• Title/Summary/Keyword: 5-$HT_{2A}$ receptor

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The Analgesic Effect of Bee Venom Acupuncture and Its Mechanism on the Type II Collagen-Induced Arthritis Rats

  • Seo, Byung-Kwan;Baek, Yong-Hyun;Choi, Do-Young;Park, Dong-Suk
    • Journal of Acupuncture Research
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    • v.22 no.2
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    • pp.19-32
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    • 2005
  • Objectives : to evaluate the analgesic effect of bee venom acupuncture on Choksamni (ST36) in the collagen-induced arthritis rats and investigate the role played by serotonergic receptor subtypes (5-HT1a, 5-HT2a) in the antinociceptive effect of bee venom acupuncture in a thermal hyperalgesia test Methods : Experiments were performed on 5 week-aged 60 male Sprague-Dawley rats according to National Institute of Health guidelines and the ethical guidelines of the International Association for the Study of Pain (IASP). Arthritis was induced with arthrogenic collagen emulsion (Bovine type II collagen ${\mu}g$ with incomplete Freund's adjuvant $100\;{\mu}g$). The onset of arthritis was considered to be present when erythema and swelling were detected in at least one joint. The thermal hyperalgesia was evaluated weekly with tail flick test in the rats of severity grade 3 without any injury at tail and foot (including inflammation, ulceration, snap). In the fourth week after first immunization, the analgesic effect of bee venom acupuncture (Choksamni, ST36) was measured with consecutive tail flick latency after intraperitoneal injection of spiroxatrine (1mg/kg) and spiperone (1mg/kg). Results : Chronic inflammatory pain was induced as time elapsed after the immunization of arthrogenic collagen and the maximum value was reached from third to fifth week. Chronic inflammatory pain induced by CIA was inhibited by bee venom acupuncture on the left ST36. The analgesic effect of bee venom acupuncture was inhibited by intraperitoneal injection of 5-HT1a antagonist spiroxatrine and 5-HT2a antagonist spiperone. Conclusions : Therefore, a conclusion. that the analgesic effect of bee venom acupuncture in the chronic inflammatory pain is partially mediated by 5-HT1a and 5-HT2a receptors can be made.

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Developmental Disability Animal Model Based on Neonatal Lipopolysaccharide with Altered 5-HT Function

  • Kim, Jae-Goo;Kim, Min-Soo;Lee, Se-Oul;Kim, Gun-Tae;Lee, Jong-Doo;Kim, Dong-Goo
    • The Korean Journal of Physiology and Pharmacology
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    • v.11 no.3
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    • pp.113-119
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    • 2007
  • Developmental disability shows life-long behavioral abnormality with no significant physical malformation. This study was undertaken to develop an animal model for developmental disability by using two-factor approach. Lipopolysaccharide (LPS), a bacterial toxin, and NAN-190, a $5-HT_{1A}$ receptor antagonist, were administered to Sprague-Dawley rats on postnatal day (PND) 5 to induce inflammation and an altered 5-HT system, respectively. Long-term alteration of behavior occurred in the drug-treated groups. The LPS-treated group showed impaired motor coordination in the Rota-rod test. The LPS- treated or both LPS and NAN-190-treated groups showed impaired fore-paw muscle power in the wire maneuver test. These groups also showed decreased white matter volume and increased serotonergic fibers. The LPS and NAN-190-treated group also exhibited neurologic deficit in the placing reaction test and impaired equilibrium function in the tilt table test. The results showed that a variety of altered behaviors can be generated by two factor model, and suggested that combination of important etiologic factors and possible underlying defects is a promising strategy of establishing an animal model for developmental disabilities.

Calcium Signaling of Dioleoyl Phosphatidic Acid via Endogenous LPA Receptors: A Study Using HCT116 and HT29 Human Colon Cancer Cell Lines

  • Chang, Young-Ja;Kim, Hyo-Lim;Sacket, Santosh J.;Kim, Kye-Ok;Han, Mi-Jin;Jo, Ji-Yeong;Im, Dong-Soon
    • Biomolecules & Therapeutics
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    • v.15 no.3
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    • pp.150-155
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    • 2007
  • In the present study, we have tested the effect of dioleoyl phosphatidic acid (PA) on intracellular $Ca_{2+}$ concentration ($[Ca^{2+}]_{i}$) in two human colon cancer cell lines (HCT116 and HT29). PA and lysophosphatidic acid (LPA), a bioactive lysolipid, increased $[Ca^{2+}]_{i}$ in both HCT116 and HT29 cell lines. Increases of $[Ca^{2+}]_{i}$ by PA and LPA were more robust in HCT116 cells than in HT29 cells. A specific inhibitor of phospholipase C (U73122), however, was not inhibitory to the cell responses. Pertussis toxin, a specific inhibitor of $G_{i/o}$ type G proteins, however, had an inhibitory effect on the responses except for an LPA-induced one in HT29 cells. Ruthenium red, an inhibitor of the ryanodine receptor, was not inhibitory on the responses, however, 2-APB, a specific inhibitor of inositol 1,4,5-trisphosphate receptor, completely inhibited both lipid-induced $Ca^{2+}$ increases in both cell types. Furthermore, by using Ki16425 and VPC32183, two structurally dissimilar specific antagonists for $LPA_{1}/LPA_{3}$ receptors, an involvement of endogenous LPA receptors in the $Ca^{2+}$ responses was observed. Ki16425 completely inhibited the responses but the susceptibility to VPC32183 was different to PA and LPA in the two cell types. Expression levels of five LPA receptors in the HCT116 and HT29 cells were also assessed. Our data support the notion that PA could increase $[Ca^{2+}]_{i}$ in human colon cancer cells, probably via endogenous LPA receptors, G proteins and $IP_{3}$ receptors, thereby suggesting a role of PA as an intercellular lipid mediator.

Toluene Inhalation Causes Early Anxiety and Delayed Depression with Regulation of Dopamine Turnover, 5-HT1A Receptor, and Adult Neurogenesis in Mice

  • Kim, Jinhee;Lim, Juhee;Moon, Seong-Hee;Liu, Kwang-Hyeon;Choi, Hyun Jin
    • Biomolecules & Therapeutics
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    • v.28 no.3
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    • pp.282-291
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    • 2020
  • Inhaled solvents such as toluene are of particular concern due to their abuse potential that is easily exposed to the environment. The inhalation of toluene causes various behavioral problems, but, the effect of short-term exposure of toluene on changes in emotional behaviors over time after exposure and the accompanying pathological characteristics have not been fully identified. Here, we evaluated the behavioral and neurochemical changes observed over time in mice that inhaled toluene. The mice were exposed to toluene for 30 min at a concentration of either 500 or 2,000 ppm. Toluene did not cause social or motor dysfunction in mice. However, increased anxiety-like behavior was detected in the short-term after exposure, and depression-like behavior appeared as delayed effects. The amount of striatal dopamine metabolites was significantly decreased by toluene, which continued to be seen for up to almost two weeks after inhalation. Additionally, an upregulation of serotonin 1A (5-HT1A) receptor in the hippocampus and the substantia nigra, as well as reduced immunoreactivity of neurogenesis markers in the dentate gyrus, was observed in the mice after two weeks. These results suggest that toluene inhalation, even single exposure, mimics early anxiety-and delayed depression-like emotional disturbances, underpinned by pathological changes in the brain.

Effects of Ginsenoside Total Saponins on Experimental Irritable Bowel Syndrome in Rats

  • Kim, Jong-Hoon;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.29 no.2
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    • pp.94-99
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    • 2005
  • In the previous study, we reported that the in viかo inhibitory effect of ginsenosides, active ingredient of Panax ginseng, on $5-HT_{3A}$ receptor channel activity is coupled to in vivo anti-vomiting and anti-nausea effect. In the present study, we further investigated that the inhibitory effect of ginsenosides, active ingredient of Panax ginseng, on 5-HT3A receptor channel activity is also coupled to attenuation of irritable bowel syndrome (IBS), which is induced by colorectal distention (CRD) and $0.6\%$ acetic acid treatment. The CRD-induced visceral pains induced by CRD and acetic acid treatment are measured by frequency of contractions of the external oblique muscle in conscious rats. Treatment of GTS significantly inhibited CRD-induced visceral pain with dose-dependent manner. The $EC_{50}$ was $5.5{\pm}4.7$ mg/kg ($95\%$ confidence intervals: 1.2-15.7) and the antinociceptive effect of GTS on visceral pain was persistent for 4 h. We also compared the effects of protopanaxadiol (PD) ginsenosides and protopanaxatriol (PT) ginsenosides with saline on acetic acid-and CRD-induced visceral pain, and found that protopanaxatriol (PT) ginsenosides was much more potent than PD ginsenosides in attenuating CRD-induced visceral pain. These results indicate that U ginsenosides of Panax ginseng are components far attenuation of experimentally CRD-induced visceral pains.

Effects of Intracerebroventricular TFMPP on Rabbit Renal Function (뇌실내 TFMPP가 가토신장기능에 미치는 효과)

  • Lim, Young-Chai;Choi, Johng-Bom;Kim, Kyung-Keun;Kook, Young-Johng
    • The Korean Journal of Pharmacology
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    • v.28 no.2
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    • pp.137-146
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    • 1992
  • The central tryptaminergic system has been shown to play an important role in the regulation of renal function: $5-HT_1$ receptor mediate diuresis and natriuresis, whereas both $5-HT_2$ and $5-HT_3$ mediate antidiuresis and antinatriuresis. Recently, $5-HT_1$ receptors are further subdivided into many subtypes, and central $5-HT_{1A}$ subtype was shown to mediate diuretic and natriuretic effects. The present study was undertaken to delineate the role of $5-HT_{1B}$ subtype. Trifluoromethylphenylpiperazine (TFMPP), a selective $5-HT_{1B}$ agonist in doses ranging from 8 to $750\;{\mu}g/kg$ icv elicited diuresis, natriuresis and kaliuresis in dose-dependent fashion, with the fractional excretion of filtered Na reaching 5.44% with $250\;{\mu}g/kg$ icv. The natriuresis outlasted the transient increases in renal hemodynamics, suggesting humoral mediation in the decreased tubular Na reabsorption. Plasma concentration of atrial natriuretic peptide increased along with the natriuresis. Systemic blood pressure transiently increased. When given intravenously, no diuresis and natriuresis was elicited, indicating the central mechanism. The icv TFMPP effects were not significantly affected by icv methysergide, a nonselective $5-HT_1$ blocker. Both ketanserin and MDL 72222, selective $5-HT_2$ and $5-HT_3$ antagonists, resp., did not abolish the TFMPP effects. Nor did NAN-190, $5-HT_{1A}$ blocker, affect the TFMPP effects. These observations suggest that central $5-HT_{1B}$ receptors may play a role in the central regulation of renal function by exerting diuretic and natriuretic influences, mainly through natriuretic factors.

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Determination of Novel Synthetic 5HT2C Agonist KOPC20010 by Gas-Chromatography/Mass Spectrometry and its Bioavailability in Sprague-Dawley Rats

  • Im, Hye-Yeon;Pae, Ae-Nim;Yang, Ha-Yun;Park, Woo-Kyu;Seo, Ji-Eun;Haque, Md. Mamunul;Kwon, Oh-Seung
    • Journal of Pharmaceutical Investigation
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    • v.41 no.1
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    • pp.31-36
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    • 2011
  • $5HT_{2C}$ receptor among fourteen 5-HT subtypes plays important roles in several disorders such as depression, anxiety, epilepsy, schizophrenia and sleep disorders. The purpose of the study is to investigate pharmacokinetic parameters and bioavailability of a newly synthesized selective agonist of $5-HT_{2C}$ receptor, KOPC-20010 (KP10) in rats after intravenous and oral administration for the development of therapeutic anti-obesity agents. KP10 was administered orally (40 mg/kg) or intravenously (20 mg/kg), blood was collected via a catheter, and analyzed by GC/MSD. The calibration curve of KP10 in plasma and urine showed high linearity ($r^2$ >0.999). The retention times of KP10 in plasma and urine were 8.7 and 9.7 min, respectively. After oral administration of 40 mg/kg, pharmacokinetic parameters were calculated as follows; $C_{max}$ value was $1242.9{\pm}1195.5$ ng/mL at $1.1{\pm}0.6$ hr ($T_{max}$). $AUC_{0->24hr}$ and $AUC_{0>{\infty}}$ were $8034.2{\pm}960.7$ and $10464.1{\pm}681.5\;ng{\cdot}hr/mL$, respectively. The terminal half-life was $21.9{\pm}7.6$ hr. $AUC_{0->24hr}$ and $AUC_{0>{\infty}}$ were $4292.4{\pm}523.0$ and $6111.2{\pm}756.2\;ng{\cdot}hr/mL$, respectively, after 20 mg/kg of intravenous administration. The terminal half-life after intravenous administration was $25.1{\pm}9.4$ hr. Bioavailability of KP10 was determined to 86%. The excretion amount into the urine within 48 hr was approximately 4.7 to 6.7% of the dose administered. These data may be beneficial to the anti-obesity drug development of KP10.

Nefazodone and Associated Perceptual Disturbance : A Report of Four Cases (Nefazodons투여 후 지각이상을 보인 환자 4례)

  • Kim, Ji-Yun;Song, Hyoung-Seok;Cho, Bang-Hyun;Kim, Yong-Ku
    • Korean Journal of Biological Psychiatry
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    • v.6 no.2
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    • pp.259-263
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    • 1999
  • Nefazodone, a newer antidepressant is a phenylpiperazine derivative that inhibits the reuptake of both norepinephrine and serotonin, and antagonizes $5-HT_{2A}$ and ${\alpha}_1$ adrenergic receptors. Compared with SSRIs, nefazodone caused the fewer activating symptoms, adverse gastrointestinal effects(nausea, diarrhea, anorexia) and adverse effects of sexual function, but is associated with the more dizziness, dry mouth, constipation, visual disturbances and confusion. We report on 4 cases of visual disturbances and hallucinations in patients taking nefazodone. It is not certain what mechanisms mediated these side effects, but three mechanisms are possible. 1) Nefazodone, as a 5-HT2 antagonist, might induce visual disturbances. 2) mCPP, metabolite of nefazodone might contribute to the hallucination through action on 5-HT receptor. 3) Dopaminergic enhancing activity of nefazodone might cause hallucination. These case report raises the possibility that dose-related perceptual disturbances may exist with nefazodone. The fact emphasizes the need to pay close attention to all possible drug interactions, particularly in patients treated with multiple psychoactive agents, older patients, and patients with decreased hepatic function.

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The Inhibitory Mechanism of Gentamicin on Electrical Field Stimulation Response in Rat Bladder Smooth Muscle

  • Min, Chang Ho;Wang, YiYi;Bae, Jinhyung;Han, Jung Hoon;Sohn, Uy Dong
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.5
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    • pp.473-478
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    • 2015
  • To see the inhibitory mechanism of gentamicin in response to electrical field stimulation (EFS) using the rat bladder smooth muscle, atropine or guanethidine was treated but had no effect. Methylsergide, a non-selective 5-$HT_1$, 5-$HT_2$ receptor antagonist was also treated but had on effect. Kinase inhibitors, such as chelerythrine (PKC inhibitor), ML-9 (MLCK inhibitor), or Y27632 (rho kinase inhibitor) were pretreated before gentamicin treatment, but did not have effect. For U73122, a phospholipase C (PLC) inhibitor however, the inhibitory effect to gentamicin was significantly attenuated in all frequencies given by the EFS. Therefore gentamicin induced inhibitory effect on EFS response in rat bladder smooth muscle was not mediated by the activation of adrenergic, cholinergic, or serotonergic receptor. The inhibition of gentamicin might be mediated through the PLC dependent pathway, but not through the PKC, MLCK or rho kinase dependent pathway.

Does ginsenoside act as a ligand as other drugs do?

  • Nah, Seung-Yeol
    • Proceedings of the Ginseng society Conference
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    • 2005.11a
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    • pp.32-40
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    • 2005
  • The last two decades have shown a marked expansion in publications of diverse effects of Panax ginseng. Ginsenosides, as active ingredients of Panax ginseng, are saponins found in only ginseng. Recently, a line of evidences shows that ginsenosides regulate various types of ion channel activity such as Ca$^{2+}$, K$^+$, Na$^+$, Cl$^-$, or ligand gated ion channels (i.e. 5-HT$_3$, nicotinic acetylcholine, or NMDA receptor) in neuronal, non-neuronal cells, and heterologously expressed cells. Ginsenosides inhibit voltage-dependent Ca$^{2+}$, K$^+$, and Na$^+$ channels, whereas ginsenosides activate Ca$^{2+}$-activated Cl$^-$ and Ca$^{2+}$-activated K$^+$ channels. Ginsenosides also inhibit excitatory ligand-gated ion channels such as 5-HT$_3$. nicotinic acetylcholine, and NMDA receptors. This presentation will introduce recent findings on the ginsenoside-induced differential regulations of ion channel activities as a ligand as other drugs do.

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