• Title/Summary/Keyword: Intracerebroventricular

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cAMP/PKA Agonist Restores the Fasting-Induced Down-Regulation of nNOS Expression in the Paraventricular Nucleus

  • Yoo, Sang-Bae;Lee, Seoul;Lee, Joo-Young;Kim, Bom-Taeck;Lee, Jong-Ho;Jahng, Jeong-Won
    • The Korean Journal of Physiology and Pharmacology
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    • v.16 no.5
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    • pp.333-337
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    • 2012
  • Gene expression of neuronal nitric oxide synthase (nNOS) changes in the hypothalamic paraventricular nucleus (PVN) depending on feeding conditions, which is decreased during food deprivation and restored by refeeding, and phosphorylated cAMP response element binding protein (pCREB) was suggested to play a role in its regulation. This study was conducted to examine if the fasting-induced down-regulation of the PVN-nNOS expression is restored by activation of cAMP-dependent protein kinase A (cAMP/PKA) pathway. Freely moving rats received intracerebroventricular (icv) injection of cAMP/PKA activator Sp-cAMP (40 nmol) or vehicle (sterilized saline) following 48 h of food deprivation. One hour after drug injections, rats were transcardially perfused with 4% paraformaldehyde, and the PVN tissues were processed for nNOS or pCREB immunohistochemistry. Sp-cAMP significantly increased not only nNOS but also pCREB immunoreactivities in the PVN of food deprived rats. Fastinginduced down-regulation of the PVN-nNOS was restored by 1 h after the icv Sp-cAMP. Results suggest that cAMP/PKA pathway may mediate the regulation of the PVN-nNOS expression depending on different feeding conditions.

Natriuresis Induced by Intracerebroventricular Diazepam in Rabbits

  • Koh, Jeong-Tae;Kook, Young-Johng
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.5
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    • pp.555-563
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    • 1998
  • The renal function is under regulatory influence of central nervous system (CNS), in which various neurotransmitter and neuromodulator systems take part. However, a possible role of central GABA-benzodiazepine system on the central regulation of renal function has not been explored. This study was undertaken to delineate the renal effects of diazepam. Diazepam, a benzodiazepine agonist, administered into a lateral ventricle (icv) of the rabbit brain in doses ranging from 10 to 100 ${\mu}g/kg,$ elicited dose-related diuresis and natriuresis along with improved renal hemodynamics. However, when given intravenously, 100 ${\mu}g/kg$ diazepam did not produce any significant changes in all parameters of renal function and systemic blood pressure. Diazepam, 100 ${\mu}g/kg$ icv, transiently decreased the renal nerve activity (RNA), which recovered after 3 min. The plasma level of atrial natriuretic peptide (ANP) increased 7-fold, the peak coinciding with the natriuresis and diuresis. Muscimol, a GABAergic agonist, 1.0 ${\mu}g/kg$ given icv, elicited marked antidiuresis and antinatriuresis, accompanied by decreases in systemic blood pressure and renal hemodynamics. When icv 0.3 ${\mu}g/kg$ muscimol was given 3 min prior to 30 ${\mu}g/kg$ of diazepam icv, urinary flow and Na excretion rates did not change significantly, while systemic hypotension was produced. These results indicate that icv diazepam may bring about natriuresis and diuresis by influencing the central regulation of renal function, and that the renal effects are related to the increased plasma ANP levels, not to the decreased renal nerve activity, and suggest that the effects may not be mediated by the activation of central GABAergic system.

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Effects of I.C.V Administration of Ethylcholine Aziridinuim(AF64A) on the Central Glutamatergic Nervous Systems in Rats

  • Ma, Young;Lim, Dong-Koo
    • Archives of Pharmacal Research
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    • v.20 no.1
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    • pp.39-45
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    • 1997
  • Changes in glutamatergic nervous activities following intracerebroventricular (icv) administration of ethylcholine aziridinium (AF64A) were studied in rats. The levels of total glutamate, those of glutamate in cerebrospinal fluid (CSF) and in extracellular fluid (ECF) of striatum, the activities of glutamine synthetase (GS), glutaminase and glutamate dehydrogenase (GDH) and the specific binding sites of $[^3H]$MK801 in striatum, hippocampus and frontal cortex were assessed a week after the infusion of AF64A (3 nmol) into lateral ventricle. The levels of total glutamate were significantly decreased in striatum, hippocampus and frontal cortex after AF64A treatment. Although the levels of glutamate in CSF weren't changed after AF64A treatment, the levels of glutamate in ECF of striatum were significantly decreased (62.6%). GS activities in striatum were significantly decreased. But, glutaminase activities in striatum were significantly increased. However, the activities of GS and glutaminase in frontal cortex and hippocampus weren't changed. Although GDH activities in frontal cortex were significantly decreased, those in striatum and hippocampus weren't altered. The striatal densities of $[^3H]$MK 801 binding sites were increased without changes in its affinity. Also, the specific binding sites of $[^3H]$MK801 were increased in frontal cortex but not in hippocampus. These results indicate that the glutamatergic nervous activities were altered with the infusion of AF64A into lateral ventricle. Furthermore, it suggest that the decreased levels of glutamate after AF64A treatment may affect the change in the other parameters of glutamatergic neuronal activities.

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Effects of Coptidis Rhizoma and Aconiti Lateralis Preparata Radix on the Change of Plasma Corticosterone Level and Rectal Temperature Induced by LPS (LPS에 의해 유발된 염증(炎症) 스트레스에 대한 황련(黃蓮)과 부자(附子)의 효과)

  • Cho, Eun-Ho;Lee, Tae-Hee
    • The Korea Journal of Herbology
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    • v.21 no.2
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    • pp.77-85
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    • 2006
  • Objectives : We investigated the effects of Coptidis Rhizoma and Aconiti Lateralis Preparata Radix on the LPS(Lipopolysaccharide) ICV(intracerebroventricular) injection. Methods : We measured plasma corticosterone level and rectal temperature in mice induced by I.C.V. injection of LPS (100ng/mouse). Results : The results were as follows.. 1. The plasma corticosterone levels in CR-1(0.5g/kg), CR-2(1.0g/kg), CR-3(3.0g/kg) were not decreased significant comparing with the control group.(P<0.05) 2. The plasma corticosterone level in AR-1(0.5g/kg) was decreased significant comparing with the control group.(P<0.05), but AR-2(1.0g/Kg) and AR-3(3.0g/kg) were not decreased significant comparing with the control group.(P<0.05). 3. The rectal temperature in CR-1(0.5g/kg), CR-2(1.0g/kg), CR-3(3.0g/kg) was decreased significant comparing with the control group.(P<0.05) 4. The rectal temperature in AR-1(0.5g/kg), AR-2(1.0g/kg), AR-3(3.0g/kg) was not decreased significant comparing with the control group.(P<0.05) Conclusion : These data revealed that Rhizoma Coptidis might have no significant effect on inflammation stress and Aconiti Lateralis Preparata Radix(0.5g/kg/mouse) might have significant effect on inflammation stress.

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Novel animal model for brain atrophy and protective effects of Korean ginseng (새로운 뇌 위축 동물 모델과 그 모델에서의 고려인삼의 보호 효과)

  • Kim, Myung-Gyou;Lee, Se-Na;Kim, Hyun-Mi;Chung, Joo-Ho;Leem, Kang-Hyun
    • The Korea Journal of Herbology
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    • v.21 no.4
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    • pp.197-205
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    • 2006
  • Objectives: Anti-oxidants are known to prevent neuronal diseases with pathological and physiological changes such as the brain atrophy and cognitive impairment. This study was designed to investigate the protective effects of Korean ginseng on the oxidative stress induced pathologic changes, and develop new animal model for the brain atrophy. Korean ginseng has anti-oxidant, anti-aging, and protective effects on the brain ischemia. Methods : The intracerebroventricular (ICV) hydrogen peroxide ($H_2O_2$) injection into mice was conducted to generate oxidative stress. Results : The ICV $H_2O_2$ (1 M, $5\;{\mu}l$ injection did not induce either convulsion or death in the acute phase. At the end of second week, cognitive impairment and pathologic change of the brain were observed. The massive brain atrophy was found in the $H_2O_2-injected$ mice, especially in the hippocampus and thalamus. Treatment with Korean ginseng showed a protective effect against the brain atrophy. The $H_2O_2$ injected mice revealed cognitive impairment in the passive avoidance test, and Korean ginseng alleviated cognitive impairment. Conclusion : The results indicate that Korean ginseng has a protective effect on the oxidative stress-induced neuronal damages.

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Effect of NMDA Receptor on Analgesic Effect of Bovine Milk-derived Lactoferrin (BLF) (우유속 락토페린의 NMDA 수용체를 통한 진통효과)

  • Jeon, Yong-Joon;Yun, Jae-Suk;Lim, Hwa-Kyung;Park, Ki-Suk;Na, Han-Kang;Kim, Dong-Sup;Kim, Joo-il;Yoon, Yea-Chang;Choi, Ki Hwan
    • YAKHAK HOEJI
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    • v.49 no.5
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    • pp.370-374
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    • 2005
  • Lactoferrin is a multifunctional protein that is found in milk, neutrophils, and other biological fluids, and its receptors have also been identified in the central nervous system. Recently, it was reported that bovine milk-derived lacto­ferrin (BLF) produced analgesia via a $\mu$-opioid receptor-mediated response in the spinal cord. However the precise mech­anism of this analgesic effect is remains unclear. In Randall-Selitto paw pressure study, each single administration of morphine (10 mg/kg) and BLF (50, 100 and 200 mg/kg) induced analgesia, however, NMDA receptor antagonist MK-801 (0.1, 0.2 and 0.3 mg/kg), inhibited analgesia induced by BLF (100 mg/kg). Intracerebroventricular infusion (I.C.V.) of N­methyl-D-aspartic acid (NMDA) ($0.3\;{\mu}g/8.0\;{\mu}l/hr/day$), as a NMDA receptor agonist, reversed inhibition of MK-801 (0.3 mg/kg) on analgesia induced by BLF (100 mg/kg). These results suggest that BLF have analgesic effect, through NMDA recep­tor activation.

Protective effects of Acanthopanax divaricatus extract in mouse models of Alzheimer's disease

  • Yan, Ji-Jing;Ahn, Won-Gyun;Jung, Jun-Sub;Kim, Hee-Sung;Hasan, Md. Ashraful;Song, Dong-Keun
    • Nutrition Research and Practice
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    • v.8 no.4
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    • pp.386-390
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    • 2014
  • BACKGROUND: Acanthopanax divaricatus var. albeofructus (ADA) extract has been reported to have anti-oxidant, immunomodulatory, and anti-mutagenic activity. MATERIALS/METHODS: We investigated the effects of ADA extract on two mouse models of Alzheimer's disease (AD); intracerebroventricular injection of ${\beta}$-amyloid peptide ($A{\beta}$) and amyloid precursor protein/presenilin 1 (APP/PS1)-transgenic mice. RESULTS: Intra-gastric administration of ADA stem extract (0.25 g/kg, every 12 hrs started from one day prior to injection of $A{\beta}1$-42 until evaluation) effectively blocked $A{\beta}1$-42-induced impairment in passive avoidance performance, and $A{\beta}1$-42-induced increase in immunoreactivities of glial fibrillary acidic protein and interleukin (IL)-$1{\alpha}$ in the hippocampus. In addition, it alleviated the $A{\beta}1$-42-induced decrease in acetylcholine and increase in malondialdehyde levels in the cortex. In APP/PS1-transgenic mice, chronic oral administration of ADA stem extract (0.1 or 0.5 g/kg/day for six months from the age of six to 12 months) resulted in significantly enhanced performance of the novel-object recognition task, and reduced amyloid deposition and IL-$1{\beta}$ in the brain. CONCLUSIONS: The results of this study suggest that ADA stem extract may be useful for prevention and treatment of AD.

Effect of Brain Angiotensin II Receptor Antagonists and Antisense Oligonucleotide on Drinking and Renal Renin in Rats

  • Cho, Hyeon-Kyeong;Yang, Eun-Kyoung;Han, Hee-Suk;Lee, Won-Jung;Phillips, M. Ian
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.2
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    • pp.137-142
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    • 2000
  • The physiological roles of brain angiotensin II in mediating water deprivation-induced drinking and in regulating renal renin release were assessed in male Sprague-Dawley rats. Specific $AT_1$ receptor antagonists, losartan and SK 1080, and antisense oligonucleotide (AS-ODN) directed to $AT_1$ receptor mRNA were intracerebroventricularly (i.c.v.) administered in conscious unrestrained rats. When water was given 20 min after i.c.v. injection of $AT_1$ receptor antagonists in 48-h water-deprived rats, losartan and SK 1080 produced approximatly 20% and 50% decrease in 1-h water intake, respectively. In contrast, i.c.v. treatment of the AS-ODN to $AT_1$ receptor mRNA for 24-h did not alter 1-h water intake in 24-h water-deprived rats, but prevented the increase in overnight water intake after 24-h water-deprivation. Six-day i.c.v. treatment of AS-ODN did not alter either the basal plasma renin concentration or renal cortical levels of renin and renin mRNA. The present results suggest that endogenous brain Ang II plays an important role in thirst and water intake through $AT_1$ receptors, but further studies are required to elucidate its regulatory role in renal renin synthesis.

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Inhibitory Effect of an Ethanol Extract Mixture of Vitis amurensis, Aralia cordata, and Glycyrrhizae radix on Amyloid β Protein (25-35)-Induced Neurotoxicity (머루전초, 독활전초, 감초 혼합추출물의 Amyloid β Protein (25-35) 유발 신경 독성에 대한 억제효과)

  • Jang, Ji Yeon;Seong, Yeon Hee
    • Korean Journal of Medicinal Crop Science
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    • v.22 no.2
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    • pp.105-112
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    • 2014
  • The present study investigated an ethanol extract (SSB) of a mixture of three medicinal plants of Vitis amurensis, Aralia cordata, and Glycyrrhizae radix for possible neuroprotective effects on neurotoxicity induced by Amyloid ${\beta}$ protein ($A{\beta}$) (25-35) in cultured rat cortical neurons and antidementia activity in mice. Exposure of cultured cortical neurons to $15{\mu}M$ $A{\beta}$ (25-35) for 36 h induced neuronal apoptotic death. At $1-30{\mu}g/m{\ell}$, SSB inhibited neuronal death, elevation of intracellular calcium concentration ($[Ca^{2+}]_i$), and generation of reactive oxygen species (ROS) induced by $A{\beta}$ (25-35) in cultured cortical neurons. Memory impairment and increase of acetylcholinesterase activity induced by intracerebroventricular injection of mice with 16 nmol $A{\beta}$ (25-35) was inhibited by chronic treatment with SSB (25, 50 and 100 mg/kg, p.o., for 8 days). From these results, it is suggested that antidementia effect of SSB is due to its neuroprotective effect against $A{\beta}$ (25-35)-induced neurotoxicity and that SSB may have a therapeutic role in preventing the progression of Alzheimer's disease.

Protective Effects of Ginsenoside Rg3 against Cholesterol Oxide-Induced Neurotoxicity in the Rat

  • Kim, Jong-Hoon
    • Journal of Ginseng Research
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    • v.33 no.4
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    • pp.294-304
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    • 2009
  • Ginsenosides are among the most well-known traditional herbal medicines frequently used for the treatment of various symptoms in South Korea. The neuroprotective effects of ginsenoside $Rg_3$ (G-$Rg_3$) on cholesterol-oxide-(CO)-induced neurotoxicity were investigated through the analyses of rat brains. The recently accumulated reports show that ginseng saponins (GTS), the major active ingredients of Panax ginseng, have protective effects against neurotoxin insults. In the present study, the neuroprotective effects of G-$Rg_3$ on CO-induced hippocampal excitotoxicity were examined in vivo. The in-vitro studies using rat cultured hippocampal neurons revealed that G-$Rg_3$ treatment significantly inhibited CO-induced hippocampal cell death. G-$Rg_3$ treatment not only significantly reduced CO-induced DNA damage but also attenuated CO-induced apoptosis. The in-vivo studies that were conducted revealed that the intracerebroventricular (i.c.v.) pre-administration of G-$Rg_3$ significantly reduced i.c.v. CO-induced hippocampal damage in rats. To examine the mechanisms underlying the in-vitro and in-vivo neuroprotective effects of G-$Rg_3$ against CO-induced hippocampal excitotoxicity, the effect of G-$Rg_3$ on the CO-induced elevations of the apoptotic cells in cultured hippocampal cells was examined, and it was found that G-$Rg_3$ treatment inhibited CO-induced apoptosis. The histopathological evaluation demonstrated that G-$Rg_3$ significantly diminished the apoptosis in the hippocampus and also spared the hippocampal CA1, CA3, and dentate gyrus neurons. G-$Rg_3$ also significantly improved the CO-caused behavioral impairment. G-$Rg_3$ itself had no effect, however, on the CO-induced inhibition of succinate dehydrogenase activity (data not shown). These results collectively indicate the G-$Rg_3$-induced neuroprotection against CO in rat hippocampus. With regard to the wide use of G-$Rg_3$, this agent is potentially beneficial in treating CO-induced brain injury.