• Journal of Ginseng Research
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• 제7권2호
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• pp.148-155
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• 1983

The effects of the five ginsenosides on the activities of particulate adenylate cyclase and particulate guanylate cylase of rat brain have been studied. The range of concentrations of ginsenosides were between 10$\mu\textrm{g}$ and 500$\mu\textrm{g}$ per 500${mu}ell$ reaction mixture, Also, the effects of three ginsenosides on the activity of soluble guanylate cylace have been studied in the same range of concentrations as in particulate adenylate cyclase. Only ginsenoside Re has shown the reciprocal feeects when tested with particulated adenylate cyclase and particulate guanylated cyclase. Regulatory action of the several mononucleotides on the activities of adenylate cyclase and guanylate cyclase was examined. Ginsenoside Rd-inhibited adenylate cyclase was activated in great extent by the addition of increasing amount of GMP. On the other hand, ginsenoside Rc-activated guanylate cyclase was inhibited by the addition of increasing amount of AMP and GMP. The fact that the stimulatory action of GMP is observed only with particulated adenylate cyclase but not with soluble suanylate cyclase suggests that the action is membrane-related one. The competitive action was observed between ginsenoside Rb2 and dopamine in their binding to the receptors. This result is clear-cut evidence that the ginsenoside Rb2 binds specifically to $\beta$-adrenergic receptors.

• Biomolecules & Therapeutics
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• 제13권1호
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• pp.35-40
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• 2005

This study was performed to investigate the regulatory mechanism of cerebral blood flow of adenosine A$_{2B}$ receptor agonist in the rats, and to define whether its mechanism is mediated by adenylate cyclase, guanylate cyclase and potassium channel. In pentobarbital-anesthetized, pancuronium-paralyzed and artificially ventilated male Sprague-Dawley rats, all drugs were applied topically to the cerebral cortex. Blood flow from cerebral cortex was measured using laser-Doppler flowmetry. Topical application of an adenosine A$_{2B}$ receptor agonist, 5'-N-ethylcarboxamidoadenosine (NECA; 4 umol/I) increased cerebral blood flow. This effect of NECA (4 umol/I) was not blocked by pretreatment with adenylate cyclase inhibitor, MDL-12,330 (20 umol/I). But effect of NECA (4 umol/I) was blocked by pretreatment with guanylate cyclase inhibitor, LY-83,583 (10 umol/I) and pretreatment with ATP-sensitive potassium channel inhibitor, glipizide (5 umol/I). These results suggest that adenosine A$_{2B}$ receptor increases cerebral blood flow. It seems that this action of adenosine A$_{2B}$ receptor is mediated via the activation of guanylate cyclase and ATP-sensitive potassium channel in the cerebral cortex of the rats.

• 대한약리학회지
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• 제22권2호
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• pp.128-134
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• 1986

hydrochlorothiazide의 이뇨작용과 cyclic nucleotides와의 관계를 알아보기 위해 신조직내cyclic nucleotides 함량과 adenylate cyclase 및 guanylate cyclase 활성에 대한 hydrochlorothiazide의 영향을 관찰하였다. hydrochlorothiazide를 정맥내 투여시 약물투여 후 10분과 20분 사이에서 이뇨작용이 가장 강하게 나타났으며 60분 경과시는 이뇨작용이 소실되었다. 신조직 내 CAMP 함량은 약물투여 후 5분과 15분에 유의하게 감소되었으며 60분 경과시는 대조군과 차이가 없었다. 신조직내 cGMP 함량은 hydrochlorothiazide에 의해 영향받지 않았다. 신조직의 adenylate cyclase는 hydrochlorothiazide에 의해 활성이 억제되었으며 guanylate cyclase는 영향받지 않았다. 이상의 결과는 hydrochlorothiazide의 이뇨작용에 cAMP가 어떤 관련성을 가질 것을 시사하며 cGMP는 관련성이 없는 것으로 사료된다.

• Biomolecules & Therapeutics
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• 제12권2호
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• pp.68-73
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• 2004

This study was performed to investigate the regulatory mechanism of cerebral blood How of adenosine $A_2$ receptor agonist in the rats, and to define whether its mechanism is mediated by nitric oxide (NO), adenylate cyclase and guanylate cyclase. In pentobarbital-anesthetized, pancuronium-paralyzed and artificially ventilated male Sprague-Dawley rats, all drugs were applied topically to the cerebral cortex. Blood flow from cerebal cortex was measured using laser-Doppler flowmetry. Topical application of an adenosine $A_2$ receptor agonist [5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA; 4 umol/l)] increased cerebral blood flow. This effect of CPCA (4 umol/l) was blocked by pretreatment with NO synthase inhibitor [$N^G$-nitro-L-argine methylester (L-NAME; 140 umol/l)] and adenylate cyclase inhibitor [MDL-12,330 (20 umol/l)]. But the effect of CPCA (4 umol/l) was not blocked by pretreatment with guanylate cyclase inhibitor [LY-83,583 (10 umol/l)]. These results suggest that adenosine $A_2$ receptor increases cerebral blood How. It seems that this action of adenosine $A_2$ receptor is mediated via the NO and the activation of adenylate cyclase in the cerebral cortex of the rats.

• Journal of Ginseng Research
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• 제7권2호
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• pp.95-101
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• 1983

The effect of ginsenosides on the adenylate cyclase and guanylate cyclase of rat brain has been studied. We have found that Rbl, Rc and one unknown ginsenoside (probably Ra) exerted reciprocal effects on adenylate cyclase and guanylate cyclase. This dual effect of ginsenosides leads us to speculate that some ginsenosides may act as regulatory agents and modulate the activities of these two enzyme systems.

• Biomolecules & Therapeutics
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• 제12권2호
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• pp.108-113
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• 2004

This study was performed to investigate the regulatory mechanism of cerebral blood flow of adenosine $A_{2B}$ receptor agonist in the rats, and to define whether its mechanism is mediated by adenylate cyclase and guanylate cyclase. in pentobarbital-anesthetized, pentobrabital-paralyzed and artificially ventilated male Sprague-Dawley rats, all drugs were applied topically to the cerebral cortex. Blood How from cerebral cortex was measured using laser-Doppler flowmetry. Topical application of an adenosine $A_{2B}$ receptor agonist, 5'-N-ethylcar-boxamidoadenosine (NECA; 4 umol/l) increased cerebral blood flow. This effect of NECA (4 umol/l) was not blocked by pretreatment with adenylate cyclase inhibitor, MDL-12330 (20 umol/l). But effect of NECA (4 umol/l) was blocked by pretreatment with guanylate cyclase inhibitor, LY-83383 (10 umol/l). These results suggest that adenosine $A_{2B}$ receptor increases cerebral blood flow. It seems that this action of adenosine $A_{2B}$ receptor is mediated via the activation of guanylate cyclase in the cerebral cortex of the rats.

• Clinical and Experimental Reproductive Medicine
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• 제32권2호
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• pp.101-111
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• 2005

배 경: Pituitary adenylate cyclase-activating polypeptide (PACAP)은 양의 시상하부에서 추출된 신경펩타이드 호르몬으로 난소에도 존재하여 배양된 과립막 세포에서 스테로이드합성과 cyclic AMP 형성을 촉진함이 보고되었다. 목 적: 흰쥐 난소를 실험 모델로 사용하여 배란시 황체화호르몬 (luteinizing hormone; LH)에 의해 유도된 PACAP과 PACAP 수용체의 유전자 발현양상과 신호 전달경로를 규명하고자 하였다. 재료 및 방법: 미성숙 흰쥐의 배란전 난포를 체외 배양하면서 LH로 처리하고 PACAP 및 PACAP수용체의 유전자 발현을 보기 위해서는 Northern blot 분석과 in situ hybridization (ISH)을, 그리고 단백질 수준의 PACAP 검색을 위해서는 enzyme linked immunosorbent assay (ELISA) 분석을 이용하였다. 결 과: LH 처리 후 Northern blot상의 PACAP 유전자 발현은 6~9시간에 일시적으로 최고치에 도달하였으며 ISH로 보아 과립막 세포에서 발현됨을 알 수 있었다. ELISA 분석 상 PACAP 단백질도 LH처리 후 6~12시간에 최고치를 나타내었으며, PACAP 수용체 mRNA 역시 3~9시간에 최고치로 과립막 세포에서 발현되었다. Adenylate cyclase (AC) 억제제인 MDL12330A 처리시 LH로 발현된 PACAP mRNA가 감소되며, AC의 활성제인 forskolin 처리에는 LH시와 유사한 PACAP mRNA의 발현양상을 나타내었다. 그러나 protein kinase C (PKC)의 억제제인 chelerythrine과 2-0-tetradecanolphorbol-13-acetate (TPA) 처리로는 PACAP 의 유전자 발현에 영향을 주지 못하였다. 5-lipoxygenase의 억제제인 MK886이나 nordihydroguaiaretic acid (NDGA)로 처리한 결과 LH로 유도된 PACAP 유전자의 발현이 감소되었으나, cyclooxygenase의 억제제인 indomethacin은 별로 영향을 주지 못하였다. MEK와 p38의 억제제인 PD98059와 SB203580도 LH로 촉진 된 PACAP의 유전자 발현을 농도 의존적으로 억제하였다. 결 론 : 배란전 난포에서 PACAP과 PACAP 수용체의 유전자 발현은 모두 LH의 폭발적 분비에 의해 유도되어 일시적으로 과립막 세포에서 나타나 배란을 위한 국소적인 조절 작용을 할 것으로 추정되며, LH로 촉진된 PACAP 유전자 발현을 위한 신호전달은 cAMP-PKA, lipoxygenase 및 MAP kinase 경로를 통하는 것으로 사료된다.

• BMB Reports
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• 제47권7호
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• pp.369-375
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• 2014

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic bioactive peptide that was first isolated from an ovine hypothalamus in 1989. PACAP belongs to the secretin/glucagon/vasoactive intestinal polypeptide (VIP) superfamily. PACAP is widely distributed in the central and peripheral nervous systems and acts as a neurotransmitter, neuromodulator, and neurotrophic factor via three major receptors (PAC1, VPAC1, and VPAC2). Recent studies have shown a neuroprotective role of PACAP using in vitro and in vivo models. In this review, we briefly summarize the current findings on the neurotrophic and neuroprotective effects of PACAP in different brain injury models, such as cerebral ischemia, Parkinson's disease (PD), and Alzheimer's disease (AD). This review will provide information for the future development of therapeutic strategies in treatment of these neurodegenerative diseases.

• Journal of Plant Biology
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• 제27권1호
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• pp.7-13
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• 1984

Activities of corn endosperm adenylate cyclase and phosphodiesterase were found right after germination, and phosphodiesterase activity was shown to increase steadily. Protease activity was also found. Corn peptide fraction purified by using Sephadex G-25 column was shown to enhance corn phosphodiesterase activity buy inhibit bovine phosphodiesterase activity. And the fraction inhibits corn adenylate cyclase activity. Trypsintreated peptide fraction was shown to enhance phosphodiesterase activity 80% compared to that of native peptide fraction. However, in case of DNase phosphodiesterase was shown to be innocuous. According to cumulative results, it is more likely that peptide fraction produced by protease inhibits adenylate cyclase activity and enhance phosphodiesterase, decreasing cAMP level.

• 한국동물학회지
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• 제29권3호
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• pp.181-189
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• 1986

본 연구는 adenylate cyclase의 촉진제인 forskolin과 cholera toxin이 생쥐난자의 핵막붕괴 및 cAMP 합성에 미치는 영향을 조사하고자 수행되었다. 체외난자 배양방법과 adenylate cyclase assay 방법을 이용한 연구의 결과는 아래와 같다. 생쥐난자를 4시간 배양한 결과 대조군의 핵막붕괴율은 93%인데 반해서 forskolin (20-40$\\mu$g/ml)이 함유된 배양액에서 배양한 난자의 핵막붕괴율은 56-36%로써, forskolin의 농도에 비례하여 생쥐난자의 핵막붕괴가 현저하게 억제되었다. Forskolin (80 $\\mu$g/ml)을 3시간 처리한 후, 난자를 forskolin이 제거된 배양액으로 옮겼을 때 난자의 핵막붕괴율이 대조군과 비슷한 정도를 나타내고 있어 forskolin에 의한 핵막붕괴 억제현상은 가역적이었다. 한편, cholera toxin (10-1,000 ng/ml)은 생쥐난자의 핵막붕괴를 억제시키지 못했다. Forskolin (10-80 $\\mu$g/ml)을 생쥐난자 추출물에 첨가할 경우 cAMP합성이 5-18배 증가되었으나, cholera toxin (10-1,000 ng/ml)은 효과가 없었다. 덧붙여, adenylate cyclase의 regulatory unit의 촉진제인 guanidylimido-diphosphate (100$\\mu$M)를 forskolin과 함께 처리하여도 forskolin만 처리한 실험군에 비하여 cAMP합성정도에 변화가 없었다. 또한, cholera toxin과 guanidylimido-diphosphate(100$\\mu$M)를 함께 처리하여도 생쥐난자의 cAMP합성은 증가되지 않았다. 이상의 결과에서 forskolin에 의한 생쥐난자의 핵막붕괴 억제 현상은 난자내의 cAMP농도가 높아짐으로써 야기된 것이라 추측되며, 난자내의 cAMP 농도의 변화가 생쥐난자 성숙에 중요한 역할을 수행할 것이라고 사료된다.