Home | About PR | Editorial board | Search | Ahead of print | Current Issue | Archives | Instructions | Subscribe | Advertise | Contact us |   Login 
Pharmacognosy Magazine
Search Article 
Advanced search 
Year : 2010  |  Volume : 2  |  Issue : 4  |  Page : 242-246

Vasorelaxant effect of diterpenoid lactones from Andrographis paniculata chloroform extract on rat aortic rings

1 Department of Pharmacology, School of Pharmaceutical Sciences, Universiti Sains, Malaysia; Island College of Technology, Department of Pharmacy, Sungai rusa, Balik pulau, Pulau Pinang, Malaysia
2 Department of Pharmacology, School of Pharmaceutical Sciences, Universiti Sains, Malaysia
3 Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Universiti Sains, Malaysia

Correspondence Address:
R N Sriramaneni
1003, Arlene Ct, Apt#9, Bloomington, 61701, Illinois, USA

Login to access the Email id

Source of Support: Ministry of Science, Technology and Environment of Malaysia (MOSTE) (grant no. 304/PFARMAI/640043/KI05)., Conflict of Interest: None

DOI: 10.4103/0974-8490.69125

Rights and Permissions

Background: The aim of the present study is to evaluate the possible mechanism of the vasorelaxant effect of the Andrographis paniculata chloroform extract (APCE) and diterpenoids, such as, 14-deoxyandrographolide (DA) and 14-deoxy-11, 12-didehydroandrographolide (DDA), on rat aortic rings. Methods: DA and DDA (10 μM to 40 μM) induce relaxation in the aortic rings pre-contracted with KCl (80 mM). Results: The IC 50 values are 40.47 ± 1.44 and 37.43 ± 1.41%, respectively, and this inhibition is antagonized by increasing the Ca 2+ concentration in the Kreb's medium. The results indicate that APCE, DA, and DDA may have a calcium anatgonist property. APCE, DA, and DDA also relax norepinephrene (NE)-induced sustained contractions with IC 50 values 41.63 ± 1.19, 49.22 ± 2.76, and 37.46 ± 1.41% and this relaxant effect is unaffected by the removal of the endothelium or by the presence of indomethacin and Nω-nitro-L-arginine (L-NAME). Moreover, DA and DDA inhibit the phasic and tonic contractions induced by NE in a concentration-dependent manner and show the most potent inhibition on phasic contraction (P < 0.01). Conclusion: This study shows that APCE, DA, and DDA pre-treatment presents a more potent inhibition compared to post-treatment, after the tension has reached a steady state. These results suggest that the vasorelaxation of APCE, DA, and DDA direct the inhibition of the calcium influx. The vasorelaxant effect is more active in the calcium independent pathway and more sensitive in the intial stage of contraction.

Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)

 Article Access Statistics
    PDF Downloaded86    
    Comments [Add]    
    Cited by others 1    

Recommend this journal