• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.311-317
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• 2001

In this work we have investigated the physiological effects of $MgCl_2$ in isolated atrium, papillary muscle, perfused heart and anesthesized guinea pig, The addition or infusion of $MgCl_2$ (0~20 mM or mg/kg) to perfused hearts and to anesthesized guinea pigs induced a marked and dose-dependent negative chronotropic effect. The sinoatrial node automaticity could also be reduced by $MgCl_2$. The addition of $MgCl_2$to isolated atria and to papillary muscles induced a marked and dose-dependent negative inotropic effect. The threshold voltage could be increased by $MgCl_2$in papillary muscle. Increasing $MgCl_2$ shortened the action potential duration (APD) in dose-dependent manner at 30% ($APD_{30}$) and 90% repolarization ($APD_{90}$) measured with conventional microelectrode technique in papillary muscle. In anesthesized guinea pig, the magnesium infusion resulted in a dose-dependent drop in blood pressure. These results suggested that magnesium is closely associated with cardiac physiological condition and exerts antiarrhythmic activities.

• The Journal of Internal Korean Medicine
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• v.11 no.1
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• pp.165-177
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• 1990

In order to study the effects of HWA GAE SAN known clinically for their effects of treatment for cough and asthma, the study was carried out to investigate the effect of HWA GAE SAN extract on the contractile force of isolated guinea pig trachea smooth muscle and elucidate its mechanism. The results were obtained as follows. 1. Preparation of isolated guinea pig trachea smooth muscle was suspended in the oxygeneted Kreb's Henseleit bicarbonate buffer solution at $37^{\circ}C$ and recorded the developed tension by the drug with the isometric transducer (Nacro F-60). The restin tension was approximately 0.5g. 2. The trachea smooth muscle in normal state showed a significant atony to the increase of density of HWA GAE SAN. 3. The atonic effect of the trachea smooth muscle was restricted after prescription of Pyrilamine& Cyproheptadine. Hireceptor broker, which were prearranged. 4. After 5, 15, 50& $150{\mu}l/ml$ of HWA GAE SAN were prescribed, the atony of trachea smooth muscle was caused by Histamine. 5. After 50& $150{\mu}l/ml$ of HWA GAE SAN were prescribed, the atony of trachea smooth muscle was remarkably dwindled which was caused by Acetylcholine. 6. After $150{\mu}l/ml$ of HWA GAE SAN were prescribed, the atony of trachea smooth muscle was remarkably dwindled which was caused by 5-Hydroxytryptamine.

• Korean Journal of Veterinary Research
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• v.55 no.4
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• pp.227-232
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• 2015

Akabane and bovine ephemeral fever (BEF) viruses cause vector-borne diseases. In this study, inactivated Akabane virus (AKAV)+Bovine ephemeral fever virus (BEFV) vaccines with or without recombinant vibrio flagellin (revibFlaB) protein were expressed in a baculovirus expression system to measure their safety and immunogenicity. Blood was collected from mice, guinea pigs, sows, and cattle that had been inoculated with the vaccine twice. Inactivated AKAV+BEFV vaccine induced high virus neutralizing antibody (VNA) titer against AKAV and BEFV in mice and guinea pigs. VNA titers against AKAV were higher in mice and guinea pigs immunized with the inactivated AKAV+BEFV vaccine than in animals inoculated with vaccine containing revibFlaB protein. Inactivated AKAV+BEFV vaccine elicited slightly higher VNA titers against AKAV and BEFV than the live AKAV and live BEFV vaccines in mice and guinea pigs. In addition, the inactivated AKAV+BEFV vaccine was safe, and induced high VNA titers, ranging from 1 : 64 to 1 : 512, against both AKAV and BEFV in sows and cattle. Moreover, there were no side effects observed in any treated animals. These results indicate that the inactivated AKAV+BEFV vaccine could be used in cattle with high immunogenicity and good safety.

• Journal of Environmental Health Sciences
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• v.35 no.4
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• pp.259-268
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• 2009

This study was carried out to investigate the protective effect of Red Ginseng Saponins on 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induced toxicities in guinea pigs ($200{\pm}10$ g). Normal control (NC) group guinea pigs ($200{\pm}10$ g) received vehicle and saline, while the TCDD-treated (TT) group was given water-extract (WE), saponin fraction (SF) and non-saponin fraction (NSF). Korean red ginseng fractions were administered from 1 week before TCDD-exposure for 4 weeks. Body weight loss and deteriorated clinical parameters related to sugar metabolism and liver function such as lipase and AST, respectively, these were significantly reduced by both saponin and non-saponin fractions. However, increase of lipase was attenuated by the saponin fraction in a dose-dependent manner. Only AST was affected by the saponin fraction. The results suggest that saponins are active substances in the Korean red ginseng water extract against TCDD induced toxicities in Guinea pigs.

• Journal of Nutrition and Health
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• v.25 no.7
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• pp.597-607
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• 1992

The present study examined effects of caffeine on coronary circulation myocardial oxygen me-tabolism and calcium release in isolated perfused guinea pig hearts. Intracoronary caffeine({{{{ {10 }^{-5 } }}}}∼{{{{ { 10}^{-3 } }}}}M) was employed for 10 minutes to measure coronary perfusate flow(CF) and coronary vascular sresistance(CVR) at a constant coronary perfusion pressure of 80 cmH2O Perfusate myocardial oxygen consumption(MVO2) and percent oxygen extraction(%EC2) were calcula-ted. In addition calcium contents in both perfusate samples were measured to calculate calcium release in coronary venous effluent. Caffeine significantly decreased CF and increased CVR during 10 minutes of caffeine perfusion regardless of dose of caffeine perfused exhibiting time-response. While % EO2 was significantly enhanced with caffeine MVO2 was markedly reduced. The coronary venous perfusate pH dcreased during the perfusion with caffeine. These changes were consistent with caffeine-induced metabolic acidosis. Calcium release appeared to be dose-dependent and high dose of caffeine greatly increased venous calcium release even 2 minutes after perfusion with carffeine. These finding in dicate that caffeine produced coronary vasoconst-riction with increased calcium release in isolated perfused guinea pig hearts. Additionaly this vasoconstrictor response mignt be due tin part to the direct actions of caffeine.

• International Journal of Oral Biology
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• v.43 no.2
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• pp.93-100
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• 2018

The investigation of the embryonic development of the cerebellum has a long history. The postnatal normal development of the cerebellum in rodents and other animals became a popular topic for morphological investigations nearly a century ago. However, surprisingly, only a few studies are available regarding the prenatal normal development of the rodent cerebellum, especially in guinea pigs. Cell proliferation is essential for the development of the nervous system. The assessment of cell proliferation can be achieved by using various methods. In this study, we investigated the cell proliferation of the cerebellar cortex in guinea pigs at different stages of pregnancy and in postnatal life. Fetuses were obtained by cesarean section at 50 or 60 days of gestation (dg). Immunohistochemistry was performed with proliferating cell nuclear antigen (PCNA) antibody in the cerebellum. Strong PCNA immunoreactivity was observed in the external granular layer (EGL), which is a neurogenic zone in the cerebellum. The proportion of PCNA-IR cells was greater at 1 week than at 60 dg in lobule I, but not lobule VIII. After 50 dg, the width of the EGL continued to decline until 1 week, due to the maturation of the EGL cells. These results demonstrate the pattern of PCNA immunoreactivity in the developing cerebellum of guinea pigs. This serves as a guideline to study abnormal cerebellum development.

• YAKHAK HOEJI
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• v.41 no.1
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• pp.139-146
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• 1997

In the present study, capsaicin-induced desensitization of peripheral sensory nerves were investigated by using guinea pig bronchi, in which these nerves are stimulated with cap saicin to produce a contractile response via the release of sensory neuropeptides such as substance P and neurokinin A. The contractile response to capsaicin was inhibited by the combination of CP96345 and SR 48968 suggesting that the excitatory effect of capsaicin is mediated via both the tachykinin NK-1 and NK-2 receptor. Capsaicin produced in vitro-desensitization in dose-dependent manner, but after this in vitro-desensitization the response to NK-1 and NK-2 receptor agonist did not change. Systemic administration (s.c.) of capsaicin also desensitized significantly bronchial tissues but could not produce any change in the contractile response to the selective agonists of NK-1 and NK-2 receptor. Therefore, the present results suggest that functional desensitization to capsaicin-induced contractile response in guinea pig bronchi does not involve NK-1 and NK-2 receptor, while excitatory effect of capsaicin is mediated via both NK-1 and NK-2 receptor. In conclusion, it is suggested that capsaicin- induced excitation and desensitization involves somewhat different pathways.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.91-98
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• 1992

Listeria monocytogenes antigens were detected with the avidinbiotinperoxidase complex(ABPC) method in formalin-fixed, paraffin-embedded tissues from experimentally infected rats, mice and guinea pigs. The anti-Lirteria monocytogenes serum used as first antibody was prepared by immunizing rabbits with Listeria monocytogenes serotype 1/2a. Rats, mice and guinea pigs that had been given inoculation of L monocytogenes(serotype 4b, Scott A strain) via intraperitoneally allotted to 3 groups. Rats were pretreated with the dexamethasone(DM-rats) for 7 consecutive days, mice and guinea pigs were inoculated intraperitoneally with L. monocytogenes At necropsy white necrotic foci of the liver, spleen and kidney were seen in mice and DM-rats, whereas not in guinea pigs. Organisms stained by the ABPC method were identified as pleomorphic dark brown staining structures in the livers, spleens and kidneys of mice and DM-rats. They were present in high numbers in center and peripherial regions of necrobiotic and necrotic foci of the liver and spleen as well as in glomerulus of the renal cortex. and liable tool for confirmative diagnosis of these bacterial diseases.

• Biomolecules & Therapeutics
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• v.3 no.4
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• pp.251-255
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• 1995

DA-3002 is a genuine human growth hormone produced by Dong-A Pharm. Co. Ltd. research laboratory using recombinant DNA technic. In this study, antigenic potential of DA-3002 was examined by active systemic anaphyaxis(ASA) in guinea pigs, mouse-rat passive cutaneous anaphylaxis(PCA) and passive hemagglutination(PHA) test as a part of safety research. DA-3002 induced anaphylactic shock in ASA test using guinea pigs Immunized with DA-3002 alone or DA-3002 incoporated into Freund's complete adjutant(FCA) when challenged with 10 times higher dose of anticipated clinical dose of DA-3002. In the mouse-rat PCA and PHA test, DA-3002 also showed positive results. DA-3002, therfore, was considered to produce IgE, IgG, and/or IgM in mice. The results of this study were similar to those of the other human growth hormones and these positive results were thought to be caused due to the fact that both DA-3002 and the other human growth hormones were heterogenous proteins to guinea pigs and mice. Considering the fact that DA-3002 is a genuine human growth hormone of which structure is identical with indigenous human growth hormone, DA-3002 is thought not to cause immunological problems in clinical use.

• The Korean Journal of Physiology
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• v.27 no.2
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• pp.139-150
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• 1993

We have reported that dopamine potentiates spontaneous contractions dose-dependently in guinea-pig antral circular muscle strips (Hwang et al, 1991). To clarify the underlying excitatory mechanism of dopamine on the gastric smooth muscle, the effects of dopamine on voltage-dependent $Ca^{2+}\;currents\;and\;Ca^{2+}\;-dependent\;K^+\;currents$ were observed in enzymatically dispersed guinea-pig gastric myocytes using the whole-cell voltage-clamp technique. Experiments were also done using isometric tension recording and conventional intracellular microelectrode techniques. 1) The effect of dopamine on the spontaneous contraction of antral circular muscle strips of the guinea-pig was excitatory in a dose-dependent manner, and was blocked by phentolamine, an ${\alpha}-adrenoceptor$ blocker. 2) The slow waves were not changed by dopamine. 3) The voltage-operated inward $Ca^{2+}$ current was not influenced by dopamine. 4) The $Ca^{2+}\;-dependent\;K^+$ outward current, which might reflect the changes of intracellular calcium concentration, was enhanced by dopamine. This effect was abolished by phentolamine. 5) The enhancing effect of dopamine on the $Ca^{2+}\;-dependent\;K^+$ current disappeared with heparin which is known to block the action of $InsP_3$. From these results, it is suggested that dopamine acts via $InsP_3-mediated\;Ca^{2+}$ mobilization from intracellular stores and such action potentiates the spontaneous contraction of guinea-pig gastric smooth muscle.