• 대한약리학회지
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• 제31권2호
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• pp.145-152
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• 1995

The effects and interactions of $4{\beta}-phorbol$ 12,13-dibutyrate(PDB) and polymyxin B(PMB) with adenosine on the electrically-evoked norepinephrine (NE) release were studied in the rat hippocampus. Slices from the rat hippocampus were equilibrated with $^3H-noradrenaline$ and the release of the labelled product, $^3H-NE$, which evoked by electrical stimulation$(3\;Hz,\;2\;ms,\;5\;VCm^{-1},\;rectangular\;pulses)$ was measured. PDB$(0.3{\sim}10\;{\mu}M)$, a selective protein kinase C(PKC) activator, increased the evoked NE release in a dose related fashion while increasing the basal rate of release. And the effects of $1\;{\mu}M$ PDB were significantly inhibited by $0.3\;{\mu}M$ tetrodotoxin(TTX) pretreatment or $Ca^{++}-free$ medium. $PMB(0.03{\sim}1\;mg)$, a specific PKC inhibitor, decreased the NE release in a dose dependent manner while increasing the basal rate of release. Adenosine $(1{\sim}10\;{\mu}M)$ decreased the NE release without changing the basal rate of release, and this effect was significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine$(2\;{\mu}M)$, a selective $A_1-receptor$ antagonist, treatment. Also, adenosine effects were significantly inhibited by PDB-and PMB-pretreatment. These results suggest that the PKC plays a role in the NE release in the rat hippocampus and might be participated in a post-receptor mechanism of the $A_1-adenosine$ receptor.

• The Korean Journal of Physiology and Pharmacology
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• 제15권5호
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• pp.285-289
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• 2011

Shilajit, a medicine herb commonly used in Ayurveda, has been reported to contain at least 85 minerals in ionic form that act on a variety of chemical, biological, and physical stressors. The substantia gelatinosa (SG) neurons of the trigeminal subnucleus caudalis (Vc) are involved in orofacial nociceptive processing. Shilajit has been reported to be an injury and muscular pain reliever but there have been few functional studies of the effect of Shilajit on the SG neurons of the Vc. Therefore, whole cell and gramicidin-perfotrated patch clamp studies were performed to examine the action mechanism of Shilajit on the SG neurons of Vc from mouse brainstem slices. In the whole cell patch clamp mode, Shilajit induced short-lived and repeatable inward currents under the condition of a high chloride pipette solution on all the SG neurons tested. The Shilajit-induced inward currents were concentration dependent and maintained in the presence of tetrodotoxin (TTX), a voltage gated $Na^+$ channel blocker, CNQX, a non-NMDA glutamate receptor antagonist, and AP5, an NMDA receptor antagonist. The Shilajit-induced responses were partially suppressed by picrotoxin, a $GABA_A$ receptor antagonist, and totally blocked in the presence of strychnine, a glycine receptor antagonist, however not affected by mecamylamine hydrochloride (MCH), a nicotinic acetylcholine receptor antagonist. Under the potassium gluconate pipette solution at holding potential 0 mV, Shilajit induced repeatable outward current. These results show that Shilajit has inhibitory effects on the SG neurons of Vc through chloride ion channels by activation of the glycine receptor and $GABA_A$ receptor, indicating that Shilajit contains sedating ingredients for the central nervous system. These results also suggest that Shilajit may be a potential target for modulating orofacial pain processing.

• The Korean Journal of Physiology and Pharmacology
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• 제15권5호
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• pp.267-272
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• 2011

A number of studies have demonstrated that 5-hydroxytryptamine (5-HT) can induce muscle contraction or relaxation response and enhance secretion in the gastrointestinal tract via a multiplicity of 5-HT receptor subtypes. In the present study, we investigated the pharmacological characterization of the 5-HT-induced contractile response in longitudinal smooth muscle isolated from the feline ileum. Addition of 5-HT into muscle chambers enhanced the basal tone and spontaneous activity in a concentration-dependent manner. The neurotoxin tetrodotoxin did not alter the 5-HT-induced contraction of the longitudinal muscles. Neither atropine nor guanethidine affected the contraction. The 5-HT agonists, 5-methylserotonin hydrochloride and mosapride, also evoked concentration-dependent contractions. The 5-HT-induced contraction was enhanced by the $5HT_2$ receptor antagonist ketanserin and the $5-HT_3$ receptor antagonist ondansetron but was inhibited by the 5-$HT_1$ receptor antagonist methysergide and 5-$HT_4$ receptor antagonist GR113808. These results indicate that 5-$HT_1$ and 5-$HT_4$ receptors may mediate the contraction of the 5-HT-induced response and 5-$HT_2$ and 5-$HT_3$ receptors may mediate 5-HT-induced relaxation in feline ileal longitudinal smooth muscles.

• The Korean Journal of Physiology and Pharmacology
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• 제24권5호
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• pp.433-440
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• 2020

The substantia gelatinosa (SG) of the trigeminal subnucleus caudalis (Vc) is the first relay site for the orofacial nociceptive inputs via the thin myelinated Aδ and unmyelinated C primary afferent fibers. Borneol, one of the valuable time-honored herbal ingredients in traditional Chinese medicine, is a popular treatment for anxiety, anesthesia, and antinociception. However, to date, little is known as to how borneol acts on the SG neurons of the Vc. To close this gap, the whole-cell patch-clamp technique was applied to elucidate the antinociceptive mechanism responding for the actions of borneol on the SG neurons of the Vc in mice. In the voltage-clamp mode, holding at -60 mV, the borneol-induced non-desensitizing inward currents were not affected by tetrodotoxin, a voltage-gated Na⁺ channel blocker, 6-cyano-7-nitro-quinoxaline-2,3-dione, a non-N-methyl-ᴅ-aspartate (NMDA) glutamate receptor antagonist and DL-2-amino-5-phosphonopentanoic acid, an NMDA receptor antagonist. However, borneol-induced inward currents were partially decreased in the presence of picrotoxin, a γ-aminobutyric acid (GABA)_A receptor antagonist, or strychnine, a glycine receptor antagonist, and was almost suppressed in the presence of picrotoxin and strychnine. Though borneol did not show any effect on the glycine-induced inward currents, borneol enhanced GABA-mediated responses. Beside, borneol enhanced the GABA-induced hyperpolarization under the current-clamp mode. Altogether, we suggest that borneol contributes in part toward mediating the inhibitory GABA and glycine transmission on the SG neurons of the Vc and may serve as an herbal therapeutic for orofacial pain ailments.

• Archives of Pharmacal Research
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• 제18권2호
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• pp.121-128
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• 1995

The role of nitric oxide (NO) in non-adrenegic non-cholinergic (NANC) neurotransmission was studied on circular muscle strips of the dorsal part of the fuinea-pig gastric fundus. In the presence of atropine and guanethidine, a low frequency-dependent relaxsations which were not affected by adrenergic and cholinergic blockage but abolished by tetrodotoxin. $N^G$-nitro-L-arginine (L-NNA), a stereospecific inhibitor of NO-biosynthesis, inhibited the relaxations induced by electrical stiumulations but not the relaxations to exogenous nitric oxide. The effect of L-NNA was prevented by L-arginine, the precursor of the NO biosynthesis but not by its enantiomer, D-arginine. Exgenous administration of No caused concentration -dependent relaxations which showed a similarity to those obtained with electrical simultaion. Hemoglobin, a NOscavenger, abolished the NO-induced relaxations and also markedly reduced those induced by electrical simultaion. The inhibitory effect os hemoglobin was similar to that of L-NNA. Application of ATP caused weak relaxations compared with those to electrical stimultaion, which were unaffected by L-NNA. Exogenously applied vasoactive intestinal polypeptide (VIP) induced concentration-dependent relaxation which was not affected by L-NNA. These results suggest that NO is produced and released mainly as a neurotransmitter from enteric neurons during NANC relaxation induced by low frequencies and short trains of electrical simulation and has a main role in NANC neurotransmission at relaxation induced by these electrical simultaions in the guinea-pig gastric fundus.

• 한국어병학회지
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• 제14권1호
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• pp.46-53
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• 2001

본 연구에서는 경골어류인 나일틸라피아(Oreochromis niloticus)와 이스라엘잉어(Cyprinus carpio)의 장관에 대한 neurokinin-1(NK-1)수용체 효능제인 substance p(SP)와 neurokinin-2(NK-2)수용체 효능제인 neurokinin A(NKA)의 수축활성과 작용기전을 비교 분석하였다. SP와 NKA는 모두 나일틸라피아와 이스라엘잉어의 장관 평활근에 대하여 농도 의존적인 수축반응을 나타내었다. 그러나 이들에 의한 수축반응의 경향은 어종에 따라 다르게 나타났다. 즉, 나일틸라피아 장관 평활근에 대하여서는 SP가 NKA에 비하여 높은 친화력과 효능을 나타내었으나, 이스라엘잉어의 장관 평활근에 대하여서는 SP와 NKA의 수축반응은 유의한 차이가 없었다. 나일틸라피아 및 이스라엘잉어의 장관 평활근에 대한 SP와 NKA의 수축반응들은 모두 NK-1 수용체 차단제인 L-732,138에 의해서는 비경쟁적으로 길항되었으나, NK-2 수용체 차단제인 MDL 29913에 의해서는 영향을 받지 않았다. 한편, 선택적 무스카린성 수용체 길항제인 atropine($5{\times}10^{-7}$M)및 신경절 차단제인 tetrodotoxin($2{\times}10^{-7}$M)은 나일틸라피아 및 이스라엘잉어의 장관 평활근에 있어서 SP에 의해 유발된 수축반응들은 모두 유의성 있게 억제시켰으나, NKA에 의해 유발된 수축반응들에 대하여서는 유의성 있는 영향을 나타내지 않았다. 이상의 결과들을 종합하여 보면, SP및 NKA는 모두 어류의 장관 평활근에 대하여 강력한 수축효과를 나타내나 그 작용기전은 다르다고 추정된다. 즉, SP및 NKA의 장관 수축작용은 주로 장관 평활근에 존재하는 NK-1 수용체를 매개한 직접적인 작용에 기인하는 것으로 사료되나 SP의 경우에는 tachykinin 수용체를 통한 직접작용 이외에도 콜린성 신경말단(cholinergic nerve terminal)을 자극하는 간접적인 경로도 관여하는 것으로 추정된다.

• 대한약리학회지
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• 제32권3호
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• pp.357-371
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• 1996

리튬(Lithium)은 임상에서 조울병 치료에 이용되고 있다. 본 연구는 흰쥐 적출 관류부신 으로부터 catecholamine (CA) 분비에 대한 리튬의 작용을 검색 하고 그 기전을 규명하고자 하여 얻어진 결과는 다음과 같다. 정상 Krebs-bicarbonate 용액내의 $Na^+$ (118.4 mM)을 리튬으로 대치하여 관류하였을때 CA 분비는 점차적인 증가를 나타내었으며, $30{\sim}60$분에서 최대 분비작용을 나타내었다. Li-Krebs액은 모든 실험에서 부신정맥을 통해서 2시간동안 관류하였다. Li-Krebs에 의한 CA 분비반응은 $Ca^{++}-free$ Krebs액으로 전처치한 상태에서 유의하게 억제되었다. 이와같은 Li-Krebs 액에 의한 CA 분비작용은 nicardipine ($10^{-6}$ M), TMB-8 ($10^{-5}$ M) 및 chlorisondamine ($10^{-6}$ M) 등을 20 분간 각각 전처치 하였을때 현저히 감약되었으나 pirenzepine ($2{\times}10^{-6}$ M)에 의해서는 별다른 영향을 받지 않았다. $Na^+$ pump 억제제인 ouabain ($10^{-4}$ M)으로 20 분간 전처치한 후 Li-Krebs에 의한 CA 유리작용은 뚜렷이 억제되었다. 더우기 tetrodotoxin ($5{\times}10^{-7}$ M)으로 20 분간 전처치 하였을때도 Li-Krebs에 의한 CA 분비반응은 현저히 감약되었다. 이상과 같은 실험결과를 종합하여 보면, 리튬은 흰쥐 부신수질의 크롬 친화성 세포내에 측적됨으로써 칼슘의존성의 CA 분비작용을 일으키며, 이러한 분비작용은 i) 크롬친화성 세포의 탈분극과 이어서 voltage-sensitive 칼슘채널의 개방과 ii) $[Li]_i-[Ca]_0$ counter-transport system의 활성화를 통한 두가지 작용기전에 의해서 매개되는 것으로 생각된다.

• 한국식품영양과학회지
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• 제37권5호
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• pp.612-617
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• 2008

우리나라 남해안 연안에 서식하는 복섬(Takifugu niphobles) 간장의 TTX유도체들을 활성탄 칼럼을 이용하여 부분 정제하고, Hydrophilic Interaction Liquid Chromatography(HILIC)를 사용한 LC/MS(SIM mode)로 분석하였으며, pH와 가열 조건에 따른 독성 변화를 조사하고 복섬 fillet으로 복국 조리시 독성의 분포를 조사하였다. 복섬 간장의 독성분은 LC/MS에 의하여 7개의 성분이 분석되었으며, 각 성분의 함량과 조성은 5,6,11-trideoxyTTX(34.0%, 1,029.6nmol/g), 6,11-dideoxyTTX(29.3%, 887.6 nmol/g), TTX (22.1%, 667.8 nmol/g), 4,9-anhydroTTX(11.2%, 339.3nmol/g), 11-deoxyTTX＋5-deoxyTTX(2.6%, 78.6 nmol/g), 4-epiTTX(0.8%, 23.6 nmol/g), 5,6,11-trideoxyTTX(34.0%), 6,11-dideoxyTTX(29.3%), TTX(22.1%), 4,9-anhydroTTX (11.2%), 4-epiTTX(0.8%)이었다. 복섬 간장 추출물 희석액의 독성은 pH에 따라 크게 변하여 pH 3에서 8.4 MU/mL로 최고의 독성을 나타내었고, 알칼리로 갈수록 독성이 감소하여 pH 10에서는 pH 3의 1/7(1.4 MU/mL)을 나타내었다. 각각의 pH(pH 5, 7, 9)에서 $80^{\circ}C,\;100^{\circ}C,\;115^{\circ}C$를 유지하며 가열 시 온도는 높을수록, 시간은 길수록 독성은 감소하였다. 특히, 산성이나 중성에서는 독성이 완만하게 감소하는 경향을 보였으나, 알칼리 영역인 pH 9에서는 가열 10분 후에 $80^{\circ}C$의 경우라도 최초 독성(79 MU/mL)이 1/2 이하로 급격히 감소하였으며, $115^{\circ}C$에서는 완전 소멸하였다. 복섬 개체별 fillet 중의 총 독량은 $43.2{\sim}106.7$ MU로 개체에 따라서 2.5배까지 독량의 차이를 나타내었으며, 복섬 가식부에 3배량의 물을 가하여 10분간 끓일 경우 총 독량의 $64{\sim}78%$는 국물 중으로 용출되어 나와 육에 남아있는 것보다 독성이 강하였다.

• 대한약리학회지
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• 제11권2호
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• pp.29-40
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• 1975

1. 척수가토(脊髓家兎)에서 nicotine, DMPP, McN-A-343, AHR-602, tyramine, angiotensin및 neostigmine에 의한 심박증가(心搏增加)의 작용점(作用點)을 조사(調査)하였다. 2. 상기약물(上記藥物)에 의한 심박증가(心搏增加)는 reserpine 처리가토(處理家兎)에서는 대단히 약(弱)하였고, Propranolol 투여후(投與後)에는 거의 나타나지 않았다. 3. Tetrodotoxin, guanethidine은 isoproterenol, nicotine, DMPP, tyramine에 의한 심박증가(心搏增加)에는 영향(影響)을 미치지 않았으나 McN-A-343, AHR-602, angiotensin, neostigmine에 의한 심박증가(心搏增加)는 이를 현저(顯著)히 약화(弱化)시켰다. 4. Nicotine, DMPP의 심박증가(心搏增加)는 chlorisondamine으로 McN-A-343, AHR-602의 심박증가(心搏增加)는 atropine으로 각각(各各) 억제(抑制)되었다. 5. Isoproterenol, nicotine, DMPP, McN-A-343, tyramine, angiotensin, neostigmine은 적당량(適當量)을 우심방내(右心房內)에 주입(注入)하였을때 이들을 이정맥내(耳靜脈內)에 주사(注射)하였을 때와 비슷한 반응(反應)을 일으킬 수 있었다. 그러나 AHR-602 우심방내(右心房內) 주입(注入)은 유의(有意)한 심박증가(心搏增加)를 일으키지 않았다. 6. Nicotine, DMPP, neostigmine은 우심방내(右心房內) 주입시(注入時)는 현저(顯著)한 심박증가(心搏增加)를 일으켰으나, 동량(同量)을 우심실내(左心室內)에 주입(注入)하였을때는 증가(增加)를 일으키기 않았다. Isoprotereool 및 tyramine에 대한 반응(反應)은 우심실내(右心室內) 주입(注入)보다도 우심방내(右心房內) 주입시(注入時) 훨씬 컸다. 7. McN-A-343, angiotensin의 우심실내(右心室內) 주입시(注入時)는 우심방내(右心房內) 주입시(注入時)보다도 훨씬 현저(顯著)한 심박증가(心搏增加)를 일으켰고, AHR-602의 우심실내(左心室內) 주입(注入)도 현저(顯著)한 반응(反應)을 일으켰다. 8. Nicotine, DMPP, tyramine은 심장(心臟)의 aenergic nerve의 말단(末端) 또는 extraneuronal norepinephrine-store에 작용(作用)하여, Mcn-A-343, AHR-602, angiotensin은 심장(心臟)의 adrenergic nerve에 작용(作用)하여 심박증가(心搏增加)를 일으키며, nicotine, DMPP, tyramine, neostigmine의 작용점(作用點)은 주(主)로 우심방(右心房)에 McN-A-343, AHR-602, angiotenisin의 작용점(作用點)은 주(主)로 우심실(右心室)에 존재(存在)하는것으로 추론(推論)하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제1권6호
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• pp.717-730
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• 1997

$Mg^{2+}$ is the fourth most abundant cation in cellular organisms. Although the biological chemistry and the physiological roles of the magnesium ion were well known, the regulation of intracellular $Mg^{2+}$ in mammalian cells is not fully understood. More recently, however, the mechanism of $Mg^{2+}$ mobilization by hormonal stimulation has been investigated in hearts and in myocytes. In this work we have investigated the regulation mechanism responsible for the $Mg^{2+}$ mobilization induced by ${\alpha}1-adrenoceptor$ stimulation in perfused guinea pig hearts or isolated myocytes. The $Mg^{2+}$ content of the perfusate or the supernatant was measured by atomic absorbance spectrophotometry. The elimination of $Mg^{2+}$ in the medium increased the force of contraction of right ventricular papillary muscles. Phenylephrine also enhanced the force of contraction in the presence of $Mg^{2+}$-free medium. ${\alpha}1-Agonists$ such as phenylephrine were found to induce $Mg^{2+}$ efflux in both perfused hearts or myocytes. This was blocked by prazosin, a ${\alpha}1-adrenoceptor$ antagonist. $Mg^{2+}$ efflux by phenylephrine was amplified by $Na^+$ channel blockers, an increase in extracellular $Ca^{2+}$ or a decrease in extracellular $Na^+$. By contrast, the $Mg^{2+}$ influx was induced by verapamil, nifedipine, ryanodine, lidocaine or tetrodotoxin in perfused hearts, but not in myocytes. $W_7$, a $Ca^{2+}/calmodulin$ antagonist, completely blocked the pheylephrine-, A23187-, veratridine-, $Ca^{2+}-induced$ $Mg^{2+}$ efflux in perfused hearts or isolated myocytes. In addition, $Mg^{2+}$ efflux was induced by $W_7$ in myocytes but not in perfused heart. In conclusion, An increase in $Mg^{2+}$ efflux by ${\alpha}1-adrenoceptor$ stimulation in hearts can be through $IP_3$ and $Ca^{2+}-calmodulin$ dependent mechanism.