TY - JOUR
T1 - Bronchodilatory effect of Acorus calamus (Linn.) is mediated through multiple pathways
AU - Shah, Abdul Jabbar
AU - Gilani, Anwarul Hassan
N1 - Funding Information:
This study was undertaken with partial financial support from the Pakistan Science Foundation. The plant material was gifted by Dr. Farzana Shaheen, HEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan.
PY - 2010/9
Y1 - 2010/9
N2 - Aim of the study: This study was undertaken to provide a pharmacological basis for traditional use of Acorus calamus in airways disorders. Materials and methods: Isolated guinea-pig trachea and atria were suspended in organ baths bubbled with carbogen and mechanisms were found using different parameters. Results: In isolated guinea-pig tracheal segments, crude extract of Acorus calamus was more effective than carbachol in causing relaxation of high K+ (80mM) precontractions, similar to verapamil, suggesting blockade of calcium channels. The n-hexane fraction was equipotent against both precontractions, similar to papaverine, while ethylacetate fraction was more potent against carbachol precontractions but had a negligible dilator effect against K+, similar to atropine and or rolipram. Pretreatment of tracheal preparations with n-hexane or ethylacetate fractions potentiated isoprenaline-induced inhibitory concentration-response curves, similar to papaverine or rolipram. Pretreatment of tracheal preparations with ethylacetate fraction caused a rightward parallel shift in carbachol response curve at lower concentration (0.003mg/mL) similar to atropine and a non-parallel shift at higher concentrations (0.01mg/mL), with reduction of maximum response, similar to rolipram. In isolated guinea-pig atrial preparations, crude extracts, its fractions and papaverine inhibited force and rate of contractions at higher concentrations than the smooth muscle while verapamil was equipotent. Conclusion: These data indicate the presence of unique combination of airways relaxant constituents in crude extract of Acorus calamus, a papaverine-like dual inhibitor of calcium channels and phosphodiesterase in n-hexane fraction and a novel combination of anticholinergic, rolipram-like phosphodiesterase4 inhibitor in ethylacetate fraction and associated cardiac depressant effect, provide a pharmacological basis for traditional use of Acorus calamus in disorders of airways.
AB - Aim of the study: This study was undertaken to provide a pharmacological basis for traditional use of Acorus calamus in airways disorders. Materials and methods: Isolated guinea-pig trachea and atria were suspended in organ baths bubbled with carbogen and mechanisms were found using different parameters. Results: In isolated guinea-pig tracheal segments, crude extract of Acorus calamus was more effective than carbachol in causing relaxation of high K+ (80mM) precontractions, similar to verapamil, suggesting blockade of calcium channels. The n-hexane fraction was equipotent against both precontractions, similar to papaverine, while ethylacetate fraction was more potent against carbachol precontractions but had a negligible dilator effect against K+, similar to atropine and or rolipram. Pretreatment of tracheal preparations with n-hexane or ethylacetate fractions potentiated isoprenaline-induced inhibitory concentration-response curves, similar to papaverine or rolipram. Pretreatment of tracheal preparations with ethylacetate fraction caused a rightward parallel shift in carbachol response curve at lower concentration (0.003mg/mL) similar to atropine and a non-parallel shift at higher concentrations (0.01mg/mL), with reduction of maximum response, similar to rolipram. In isolated guinea-pig atrial preparations, crude extracts, its fractions and papaverine inhibited force and rate of contractions at higher concentrations than the smooth muscle while verapamil was equipotent. Conclusion: These data indicate the presence of unique combination of airways relaxant constituents in crude extract of Acorus calamus, a papaverine-like dual inhibitor of calcium channels and phosphodiesterase in n-hexane fraction and a novel combination of anticholinergic, rolipram-like phosphodiesterase4 inhibitor in ethylacetate fraction and associated cardiac depressant effect, provide a pharmacological basis for traditional use of Acorus calamus in disorders of airways.
KW - Acorus calamus
KW - Airways disorders
KW - Anticholinergic
KW - Calcium antagonist
KW - PDEs inhibition
UR - http://www.scopus.com/inward/record.url?scp=77956267433&partnerID=8YFLogxK
U2 - 10.1016/j.jep.2010.07.024
DO - 10.1016/j.jep.2010.07.024
M3 - Article
C2 - 20643200
AN - SCOPUS:77956267433
SN - 0378-8741
VL - 131
SP - 471
EP - 477
JO - Journal of Ethnopharmacology
JF - Journal of Ethnopharmacology
IS - 2
ER -