• Korean Journal of Acupuncture
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• v.20 no.4
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• pp.31-40
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• 2003

Objectives : The purpose of this study is to investigate whether Haenggan(LR2) Reduction in Acupuncture affects cerebral hemodynamics〔regional cerebral blood flow(rCBF), mean arterial blood pressure(MABP)〕in normal rats, and to make manifest whether Haenggan(LR2) Reduction in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. Methods : This experiments was to investigate at the other changes of rCBF and MABP at Haenggan(LR2) Reduction in Acupuncture in normal rats, pretreated rats with indomethacin(1 mg/kg, i.v.) and pretreated rats with methylene blue$(10\;{\,u}g/kg,\;i.v.)$. Results : 1. Haenggan(LR2) Reduction in Acupuncture was significantly increased rCBF during acupuncture and after withdrawing of the needle. 2. Haenggan(LR2) Reduction in Acupuncture was decreased MABP during acupuncture, but Haenggan(LR2) Reduction in Acupuncture was increased MABP in compared with normal condition. 3. Pretreatment with indomethacin(1 mg/kg, i.v.) was significantly inhibited Haenggan(LR2) Reduction in Acupuncture induced increase of rCBF, but was increased Haenggan(LR2) Reduction in Acupuncture induced increase of MABP. 4. Pretreatment with methylene blue$(10\;{\mu}g/kg,\;i.v.)$ was significantly decreased Haenggan(LR2) Reduction in Acupuncture induced increase of rCBF and MABP. This results suggest that Haenggan(LR2) Reduction in Acupuncture increased rCBF by dilating pial arterial diameter, and the mechanism of Haenggan(LR2) Reduction in Acupuncture is mediated by guanylate cyclase.

• Journal of Pharmacopuncture
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• v.16 no.4
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• pp.30-35
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• 2013

Objectives: This study was designed to investigate the effects of Calculus Bovis-Fel Uris-Moschus pharmacopuncture (BUM) on the regional cerebral blood flow (rCBF) and the mean arterial blood pressure (MABP) in normal and cerebral ischemic rats and to investigate a possible pathway involved in the effects of BUM. Methods: The changes in the rCBF and the MABP following BUM into Fengfu (GV16) were determined by using a laser-Doppler flow meter and a pressure transducer, respectively. Results: BUM significantly increased the rCBF and decreased the MABP in normal rats in a dose-dependent manner. The effect on the rCBF was significantly inhibited by pretreatment with methylene blue (0.01 mg/kg, intraperitoneal), an inhibitor of guanylate cyclase, but was not affected by pretreatment with indomethacin (1 mg/kg, intraperitoneal), an inhibitor of cyclooxygenase. The BUM-induced decrease of the MABP was changed neither by methylene blue nor by indomethacin pretreatment. In the cerebral ischemic rats, the rCBF was stably increased upon cerebral reperfusion in the BUM group in contrast to the rapid and marked increase in the control group. Conclusion: This study demonstrated that BUM into Fengbu (GV16) increased the rCBF in a dose-dependent manner in the normal state; furthermore, it improved the stability of the rCBF in the ischemic state upon reperfusion. Also, the effects of BUM on the rCBF were attenuated by inhibition of guanylate cyclase, suggesting that the effects involved the guanylate cyclase pathway.

• The Korean Journal of Zoology
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• v.30 no.2
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• pp.193-209
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• 1987

Patterns of amylase secretion in mouse pancreatic fragments were studied over a period of time after the tissue was stimulated by acetyicholine and MNNG. MNNG is known to activate guanylate cyclase and thus increase the cGMP concentration in the pancreatic acinar cell. These amylase secretion patterns were studied to investigate the role of cGMP in reaction cascade during secretion response of the tissues stimulated by acetyicholine. Cellular response of amylase secretion in the pancreas by acetyicholine was divided into two phases. During the first phase, zymogen granules which had existed in the cells were secreted by the action of $Ca^2$+ and calmodulin immediately after secretagogue administration, this being known as the initial response. When the tissue was stimulated by acetylcholine in a $Ca^2$+-deficient medium or one containing trifluoperazine as a calmodulin antagonist, this initial response was reduced. In the second phase, newly formed zymogen granules were secreted as sustained response after protein synthesis was triggered by secretagogue. This response was provoked by an activation of protein kinase C. When either cycloheximide as a protein synthesis inhibitor or dibucaine as a protein kinase C inhibitor were added to the incubation medium, this sustained response was remarkablely depressed in the pancreatic fragments stimulated with acetylcholine. In the pancreatic acinar cell, phosphatidylinositol turnover plays an important role in the secretion response and hexachlorocyclohexane inhibits this phosphatidylinositol turnover. The pancreatic tissue treated with the hexachlorocyclohexane exhibited inhibition on both initial and sustained responses of amylase secretion by acetylcholine. MNNG also accelerated amylase secretion from the tissue gradually along incubation time. The 22 minutes fraction of the pancratic secretion after administration of both acetylcholine and MNNG showed higher amylase activity than the neighboring fractions. Guanylate cyclase potentiated the sustained response. Even if it is experimented with an indirect method, guanylate cyclase was found responsible for activation of the sustained response of a step prior to the action of protein kinase C. As conclusion, it was considered that amylase secretion in mouse pancreatic fragments stimulated by acetylcholine is a three phasic response.

• Journal of Acupuncture Research
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• v.29 no.2
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• pp.73-88
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• 2012

Objectives : The purpose of this study is to research the effects of acupuncturing $BL_{67}$ and $LI_1$ and determine the mechanism of action of acupuncturing $BL_{67}$ and $LI_1$ by measuring the changes of regional cerebral blood flow(rCBF) and mean arterial blood pressure(MABP) in normal rats and ischemic rats. Method : This study researched the effects of acupuncturing $BL_{67}$ and $LI_1$ on the change of rCBF and MABP. To determine the mechanism of action of acupuncturing $BL_{67}$ and $LI_1$, pretreatment with indomethacine and methylene blue was done. Result : 1. Acupuncturing $BL_{67}$ and $LI_1$ significantly increased rCBF and acupuncturing $BL_{67}$ and $LI_1$ induced increase of rCBF was significantly inhibited by pretreatment with indomethacin(1 mg/kg, i.p.), an inhibitor of cyclooxygenase, and methylene blue(10 ${\mu}g$/kg, i.p.), an inhibitor of guanylate cyclase. 2. Acupuncturing $BL_{67}$ and $LI_1$ decreased MABP and there was no significantly change of decrease of MABP on acupuncturing $BL_{67}$ and $LI_1$ by pretreatment with indomethacin and methylene blue. 3. These result suggested that acupuncturing $BL_{67}$ and $LI_1$ might significantly increase rCBF by dilating arterial diameter and mechanism of acupuncturing $BL_{67}$ and $LI_1$ might be mediated by cyclooxygenase and guanylate cyclase. 4. The rCBF was significantly and stably increased by acupuncturing $BL_{67}$ and $LI_1$ during the period of cerebral reperfusion in cerebral ischemic rats, which contrasted with the rapid and marked increase in the control group. Pretreatment with methylene blue significantly decreased rCBF by acupuncturing $BL_{67}$ and $LI_1$ during the period of ischemic state, increased rCBF during the period of cerebral reperfusion. These results suggested that the mechanism of acupuncturing $BL_{67}$ and $LI_1$ might be mediated by guanylate cyclase. Conclusion : Acupuncturing $BL_{67}$ and $LI_1$ can increase rCBF in normal state, and improve stability of rCBF in ischemic state. In addition, we suggested that mechanisms related with acupuncturing $BL_{67}$ and $LI_1$ was more involved in the guanylate cyclase pathway.

• The Korean Journal of Zoology
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• v.30 no.1
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• pp.1-9
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• 1987

Cyclic AMP (cAMP) was known to play a key role in the regulation of cumulus expansion and oocyte maturation of mammalian cumulus-oocyte complexes (COC's) in vivo and in vitro. The present experiments were conducted to know how intracellular level of cAMP in these cells is controlled. Intracellular cAMP level was modulated by culturing mouse CGC's with an adenylate cyclase stimulator, forskolin, a phosphodiesterase inhibitor, 3-isobutyl-1-methyixanthine (IBMX), human chorionic gonadotrophin (HCG), or follicle stimulating hormone (FSH). The rate of cumulus expansion and germinal vesicle break-down (GVBD) was checked after culture and used as a biological end point. Forskolin in the medium began to stimulate the expansion of the complexes at 1 nM and induced maximum expansion (80~90%) at 0 1~10 $\mu$M. The expansion rate was reduced to 60% when forskolin concentration was increased to 100 $\mu$M. Oocyte GVBD occurred normally (75~82%) in the presence of 10 $\mu$M of forskolin, but partial suppression was appeared at 100 pM of the drug (40%). IBMX also stimulated the expansion from the concentration of 0.01 pM and induced full expansion (81~89%) between the concentration of 1-1000 $\mu$M. Meiotic resumption was occurred normally under 10 $\mu$M of IBMX, but suppressed drastically from the concentration of 100 $\mu$M. The minimum exposing time to hormone or drugs required to trigger cumulus expansion was two minutes with HCG, 15~30 minutes with FSH and fors kolin, and two hours with IBMX. The data presented here seemed to imply that intracellular cAMP level in cumulus cells is regulated by both adenylate cyclase and phosphodiesterase and cumulus expansion is induced by a peak of cAMP while meiotic arrest is maintained by continuous presence of cAMP.

• The Korean Journal of Pharmacology
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• v.31 no.3
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• pp.291-297
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• 1995

The objectives of this study is to compare the inhibitory mechanism of sodium nitroprusside and forskolin on the phorbol ester, activator of protein kinase C (PKC), -induced contractions in rat aorta. $0.1\;{\mu}M$ phorbol dibutyrate (PDBu) induced sustained contractions and increased phosphorylations of myosin light chain (MLC) time-dependently. At 30 min, the contractions and phosphorylations of MLC by PDBu were augmented maximally and remained constant. Moreover, $^{45}Ca^{2+}$ uptake was increased 30 min after PDBu stimulation from resting values. Sodium nitroprusside which activates guanylyl cyclase followed by increasing cGMP, inhibited the PDBu-induced contractions concentration-dependently. On the other hand, forskolin which activates adenylyl cyclase followed by increasing cAMP, also inhibited the PDBu-induced contractions concentration-dependently. However, sodium nitroprusside was more potent to inhibition of the PDBu-induced contractions than forskolin. Sodium nitroprusside inhibited $^{45}Ca^{2+}$ uptake by PDBu stimulation. Forskolin also inhibited $^{45}Ca^{2+}$ uptake by PDBu stimulation. Sodium nitroprusside and forskolin inhibited the phosphorylations of MLC by PDBu, respectively. However, sodium nitroprusside was more potent to inhibition of phosphorylations of MLC by PDBu than forskolin. From these results, Sodium nitroprusside via cGMP or forskilin via cAMP may reduce myoplasmic $Ca^{2+}$ followed by suppression of phosphorylations of MLC of PKC-mediated contractions, which results in vasodilation. However, cGMP may play a role more importantly than cAMP on the regulation of protein kinase C-mediated contraction in vascular smooth muscle.

• Development and Reproduction
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• v.2 no.1
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• pp.21-27
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• 1998

The present study was performed to analyze the gene expressions of pituitary adenylate cyclase-activating polypeptide(PACAP) and its receptor in the rat uterus, a candidate for novel extrahypothalamic source and target. The PACAP cDNA fragments corresponding to the common exon region which is found in both the rat hypothalamus and testis were produced from all tissue samples including the rat uterus by reverse transcriptionpolymerase chain reaction (RT-PCR). No PCR product was amplified from the rat hypothalamic, pituitary, ovarian and uterine samples when the 5' primer corresponding to the testis-specific exon 1 region was used, while the predicted size of product was detected from the testis sample. RT-PCR using the uterine RNA and specific primers for the PACAP receptor yielded products with predicted sizes. Transcripts for the rat uterine PACAP receptor were identified as type I isoforms with hip-hop and hip- or hop-type inserts. After pregnant mare's serum gonadotropin (15 IU) treatment of immature rats (day 25), the level of PACAP mRNA was increased in 24 h and 48 h group, and was declined to the lowest in 72 h group. The present study shows the presence of transcripts for PACAP and its receptor isoform in the rat uterus. These finding ssuggest that the uterine PACAP ight act as a novel autocrine and/or paracrine factor via its specific receptors on the reglulation of rat uterine function and physiology during the reproductive cycle.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.3
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• pp.225-231
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• 1997

As it has been reported that the depolarization-induced norepinephrine (NE) release is modulated by activation of presynaptic $A_1-adenosine$ heteroreceptor and various lines of evidence indicate the involvement of adenylate cyclase system in $A_1-adenosine$ post-receptor mechanism in hippocampus, it was attempted to delineate the role of adenylate cyclase system in the $A_1-receptor-mediated$ control of NE release in this study. Slices from rat hippocampus were equilibrated with $[^3H]-NE$ and the release of the labelled products was evoked by electrical stimulation.(3 Hz, $5Vcm^{-1}$, 2 ms, rectangular pulses). The influence of various agents on the evoked tritium-outflow was investigated. $N^6-Cyclopentyladenosine$ (CPA), a specific $A_1-adenosine$ receptor agonist, in concentrations Tanging from 0.1 to $10{\mu}M$ decreased the $[^3H]-NE$ release in a dose-dependent mauler without any change of basal rate of release. 8-Cyclopentyl-1,3-dipropylxanthine (DPCPX, $2{\mu}M$), a selective $A_1-receptor$ antagonist, inhibited the CPA effect. The responses to N-ethylmaleimide $(3&10{\mu}M)$, a SH-alkylating agent of G-protein, were characterized by increments of the evoked NE-release and the CPA effects were completely abolished by NEM pretreatment. Forskolin, a specific adenylate cyclase activator, in concentrations ranging from 0.1 to $30{\mu}M$ increased the evoked and basal rate of NE release in a dose-dependent manner and the CPA effects were inhibited by forskolin pretreatment. Rolipram $(1&10{\mu}M)$, a phosphodiesterase inhibitor, did not affect the evoked NE release but reduced the CPA effect. And 8-bromo-cAMP $(100&300{\mu}M)$, a membrane permeable cAMP analogue inhibited the CPA effect significantly. These results suggest that the $A_1-adenosine$ heteroreceptor plays an important role in NE-release via nucleotide-binding protein $G_i$ in the rat hippocampus and that the adenylate cyclase system might be participated in this process.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2003.06a
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• pp.39-46
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• 2003

• 대한생식의학회:학술대회논문집
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• 1997.11a
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• pp.80-80
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• 1997