• Title/Summary/Keyword: Guanylate cyclase

Search Result 154, Processing Time 0.025 seconds

Effect of Cuscutae Semen Extract on Blood Pressure, Regional Cerebral Blood Flow and Pial Arterial Diameter in Rats (토사자가 혈압(血壓), 국소뇌혈류량(局所腦血流量) 및 뇌연막동맥(腦軟膜動脈)에 미치는 영향(影響))

  • Kang Sung-Yong;Kim Kyung-Soo;Kim Kyong-Yoo;Lee In
    • Herbal Formula Science
    • /
    • v.6 no.1
    • /
    • pp.187-197
    • /
    • 1998
  • The study was aimed to investigate the effect cuscutae semen(CS) on the vascular systems including changes in blood pressure (BP), regional cerebral blood flow(rCBF) and pial arteriolar diameter of male Sprague-Dawely rats. The changes in rCBF were determinated by laser-Doppler flowmetry, and the changes in diameter of pial arteriole were measured through a closed crainal window. 1. Blood pressure was not affected by CS in rats. 2. rCBF was increased by CS in a dose-dependent manner. 3. Pretreatment with methylene blue(Img/kg), and propranolol(1mg/kg) significantly inhibited CS induced increased in rCBF. 4. Pretreatment with indomethacin(1mg/kg) did not inhibited CS induced increased in rCBF. 5. Pial arterial diameter was increased by CS in a dose-dependent manner. These results suggest that CS causes a diverse response of blood pressure, regional cerebral blood flow(rCBF), and pial arteral diameter. The increased in rCBF is also mediated by adrenergic ${\beta}-receptor $ and guanylate cyclase.

  • PDF

ROLE OF NITRIC OXIDE AND DISTRIBUTION OF NITRIC OXIDE SYNTHASE IN THE GUSTATORY SYSTEM (미각계에서 산화질소의 역할과 산화질소 합성효소의 분포)

  • Kim, Young-Jae;Kim, Won-Jae;Ryu, Sun-Youl
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.26 no.3
    • /
    • pp.262-269
    • /
    • 2000
  • 말초 미각계 및 중추 미각계에서 산화질소의 역할과 그것의 합성효소의 존재는 아직 규명되지 않고 있다. 본 연구는 말초미각계인혀와 미각구심성신경 그리고 중추미각계인 뇌간고속핵에서 산화질소 합성효소의 분포 및 면역조직화학 방법과 고삭신경의 extracellular recording 뇌간고속핵 절편 whole cell patch 방법으로 조사하였다. 신경성 산화질소 합성효소는 혀의 전방에 위치한 심상유두와 유곽유두에 약하게 존재하였으며 미뢰주위와 결체조직에 존재하는 신경섬유 및 혀의 상피층에 풍부하게 존재하였다. 혀에 소금물을 가하여 증가된 고삭신경의 복합전위는 산화질소 유리제인 SNP에 의해 증가되었으며 내인성 산화질소 합성효소 억제제인 L-NAME와 soluble guanylate cyclase 억제제인 ODQ에 의해 억제되었다. 문측 연수에 존재한 문측 고속핵과 진전핵에서 nNOS가 풍부하게 존재하였다. 문측 고속핵의 신경들은 안정막전위가 $-48{\pm}52mV$였고 활동전위의 크기는 $74{\pm}11mV$였다. SNP에 의해 뇌간 고속핵 신경들이 탈분극되었으며 current clamp하였을 때 활동전압의 빈도가 증가하였다. 또한 SNP에 의한 문측 고속핵의 탈분극과 활동전압 빈도증가는 L-NAME와 ODQ에 의해 감소되었다. 이상의 실험결과는 산화질소 합성효소가 혀와 뇌간고속핵에 존재하며 여기서 유리된 내인성 산화질소가 말초성 및 중추성 미각기전에 관여하리라 사료된다.

  • PDF

Carbon Monoxide as a Novel Central Pyrogenic Mediator

  • Jang, Choon-Gon;Lee, Seung-Jin;Yang, Sang-In;Kim, Jin-Hak;Sohn, Uy-Dong;Lee, Seok-Yong
    • Archives of Pharmacal Research
    • /
    • v.25 no.3
    • /
    • pp.343-348
    • /
    • 2002
  • Carbon monoxide (CO) are produced by heme oxygenase (HO), and HO was detected in hypothalamus. However, the roles of CO produced in hypothalamus was not fully elucidated. So, we tested the effects of CO on body temperature because preoptic-anterior hypothalamus was known as the presumptive primary fever-producing site. CO-saturated aCSF ($4{\;}{\mu}l$, i.c.v.) and hemin ($10{\;}{\mu}g$, i.c.v.) elicited marked febrile response. Pretreatment with indomethacin completely inhibited CO- and hemin-induced fever. Zinc protoporphyrin-IX ($10{\;}{\mu}g$, i.c.v.) or ODQ ($50{\;}{\mu}g$, i.c.v.) partially reduced hemin-induced febrile response. Dibutyryl-cGMP ($100{\;}{\mu}g$, i.c.v.) produced profound febrile response and this febrile response was attenuated by indomethacin. These results indicate that endogenous CO may have a role as a pyrogenic mediator in CNS and CO-mediated pyresis is dependent on prostaglandin production and partially on activation of soluble guanylate cyclase.

Experimental Study of Samul-tang Extract and Bambusae caulis in liquamen on the Regional Cerebral Blood Flow and Mean Arterial Blood Pressure in Normal Rats (사물탕합죽력(四物湯合竹瀝)이 국소 뇌혈류량과 평균 혈압에 미치는 실험적 연구)

  • Cho, Young-Lim;Jeong, Hyun-Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.21 no.6
    • /
    • pp.1394-1400
    • /
    • 2007
  • This study was designed to investigate the effects of Samul-tang Extract and Bambusae caulis in liquamen(SEB) on the changes in regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats. The results were as follows ; SBE significantly increased rCBF in a dose-dependent manner, and increased MABP in a dose-dependent manner. This result suggests that SBE significantly increased rCBF by dilating pial arterial diameter. Increase of SBE-induced rCBF was significantly inhibited by pretreatment with indomethacin (1 mg/kg, i.p.), an inhibitor of cyclooxygenase and increase of SBE-induced rCBF was inhibited by pretreatment with methylene blue ($10\;{\mu}g/kg$, i.p.), an inhibitor of guanylate cyclase. Increase of SBE-induced MABP was significantly increased by pretreatment with methylene blue but increase of SBE-induced MABP was decreased by pretreatment with indomethacin. These results suggested that the action of SBE was mediated by cyclooxygenase.

LIGHT DEPENDENT CHANNELS AND EXCHANGER IN THE INTERNAL LIMITING MEMBRANE OF VERTEBRATE EYE

  • Hyuk Jung;Kim, You-Young
    • Journal of Photoscience
    • /
    • v.6 no.2
    • /
    • pp.77-83
    • /
    • 1999
  • Calcium has a variety of functions in neuron and muscle cells and blood clotting, especially in the visual system where dark adapted rods cotransport with Na$\^$+/ into the cell. An influx of Ca$\^$++/ flows out of the cell through the Na$\^$+/-Ca$\^$++/ exchanger. By using a modified Using chamber in order to bring in vivo environment close, we have known that Ca$\^$++/ blocks the activity of guanylate cyclase, in consequence, having an effect on the amplitude of electroretinogram (ERG). We have measured the Ca$\^$++/, K$\^$+/, and Na$\^$+/ concentration in dark and light adapted bullfrog's (Rana catesbeiana) vitreous humor. The calcium concentration of the light adapted bullfrog's vitreous humor was higher than that of the dark adapted bullfrog's vitreous humor This means that ion activity between the photoreceptor and vitreous humor side is light dependent and we have found that a Ca$\^$++/ channel and Ca$\^$++/K$\^$+/ exchanger exist in the vitreous humor side. Taken together permeability of Ca$\^$++/, K$\^$+/ and K$\^$+/ ion internal limiting membrane faced in the vitreous humor side has light-dependent activity during the illumination.

  • PDF

Non-adrenergic non-cholinergic relaxation and contraction in circular smooth muscle of bovine reticular groove (소(우(牛)) 식도구 윤상근의 비아드레날린 비콜린성 이완 및 수축)

  • Kang, Tong-mook;Han, Ho-jae;Yang, Il-suk
    • Korean Journal of Veterinary Research
    • /
    • v.35 no.2
    • /
    • pp.279-285
    • /
    • 1995
  • To characterize non-adrenergic non-cholinergic(NANC) nerve mediated contractile responses in circular smooth muscle of bovine reticular groove, we investigated NANC relaxation and contraction induced by electric field stimulation to enteric nerves. In the presence of atropine($1{\mu}M$) and guanethidine($50{\mu}M$), electric field stimulation at frequency of 1 to 16Hz(square pulses, 0.5ms duration, 70V) evoked clear-cut relaxations through stimulations. Transient 'rebound contraction' was occured when the stimulus was switched off. All of the responses (relaxation and rebound contraction) were dose-dependently blocked by Nw-nitro-$_{\small{L}}$-arginine methyl ester(L-NAME), an inhibitor of nitric oxide synthesis, and methylene blue, and inhibitor of soluble guanylate cyclase. Tetraethyl ammonium(TEA), a potassium channel blocker, did not block the NANC relaxations.

  • PDF

Relaxant Effect of 4-Aminopyridine on the Mesenteric Artery of Rat

  • Kim, Se-Hoon;Lee, Tae-Im
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.4 no.6
    • /
    • pp.463-469
    • /
    • 2000
  • It has been well known that 4-aminopyridine (4-AP) has an excitatory effect on vascular smooth muscle due to causing membrane depolarization by blocking $K^+-channel$. However, we observed that 4-AP had an inhibitory effect on the mesenteric artery of rat. Therefore, we investigated the mechanism of 4-AP-induced vasorelaxation. The mesenteric arcuate artery and its branches were isolated and cut into ring. The ring segment was immersed in HEPES-buffered solution and its isometric tension was measured. 4-AP $(0.1{\sim}10\;mM)$ induced a concentration-dependent relaxation, which was unaffected by NO synthase inhibitor, $N^G-nitro-L-arginine$ methylester $(100\;{\mu}M)$ or soluble guanylate cyclase inhibitor, methylene blue $(100\;{\mu}M).$ Glibenclamide $(100\;{\mu}M)$, ATP-sensitive $K^+$ channel blocker, did not exert any effect on the 4-AP-induced vasorelaxation. 4-AP relaxed the sustained contraction induced by 100 mM $K^+$ or $Ca^{2+}$ ionophore, A23187 $(100\;{\mu}M)$ in a dose-dependent manner. In addition, 4-AP significantly decreased the phasic contractile response to norepinephrine in the absence of extracellular $Ca^{2+}$. However, 4-AP did not block the $^{45}Ca$ influx of rat aorta. From the above results, we suggest that 4-AP may not block the $Ca^{2+}$ influx through $Ca^{2+}-channel,$ but act as a nonspecific vasorelaxant in arterial smooth muscle.

  • PDF

Effects of LEONURI HERBA Extract on the Regional Cerebral Blood Flow and Mean Arterial Blood Pressure in Normal Rats (익모초(益母草) 추출액이 국소 뇌혈류량 및 평균혈압에 미치는 영향)

  • Bae In-Tae;Jeong Hyun-Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.19 no.6
    • /
    • pp.1599-1603
    • /
    • 2005
  • The study was designed to investigate the effects of Leonuri herba extract (LHE) on the change of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats, and further to determine the mechanism of action of LHE. The results in normal rats were as follows, LHE significantly increased rCBF in a dose-dependent manner, and MABP did not change in a dose-dependent manner. This results were suggested that LHE significantly increased rCBF by dilating pial arterial diameter. The LHE-induced increase in rCBF was significantly inhibited by Pretreatment with indomethacin(1 mg/kg, i.p.), an inhibitor of cyclooxygenase, and was significantly inhibited by methylene blue($10{\mu}g/kg$, i.p.), an inhibitor of guanylate cyclase. The LHE-induced MABP did not change by pretreatment with indomethacin but was significantly inhibited by methylene blue. This results were suggested that the mechanism of LHE was mediated by cyclooxygenase.

Pharmacological Actions of New Woohwangchungsimwon Liquid on Cardiovascular System (신우황청심원액의 심혈관계에 관한 약효연구)

  • 조태순;이선미;김낙두;허인회;안형수;박대규
    • Biomolecules & Therapeutics
    • /
    • v.5 no.4
    • /
    • pp.390-401
    • /
    • 1997
  • In order to investigate the pharmacological properties of New Woohwangchungsimwon Liquid (NCL), effects of Woohwangchungsimwon Liquid (CL) and NCL were compared. In isolated rat aorta, NCL and CL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) without regard to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxation of NCL and CL. NCL and CL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NCL and CL significantly decreased heart rate. NCL and CL, at high doses, had a negative inotropic effect that was a decrease of LVDP and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NCL and CL had no effects on parameters of action potential at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NCL and CL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between two preparations.

  • PDF

Effects of Lipopolysaccharide-Induced Heme Oxygenase and Carbon Monoxide Production on the Aortic Contractility (Lipopolysaccharide에 의한 Heme Oxygenase Induction과 Carbon Monoxide생성이 혈관수축력에 미치는 영향)

  • 장우성;손의동;이석용
    • YAKHAK HOEJI
    • /
    • v.45 no.1
    • /
    • pp.78-84
    • /
    • 2001
  • Heme oxygenase is a rate-limiting enzyme in heme catabolism that cleaves heme to form biliverdin, iron, and carbon monoxide. Heme oxygenase-1 is expressed in many types of cells and tissues and is highly induced in response to oxidative stress. Carbon monoxide, one of the products of heme oxygenase, can stimulate soluble guanylate cyclase and dilate the vascular smooth muscle. So, the induction of heme oxygenase by lipopolysaccharide (LPS)-induced oxydative stress and the effect of the resultant carbon monoxide on aortic contractility were examined in this study. Zinc protoporphyrine IX (ZnPP), a inhibitor of heme oxygenase, elicited weak contraction of thoracic aortic ring, and this effect was more potent in aorta of LPS-treated rats than control and was blocked by methylene blue. The hyperreactivity to ZnPP in LPS-treated group was blocked by co-treatment with aminoguanidine. In the aortic ring of LPS-treated rats, ZnPP didn't change the vasoreactivity to phenylephrine or acetylcholine. ZnPP elicited hyper-tensive effect in concious rats, and pretreatment with LPS did not affect this effect. Prazosin significantly diminished the hypertensive effect of ZnPP. These results indicate that LPS induced heme oxygenase in aotra, and the resultant carbon monoxide diminished the aortic reactivity to vasoconstrictor.

  • PDF