Pharmacological basis for the use of turmeric in gastrointestinal and respiratory disorders.
This study was carried out to provide scientific basis for the medicinal use of turmeric (Curcuma longa) in gastrointestinal and respiratory disorders. The crude extract of turmeric (Cl.Cr), relaxed the spontaneous and K+ (80 mM)-induced contractions in isolated rabbit jejunum as well as shifted the CaCl2 concentration-response curves. In rabbit tracheal preparation, Cl.Cr inhibited carbachol and K(+)-induced contractions. In anesthetized rats, Cl.Cr produced variable responses on blood pressure with a mixture of weak hypertensive and hypotensive actions. In rabbit aorta, Cl.Cr caused a weak vasoconstrictor and a vasodilator effect on K+ and phenylephrine-induced contractions. In guinea-pig atria, Cl.Cr inhibited spontaneous rate and force of contractions at 14-24 times higher concentrations. Activity directed fractionation revealed that the vasodilator and vasoconstrictor activities are widely distributed in the plant with no clear separation into the polar or non-polar fractions. When used for comparison, both curcumin and verapamil caused similar inhibitory effects in all smooth muscle preparations with relatively more effect against K(+)-induced contractions and that both were devoid of any vasoconstrictor effect and curcumin had no effect on atria. These data suggest that the inhibitory effects of Cl.Cr are mediated primarily through calcium channel blockade, though additional mechanism cannot be ruled out and this study forms the basis for the traditional use of turmeric in hyperactive states of the gut and airways. Furthermore, curcumin, the main active principle, does not share all effects of turmeric.
Gilani
Anwarul Hassan
AH
Department of Biological and Biomedical Sciences, The Aga Khan University Medical College, Karachi-74800, Sindh, Pakistan. anwar.gilani@aku.edu
Shah
Abdul Jabbar
AJ
Ghayur
Muhammad Nabeel
MN
Majeed
Kashif
K
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D005591:Chemical Fractionation; D030024:Curcuma / Q000737:chemistry*; D003474:Curcumin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005767:Gastrointestinal Diseases / Q000188:drug therapy*; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects; D007583:Jejunum / Q000187:drug effects; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D012140:Respiratory Tract Diseases / Q000188:drug therapy*; D014132:Trachea / Q000187:drug effects; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
D010936:Plant Extracts; D003474:Curcumin