• The Korean Journal of Physiology and Pharmacology
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• v.16 no.3
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• pp.187-192
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• 2012

In the present study, the antinociceptive profiles of hop extract were characterized in ICR mice. Hop extract administered orally (from 25 to 100 mg/kg) showed an antinociceptive effect in a dose-dependent manner as measured in the acetic acid-induced writhing test. Antinociceptive action of hop extract was maintained at least for 60 min. Moreover, cumulative response time of nociceptive behaviors induced with intraplantar formalin injection was reduced by hop extract treatment during the 2nd phases. Furthermore, the cumulative nociceptive response time for intrathecal injection of substance P ($0.7{\mu}g$) or glutamate ($20{\mu}g$) was diminished by hop extract. Intraperitoneal pretreatment with naloxone (an opioid receptor antagonist) attenuated antinociceptive effect induced by hop extract in the writhing test. However, methysergide (a 5-HT serotonergic receptor antagonist) or yohimbine (an ${\alpha}_2$-adrenergic receptor antagonist) did not affect antinociception induced by hop extract in the writhing test. Our results suggest that hop extract shows an antinociceptive property in various pain models. Furthermore, the antinociceptive effect of hop extract may be mediated by opioidergic receptors, but not serotonergic and ${\alpha}_2$-adrenergic receptors.

• Korean Journal of Plant Resources
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• v.23 no.6
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• pp.513-518
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• 2010

In the present study, the antinociceptive profiles of Dianthus chinensis L extract were examined in ICR mice. Dianthus chinensis L extract administered orally (200 mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, Dianthus chinensis L extract attenuated the writhing numbers in the acetic acid-induced writhing test. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of substance P ($0.7\;{\mu}g$) was diminished by Dianthus chinensis L extract. Intraperitoneal (i.p.) pretreatment with yohimbine ($\alpha_2$-adrenergic receptor antagonist) attenuated antinociceptive effect induced by Dianthus chinensis L extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by Dianthus chinensis L extract in the writhing test. Our results suggest that Dianthus chinensis L extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of Dianthus chinensis L extract may be mediated by $\alpha_2$-adrenergic receptor, but not opioidergic and serotonergic receptors.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.5
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• pp.285-289
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• 2010

In the present study, the antinociceptive profiles of $Campanula$ $punctata$ extract were examined in ICR mice. The $Campanula$ $punctata$ contain a large dose of saponin. $Campanula$ $punctata$ extract administered orally (200 mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, $Campanula$ $punctata$ extract attenuated the writhing numbers in the acetic acid-induced writhing test. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of substance P ($0.7{\mu}g$) was diminished by $Campanula$ $punctata$ extract. Intraperitoneal (i.p.) pretreatment with yohimbine (${\alpha}_2$-adrenergic receptor antagonist) attenuated antinociceptive effect induced by $Campanula$ $punctata$ extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by $Campanula$ $punctata$ extract in the writhing test. Our results suggest that $Campanula$ $punctata$ extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of $Campanula$ $punctata$ extract may be mediated by ${\alpha}_2$-adrenergic receptor, but not opioidergic and serotonergic receptors.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.2
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• pp.119-123
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• 2012

In the present study, the antinociceptive profiles of $Agrimonia$ $pilosa$ $Ledeb$ extract were examined in ICR mice. $Agrimonia$ $pilosa$ $Ledeb$ extract administered orally (200 mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, $Agrimonia$ $pilosa$ $Ledeb$ extract attenuated the writhing numbers in the acetic acid-induced writhing test. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of substance P (0.7 ${\mu}g$) was diminished by $Agrimonia$ $pilosa$ $Ledeb$ extract. Intraperitoneal (i.p.) pretreatment with yohimbine (${\alpha}_2$-adrenergic receptor antagonist) attenuated antinociceptive effect induced by $Agrimonia$ $pilosa$ $Ledeb$ extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by $Agrimonia$ $pilosa$ $Ledeb$ extract in the writhing test. Our results suggest that $Agrimonia$ $pilosa$ $Ledeb$ extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of $Agrimonia$ $pilosa$ $Ledeb$ extract may be mediated by ${\alpha}_2$-adrenergic receptor, but not opioidergic and serotonergic receptors.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.2
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• pp.175-180
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• 2013

Resveratrol is a phytoalexin found in grapes, red wine, and berries. Resveratrol has been known to have many beneficial health effects, such as anti-cancer, neuroprotective, anti-inflammatory, and life-prolonging effects. However, relatively little is known about the effects of resveratrol on the regulation of ligand-gated ion channels. We have previously reported that resveratrol regulates subsets of homomeric ligand-gated ion channels such as those of 5-$HT_{3A}$ receptors. The ${\gamma}$-aminobutyric $acid_C$($GABA_C$) receptor is mainly expressed in retinal bipolar cells and plays an important role in visual processing. In the present study, we examined the effects of resveratrol on the channel activity of homomeric $GABA_C$ receptor expressed in Xenopus oocytes injected with cRNA encoding human $GABA_C$ ${\rho}$ subunits. Our data show that the application of GABA elicits an inward peak current ($I_{GABA}$) in oocytes that express the $GABA_C$ receptor. Resveratrol treatment had no effect on oocytes injected with $H_2O$ or with $GABA_C$ receptor cRNA. Co-treatment with resveratrol and GABA inhibited $I_{GABA}$ in oocytes with $GABA_C$ receptors. The inhibition of $I_{GABA}$ by resveratrol was in a reversible and concentration-dependent manner. The $IC_{50}$ of resveratrol was $28.9{\pm}2.8{\mu}M$ in oocytes expressing $GABA_C$ receptor. The inhibition of $I_{GABA}$ by resveratrol was in voltage-independent and non-competitive manner. These results indicate that resveratrol might regulate $GABA_C$ receptor expression and that this regulation might be one of the pharmacological actions of resveratrol on the nervous system.

• Korean Journal of Medicinal Crop Science
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• v.18 no.4
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• pp.238-243
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• 2010

In the present study, the antinociceptive profiles of Viola tricolor L. (V. tricolor L.) extract were examined in ICR mice. V. tricolor L. extract administered orally (200mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, V. tricolor L. extract attenuated the writhing numbers in the acetic acid-induced writhing test. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of substance P (0.7 ${\mu}g$) was diminished by V. tricolor L. extract. Intraperitoneal (i.p.) pretreatment with yohimbine (${\alpha}_2$-adrenergic receptor antagonist) attenuated antinociceptive effect induced by V. tricolor L. extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by V. tricolor L. extract in the writhing test. Our results suggest that V. tricolor L. extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of V. tricolor L. extract may be mediated by ${\alpha}_2$-adrenergic receptor, but not opioidergic and serotonergic receptors.

• Biomolecules & Therapeutics
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• v.28 no.1
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• pp.83-91
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• 2020

Tryptamines are monoamine alkaloids with hallucinogenic properties and are widely abused worldwide. To hasten the regulations of novel substances and predict their abuse potential, we designed and synthesized four novel synthetic tryptamine analogs: Pyrrolidino tryptamine hydrochloride (PYT HCl), Piperidino tryptamine hydrochloride (PIT HCl), N,N-dibutyl tryptamine hydrochloride (DBT HCl), and 2-Methyl tryptamine hydrochloride (2-MT HCl). Then, we evaluated their rewarding and reinforcing effects using the conditioned place preference (CPP) and self-administration (SA) paradigms. We conducted an open field test (OFT) to determine the effects of the novel compounds on locomotor activity. A head-twitch response (HTR) was also performed to characterize their hallucinogenic properties. Lastly, we examined the effects of the compounds on 5-HTR1a and 5-HTR2a in the prefrontal cortex using a quantitative real-time polymerase chain reaction (qRT-PCR) assay. None of the compounds induced CPP in mice or initiated SA in rats. PYT HCl and PIT HCl reduced the locomotor activity and elevated the 5-HTR1a mRNA levels in mice. Acute and repeated treatment with the novel tryptamines elicited HTR in mice. Furthermore, a drug challenge involving a 7-day abstinence from drug use produced higher HTR than acute and repeated treatments. Both the acute treatment and drug challenge increased the 5-HTR2a mRNA levels. Ketanserin blocked the induced HTR. Taken together, the findings suggest that PYT HCl, PIT HCl, DBT HCl, and 2-MT HCl produce hallucinogenic effects via 5-HTR2a stimulation, but may have low abuse potential.