCH made the relaxation of blood vessels in maximum contractile response to phenylephrine (10-6 M) regardless to endothelium containing or denuded rings of the rat aorta. Furthermore, the presence of the inhibitors of NO synthase and guanylate cyclase did not affect significantly the relaxing effects of NSCH and SCH. NSCH and SCH inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NSCH and SCH decreased significantly heart rate. These, at high doses, had a negative inotropic effects that was a decrease of left ventricular developed pressure and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In guinea-pig papillary muscle, these had no effects on parameters of action potential such as action potential amplitude (APA), $V_{max}$ and resting membrane potential (RMP) at low doses, whereas inhibitory the cardiac contractility at high doses. Furthermore, these had a significant inhibitory effects on palpitation of the heart in normotensive rats and SHRs. These had a significant inhibitory effects on palpitation of the heart in normotensive rats and SHRs. These results suggest that NSCH and SCH have weak cardiovascular effects, and that there is no significant differences between cardiovascular effects of two preparations.
Kim, Yang-Mi;Park, Hong-Ki;Han, Jae-Hee;Park, Choon-Ok;Hong, Seong-Geun
The Korean Journal of Physiology and Pharmacology
/
v.2
no.6
/
pp.743-752
/
1998
The atrial acetylcholine-activated $K^+\;(K_{ACh})$ channel is gated by the pertussis toxin-sensitive inhibitory G $(G_K)$ protein. Earlier studies revealed that ATP alone can activate the $K_{ACh}$ channel via transphosphorylation mediated by nucleoside-diphosphate kinase (NDPK) in atrial cells of rabbit and guinea pig. This channel can be activated by various agonists and also modulated its function by phosphorylation. ATP-induced $K_{ACh}$ channel activation (AIKA) was maintained in the presence of the NDPK inhibitor, suggesting the existence of a mechanism other than NDPK-mediated process. Here we hypothesized the phosphorylation process as another mechanism underlying AIKA and was undertaken to examine what kinase is involved in atrial cells isolated from the rat heart. Single application of 1 mM ATP gradually increased the activity of $K_{ACh}$ channels and reached its maximum $40{\sim}50$ sec later following adding ATP. AIKA was not completely reduced but maintained by half even in the presence of NDPK inhibitor. Neither ADP nor a non-hydrolyzable ATP analogue, AMP-PNP can cause AIKA, while a non-specific phosphatase, alkaline phosphatase blocked completely AIKA. PKC antagonists such as sphingosine or tamoxifen, completely blocked AIKA, whereas PKC catalytic domain increased AIKA. Taken together, it is suggested that the PKC-mediated phosphorylation is partly involved in AIKA.
These experiments were carried out to clarify the optimalconditions and interspecific cross reaction of H-Y antibody activity. H-Y antiserum was prepared in inbred SD female rats and Balb/c female mice by repeated immunization of rat newborn testis homogemate, rat and mouse spleen cells obtained from males of same strain. The activity of H-Y antibody in antiserum was tested by ELISA and biological tests. The cross reactivity of H-Y antibody was confirmed by culturing mouse and rabbit embryos in medium containing H-Y antibody and complement obtained from rat and guinea pig, respectively. The optimal condition for the activity of H-Y antibody was also investigated by culturing embryos in medium with different pH and complement concentration. The results obtained in these experiments were summarized as follows: 1. The formation rates of H-Y antibody in rats immunized with newborn testis and spleen cell were 40.0 and 50.0% respectively, and that in mouse immunized with spleen cell was 48.4%. 2. The activity of H-Y antibody was not affected by pH in range of 6.5 to 8.0, and the same was true for the relative concentration of complement to the H-Y antibody. 3. Minimum time needed for the activity of H-Y antibody was confirmed to be 0.5 to 1 hour and 24 to 48 hours respectively for the zona free embryos and intact embryos. 4. When mouse and rabbit embryos were treated with H-Y antibody obtained from rat, 46.4 and 54.8% of embryos were retarded or destroyed. From these results it could be said that H-Y antibody had strong interspecific cross reactivity.
The general and some pharmacological actions of DWP 302 were investigated in animals and the following results were obtained. In central nervous system, DWP 302 had no effects on the pentobarbital induced anaesthesia, locomotor activity, rotarod test, traction test, analgesic action in the mice and body temperature in the rat. DWP 302 showed no depressive action on the convulsion induced by strychnine and electronic shock. From these results, DWP 302 was considered to have no or little pharmacological effect on the central nervous system. Furthermore, DWP 302 had no influences on the normal blood pressure and heart rate. In the isolated ileum of guinea pig, DWP 302 showed neither contractive nor relaxing effects against the acetylcholine ($10^{-6}g/mι$), histamine ($10^{-6}g/mι$) and $BaCl_2$ ($10^{-4}g/mι$) at a concentration of $1.9{\times}10^{-4}g/mι$ in bath. But it caused a slight increase in basal tone at a concentration of $6.3{\times}10^{-4}g/mι$ and this effect was inhibited by atropine $10^{-7}g/mι.$ In the isolated trachea and vas deference, DWP 302 showed no effect on the contractions produced by histamine and norepinephrine, respectively. And DWP 302 showed no effect on the contractions produced by acetylcholine and oxytocin in the isolated nonpregnant rat uterus. DWP 302 had no effect on bile excretion, urine volume, pH and gastrointestinal motility, But, DWP 302 showed a significant inhibitory effect on gastric secretion in the rat.
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