Korean J Physiol Pharmacol.  2011 Dec;15(6):339-344. 10.4196/kjpp.2011.15.6.339.

Vasorelaxing Activity of Ulmus davidiana Ethanol Extracts in Rats: Activation of Endothelial Nitric Oxide Synthase

• Cho EJ
• Park MS
• Kim SS
• Kang G
• Choi S
• Lee YR
• Chang SJ
• Lee KH
• Lee SD
• Park JB
• Jeon BH

• KMID: 2285420
• DOI: http://doi.org/10.4196/kjpp.2011.15.6.339

Abstract

Ulmus davidiana var. japonica Rehder (Urticales: Ulmaceae) (UD) is a tree widespread in northeast Asia. It is traditionally used for anticancer and anti-inflammatory therapy. The present study investigated the effect of an ethanol extract of UD on vascular tension and its underlying mechanism in rats. The dried root bark of UD was ground and extracted with 80% ethanol. The prepared UD extract was used in further analysis. The effect of UD on the cell viability, vasoreactivity and hemodynamics were investigated using propidium iodide staining in cultured cells, isometric tension recording and blood pressure analysis, respectively. Low dose of UD (10~100microg/ml) did not affect endothelial cell viability, but high dose of UD reduced cell viability. UD induced vasorelaxation in the range of 0.1~10microg/ml with an ED50 value of 2microg/ml. UD-induced vasorelaxation was completely abolished by removal of the endothelium or by pre-treatment with L-NAME, an inhibitor of nitric oxide synthase. UD inhibited calcium influx induced by phenylephrine and high K+ and also completely abolished the effect of L-NAME. Intravenous injection of UD extracts (10~100 mg/kg) decreased arterial and ventricular pressure in a dose-dependent manner. Moreover, UD extracts reduced the ventricular contractility (+dP/dt) in anesthetized rats. However, UD-induced hypotensive actions were minimized in L-NAME-treated rats. Taken together, out results showed that UD induced vasorelaxation and has antihypertensive properties, which may be due the activation of nitric oxide synthase in endothelium.

Keyword

Ulmus davidiana var. japonica; Endothelial nitric oxide synthase; Vasorelaxation; Blood pressure; Ventricular contractility

MeSH Terms

Animals
Asia
Blood Pressure
Calcium
Cell Survival
Cells, Cultured
Endothelial Cells
Endothelium
Ethanol
Hemodynamics
Injections, Intravenous
NG-Nitroarginine Methyl Ester
Nitric Oxide Synthase
Nitric Oxide Synthase Type III
Phenylephrine
Propidium
Rats
Trees
Ulmus
Vasodilation
Ventricular Pressure
Calcium
Ethanol
NG-Nitroarginine Methyl Ester
Nitric Oxide Synthase
Nitric Oxide Synthase Type III
Phenylephrine
Propidium

Figure

• 

  Fig. 1 Effect of an ethanol extract of Ulmus davidiana var. japonica (UD) on endothelial cell viability. (A) Representative endothelial cell morphology 24 h after exposure to UD (0.01~1 mg/ml). (B) Cell viability was assessed with propidium iodide staining. Each bar shows the mean±S.E. (n=4). C: untreated control, *p<0.05 versus control.

• 

  Fig. 2 Vasorelaxing effects of an ethanol extract from Ulmus davidiana var. japonica (UD) in rat aortic rings. (A) Typical tracing of the vasorelaxing effect of UD on endothelium-intact rings. UD evoked vasorelaxation in phenylephrine (300 nM) or high K+ (60 mM)-preconstricted aortic rings. Pretreatment with 0.1 mM L-nitroarginine methyl ester (L-NAME) abrogated UD-induced vasorelaxation. (B) Summarized data for the vasorelaxing effect of UD on phenylephrine-induced contraction. (C) Summarized data for the vasorelaxing effect of UD on high K+ (60 mM)-induced contraction. Vehicle: In endothelium intact rings with DMSO as a vehicle. Intact Endothelium: In endothelium intact rings. Intact endotheium+L-NAME: In endothelium-intact rings pretreated with L-NAME. Rubbed endothelium: In endothelium rubbed rings. Contraction is represented as % contraction of each maximal contraction. Data are the mean±S.E. *p<0.05 versus vehicle.

• 

  Fig. 3 Effect of an ethanol extract of Ulmus davidiana var. japonica (UD) on intracellular Ca2+ release and Ca2+ influx in rat aortic rings. Phenylephrine-induced contractions were evoked in the absence or presence of extracellular Ca2+ and high K+-induced contractions were evoked by the addition of extracellular Ca2+. Note: High K+-induced contractions were not evoked in the absence of extracellular Ca2+. The aortic rings were pretreated with UD (10µg/ml) or L-nitroarginine methyl ester (L-NAME) for 10 min before the exposure to phenylephrine or high K+. Each bar shows the mean±S.E. (n=5) *p<0.05 versus control. #p<0.05 versus UD alone.

• 

  Fig. 4 Effect of an ethanol extract of Ulmus davidiana var. japonica (UD) on hemodynamics in anesthetized rats. (A) Typical tracing for the change of arterial blood pressure for 1h after intravenous injection of UD (100 mg/kg). (B) Summarized data of the change of mean arterial pressure (B), ventricular pressure (C), heart rate (D), and ventricular contractility (E) after intravenous injection of UD (10~100 mg/kg). UD was intravenously injected into the jugular vein of rats. Data are the mean±S.E. (n=5~7). *p<0.05 versus vehicle.

• 

  Fig. 5 Effect of an ethanol extract of Ulmus davidiana var. japonica (UD) on mean arterial blood pressure in anesthetized rats. Mean arterial blood pressure which was taken in 10 min after injection of normal saline (NS), 100 mg/kg of UD (UD), L-NAME+normal saline (N-NS) and L-NAME+100 mg/kg of UD (N-UD) in anesthetized rats. UD or normal saline were intravenously injected into the jugular vein of rats. L-NAME (40 mg/kg) was injected in intraperitoneum. Data are the mean±S.E. (n=4~5). *p<0.05 for NS versus UD. #p<0.05 for NS versus N-NS.

Reference

1. Davignon J, Ganz P. Role of endothelial dysfunction in atherosclerosis. Circulation. 2004; 109(23 Suppl 1):III27–III32. PMID: 15198963.

2. Anderson TJ. Nitric oxide, atherosclerosis and the clinical relevance of endothelial dysfunction. Heart Fail Rev. 2003; 8:71–86. PMID: 12652161.

3. Kim DD, Sánchez FA, Durán RG, Kanetaka T, Durán WN. Endothelial nitric oxide synthase is a molecular vascular target for the Chinese herb Danshen in hypertension. Am J Physiol Heart Circ Physiol. 2007; 292:H2131–H2137. PMID: 17172272.

4. Jun CD, Pae HO, Kim YC, Jeong SJ, Yoo JC, Lee EJ, Choi BM, Chae SW, Park RK, Chung HT. Inhibition of nitric oxide synthesis by butanol fraction of the methanol extract of Ulmus davidiana in murine macrophages. J Ethnopharmacol. 1998; 62:129–135. PMID: 9741885.

5. Shin DY, Kim HS, Min KH, Hyun SS, Kim SA, Huh H, Choi EC, Choi YH, Kim J, Choi SH, Kim WB, Suh YG. Isolation of a potent anti-MRSA sesquiterpenoid quinone from Ulmus davidiana var. japonica. Chem Pharm Bull (Tokyo). 2000; 48:1805–1806. PMID: 11086922.

6. Kim KS, Lee SD, Kim KH, Kil SY, Chung KH, Kim CH. Suppressive effects of a water extract of Ulmus davidiana Planch (Ulmaceae) on collagen-induced arthritis in mice. J Ethnopharmacol. 2005; 97:65–71. PMID: 15652277.

7. Lee GY, Jang DS, Kim J, Kim CS, Kim YS, Kim JH, Kim JS. Flavan-3-ols from Ulmus davidiana var. japonica with inhibitory activity on protein glycation. Planta Med. 2008; 74:1800–1802. PMID: 18991204.

8. Kim YC, Lee MK, Sung SH, Kim SH. Sesquiterpenes from Ulmus davidiana var. japonica with the inhibitory effects on lipopolysaccharide-induced nitric oxide production. Fitoterapia. 2007; 78:196–199. PMID: 17343992.

9. Choi SY, Lee S, Choi WH, Lee Y, Jo YO, Ha TY. Isolation and anti-inflammatory activity of Bakuchiol from Ulmus davidiana var. japonica. J Med Food. 2010; 13:1019–1023. PMID: 20553183.

10. Lee MY, Seo CS, Ha H, Jung D, Lee H, Lee NH, Lee JA, Kim JH, Lee YK, Son JK, Shin HK. Protective effects of Ulmus davidiana var. japonica against OVA-induced murine asthma model via upregulation of heme oxygenase-1. J Ethnopharmacol. 2010; 130:61–69. PMID: 20420895.

11. Jung HJ, Jeon HJ, Lim EJ, Ahn EK, Song YS, Lee S, Shin KH, Lim CJ, Park EH. Anti-angiogenic activity of the methanol extract and its fractions of Ulmus davidiana var. japonica. J Ethnopharmacol. 2007; 112:406–409. PMID: 17428629.

12. Kim HG, Song H, Yoon DH, Song BW, Park SM, Sung GH, Cho JY, Park HI, Choi S, Song WO, Hwang KC, Kim TW. Cordyceps pruinosa extracts induce apoptosis of HeLa cells by a caspase dependent pathway. J Ethnopharmacol. 2010; 128:342–351. PMID: 20138133.

13. Lee SK, Kim HS, Song YJ, Joo HK, Lee JY, Lee KH, Cho EJ, Cho CH, Park JB, Jeon BH. Alteration of p66shc is associated with endothelial dysfunction in the abdominal aortic coarctation of rats. FEBS Lett. 2008; 582:2561–2566. PMID: 18588882.

14. Jeon BH, Gupta G, Park YC, Qi B, Haile A, Khanday FA, Liu YX, Kim JM, Ozaki M, White AR, Berkowitz DE, Irani K. Apurinic/apyrimidinic endonuclease 1 regulates endothelial NO production and vascular tone. Circ Res. 2004; 95:902–910. PMID: 15472121.

15. Jeon BH, Kim CS, Park KS, Lee JW, Park JB, Kim KJ, Kim SH, Chang SJ, Nam KY. Effect of Korea red ginseng on the blood pressure in conscious hypertensive rats. Gen Pharmacol. 2000; 35:135–141. PMID: 11744235.

16. Orallo F. Regulation of cytosolic calcium levels in vascular smooth muscle. Pharmacol Ther. 1996; 69:153–171. PMID: 8783369.

17. Van Breemen C, Cauvin C, Johns A, Leijten P, Yamamoto H. Ca²⁺ regulation of vascular smooth muscle. Fed Proc. 1986; 45:2746–2751. PMID: 2429876.

18. Karaki H, Ozaki H, Hori M, Mitsui-Saito M, Amano K, Harada K, Miyamoto S, Nakazawa H, Won KJ, Sato K. Calcium movements, distribution, and functions in smooth muscle. Pharmacol Rev. 1997; 49:157–230. PMID: 9228665.

19. McGahren ED, Beach JM, Duling BR. Capillaries demonstrate changes in membrane potential in response to pharmacological stimuli. Am J Physiol. 1998; 274:H60–H65. PMID: 9458852.

20. Richards GR, Weston AH, Burnham MP, Félétou M, Vanhoutte PM, Edwards G. Suppression of K(+)-induced hyperpolarization by phenylephrine in rat mesenteric artery: relevance to studies of endothelium-derived hyperpolarizing factor. Br J Pharmacol. 2001; 134:1–5. PMID: 11522590.

21. Van Breemen C, Farinas BR, Gerba P, McNaughton ED. Excitation-contraction coupling in rabbit aorta studied by the lanthanum method for measuring cellular calcium influx. Circ Res. 1972; 30:44–54. PMID: 5007527.

22. Blatter LA, Wier WG. Nitric oxide decreases [Ca2+]i in vascular smooth muscle by inhibition of the calcium current. Cell Calcium. 1994; 15:122–131. PMID: 8149412.

23. Barouch LA, Harrison RW, Skaf MW, Rosas GO, Cappola TP, Kobeissi ZA, Hobai IA, Lemmon CA, Burnett AL, O'Rourke B, Rodriguez ER, Huang PL, Lima JA, Berkowitz DE, Hare JM. Nitric oxide regulates the heart by spatial confinement of nitric oxide synthase isoforms. Nature. 2002; 416:337–339. PMID: 11907582.

24. Son BW, Park JH, Zee OP. Catechin glycoside from ulmus davidiana. Arch Pharm Res. 1989; 12:219–222.

25. Lee MK, Kim YC. Five novel neuroprotective triterpene esters of Ulmus davidiana var. japonica. J Nat Prod. 2001; 64:328–331. PMID: 11277749.

26. Kim JP, Kim WG, Koshino H, Jung J, Yoo ID. Sesquiterpene O-naphthoquinones from the root bark of Ulmus davidiana. Phytochemistry. 1996; 43:425–430. PMID: 8862035.

27. Lee MK, Sung SH, Lee HS, Cho JH, Kim YC. Lignan and neolignan glycosides from Ulmus davidiana var. japonica. Arch Pharm Res. 2001; 24:198–201. PMID: 11440076.

28. Lorenz M, Wessler S, Follmann E, Michaelis W, Düsterhöft T, Baumann G, Stangl K, Stangl V. A constituent of green tea, epigallocatechin-3-gallate, activates endothelial nitric oxide synthase by a phosphatidylinositol-3-OH-kinase-, cAMP-dependent protein kinase-, and Akt-dependent pathway and leads to endothelial-dependent vasorelaxation. J Biol Chem. 2004; 279:6190–6195. PMID: 14645258.