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Vasorelaxant effect of Prunus yedoensis bark.

Lee K, Ham I, Yang G, Lee M, Bu Y, Kim H, Choi HY - BMC Complement Altern Med (2013)

Bottom Line: However, the vasorelaxant effects of MEPY on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings.The vasorelaxant effects of MEPY on endothelium-intact aortic rings were reduced by pre-treatment with L-NAME, methylene blue, or ODQ.Our results suggest that MEPY exerts its vasorelaxant effects via the activation of NO formation by means of L-Arg and NO-cGMP pathways and via the blockage of extracellular Ca(2+) channels.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Herbology, College of Korean Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, 130-701 Seoul, Republic of Korea.

ABSTRACT

Background: Prunus yedoensis Matsum. is used as traditional medicine-'Yaeng-Pi' or 'Hua-Pi'-in Japan and Korea. However, no studies have examined the pharmacological activities of the P. yedoensis bark. Only the antioxidant and antiviral activities of P. yedoensis fruit and the anti-hyperglycaemic effect of P. yedoensis leaf have been investigated. While studying the antihypertensive effects of several medicinal plants, we found that a methanol extract of P. yedoensis bark (MEPY) had distinct vasorelaxant effects on rat aortic rings.

Methods: The aortic rings were removed from Sprague-Dawley rats and suspended in organ chambers containing 10 ml Krebs-Henseleit solution. The aortic rings were placed between 2 tungsten stirrups and connected to an isometric force transducer. Changes in tension were recorded via isometric transducers connected to a data acquisition system.

Results: MEPY relaxed the contraction induced by phenylephrine (PE) both in endothelium-intact and endothelium-denuded aortic rings concentration dependently. However, the vasorelaxant effects of MEPY on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings. The vasorelaxant effects of MEPY on endothelium-intact aortic rings were reduced by pre-treatment with L-NAME, methylene blue, or ODQ. However, pre-treatment with indomethacin, atropine, glibenclamide, tetraethylammonium, or 4-aminopyridine had no affection. In addition, MEPY inhibited the contraction induced by extracellular Ca(2+) in endothelium-denuded rat thoracic aorta rings pre-contracted by PE (1 μM) or KCl (60 mM) in Ca(2+)-free solution.

Conclusions: Our results suggest that MEPY exerts its vasorelaxant effects via the activation of NO formation by means of L-Arg and NO-cGMP pathways and via the blockage of extracellular Ca(2+) channels.

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Inhibitory effect of MEPY (200 μg/ml) on the contraction induced by extracellular Ca 2+addition (0.3–10 mM) in endothelium-denuded rat aortic rings pre-contracted by phenylephrine (PE, 1 μM) (A) or KCl (60 mM) (B) in Ca2+-free Krebs-Henseleit solution. Values are expressed as mean ± SEM (n = 5–7). *P < 0.05, **P < 0.01 vs. control.
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Figure 5: Inhibitory effect of MEPY (200 μg/ml) on the contraction induced by extracellular Ca 2+addition (0.3–10 mM) in endothelium-denuded rat aortic rings pre-contracted by phenylephrine (PE, 1 μM) (A) or KCl (60 mM) (B) in Ca2+-free Krebs-Henseleit solution. Values are expressed as mean ± SEM (n = 5–7). *P < 0.05, **P < 0.01 vs. control.

Mentions: In Ca2+-free K–H solution, the cumulative addition of CaCl2 (0.3–10 mM) induced progressively increased tension in the rat aortic rings pre-contracted by PE (1 μM; Figure5A) or KCl (60 mM; Figure5B) treatment. As shown in Figure5, MEPY (200 μg/ml) pre-incubation for 20 min significantly inhibited the contraction induced by extracellular CaCl2.


Vasorelaxant effect of Prunus yedoensis bark.

Lee K, Ham I, Yang G, Lee M, Bu Y, Kim H, Choi HY - BMC Complement Altern Med (2013)

Inhibitory effect of MEPY (200 μg/ml) on the contraction induced by extracellular Ca 2+addition (0.3–10 mM) in endothelium-denuded rat aortic rings pre-contracted by phenylephrine (PE, 1 μM) (A) or KCl (60 mM) (B) in Ca2+-free Krebs-Henseleit solution. Values are expressed as mean ± SEM (n = 5–7). *P < 0.05, **P < 0.01 vs. control.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3585796&req=5

Figure 5: Inhibitory effect of MEPY (200 μg/ml) on the contraction induced by extracellular Ca 2+addition (0.3–10 mM) in endothelium-denuded rat aortic rings pre-contracted by phenylephrine (PE, 1 μM) (A) or KCl (60 mM) (B) in Ca2+-free Krebs-Henseleit solution. Values are expressed as mean ± SEM (n = 5–7). *P < 0.05, **P < 0.01 vs. control.
Mentions: In Ca2+-free K–H solution, the cumulative addition of CaCl2 (0.3–10 mM) induced progressively increased tension in the rat aortic rings pre-contracted by PE (1 μM; Figure5A) or KCl (60 mM; Figure5B) treatment. As shown in Figure5, MEPY (200 μg/ml) pre-incubation for 20 min significantly inhibited the contraction induced by extracellular CaCl2.

Bottom Line: However, the vasorelaxant effects of MEPY on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings.The vasorelaxant effects of MEPY on endothelium-intact aortic rings were reduced by pre-treatment with L-NAME, methylene blue, or ODQ.Our results suggest that MEPY exerts its vasorelaxant effects via the activation of NO formation by means of L-Arg and NO-cGMP pathways and via the blockage of extracellular Ca(2+) channels.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Herbology, College of Korean Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, 130-701 Seoul, Republic of Korea.

ABSTRACT

Background: Prunus yedoensis Matsum. is used as traditional medicine-'Yaeng-Pi' or 'Hua-Pi'-in Japan and Korea. However, no studies have examined the pharmacological activities of the P. yedoensis bark. Only the antioxidant and antiviral activities of P. yedoensis fruit and the anti-hyperglycaemic effect of P. yedoensis leaf have been investigated. While studying the antihypertensive effects of several medicinal plants, we found that a methanol extract of P. yedoensis bark (MEPY) had distinct vasorelaxant effects on rat aortic rings.

Methods: The aortic rings were removed from Sprague-Dawley rats and suspended in organ chambers containing 10 ml Krebs-Henseleit solution. The aortic rings were placed between 2 tungsten stirrups and connected to an isometric force transducer. Changes in tension were recorded via isometric transducers connected to a data acquisition system.

Results: MEPY relaxed the contraction induced by phenylephrine (PE) both in endothelium-intact and endothelium-denuded aortic rings concentration dependently. However, the vasorelaxant effects of MEPY on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings. The vasorelaxant effects of MEPY on endothelium-intact aortic rings were reduced by pre-treatment with L-NAME, methylene blue, or ODQ. However, pre-treatment with indomethacin, atropine, glibenclamide, tetraethylammonium, or 4-aminopyridine had no affection. In addition, MEPY inhibited the contraction induced by extracellular Ca(2+) in endothelium-denuded rat thoracic aorta rings pre-contracted by PE (1 μM) or KCl (60 mM) in Ca(2+)-free solution.

Conclusions: Our results suggest that MEPY exerts its vasorelaxant effects via the activation of NO formation by means of L-Arg and NO-cGMP pathways and via the blockage of extracellular Ca(2+) channels.

Show MeSH
Related in: MedlinePlus