TY - JOUR
T1 - Intestinal, airway, and cardiovascular relaxant activities of thymoquinone
AU - Ghayur, Muhammad Nabeel
AU - Gilani, Anwarul Hassan
AU - Janssen, Luke Jeffrey
PY - 2012
Y1 - 2012
N2 - Thymoquinone (TQ) is a bioactive component found in many medicinal herbs. In this study, we report the smooth and cardiac muscle relaxant activities of this compound. TQ concentration dependently suppressed spontaneously contracting rabbit jejunum while also relaxed high K+-(80 mM) induced contractions in jejunum and guinea-pig ileum, indicating activity at voltage-operated Ca++ channels (VOCC). Further, TQ displaced Ca ++ concentration-response curves, obtained in a Ca++-free environment, to the right, showing blockade of VOCC. Similar activity was observed with verapamil, a standard VOCC blocker. TQ also exhibited nonadrenergic relaxation of agonist-induced contractions in guinea-pig trachea. When tested in fluo-4-loaded mouse lung slices, TQ inhibited ACh-induced airway narrowing and Ca++ signalling in airway smooth muscle cells. In endothelium-intact and endothelium-denuded rat aorta, TQ inhibited high K +-induced contractions at significantly lower concentrations than phenylephrine-(PE-) (1 microM) induced contractions. Relaxation of PE-induced contractions was resistant to blockade by L-NAME and atropine. In guinea-pig atria, TQ showed noncholinergic relaxation of atrial force and rate of contractions. These data suggest smooth and cardiac muscle relaxant activity of TQ possibly mediated, in part, via blockade of VOCC. The results also justify the use of TQ containing plants in related health disorders like colic, diarrhoea, cough, and asthma.
AB - Thymoquinone (TQ) is a bioactive component found in many medicinal herbs. In this study, we report the smooth and cardiac muscle relaxant activities of this compound. TQ concentration dependently suppressed spontaneously contracting rabbit jejunum while also relaxed high K+-(80 mM) induced contractions in jejunum and guinea-pig ileum, indicating activity at voltage-operated Ca++ channels (VOCC). Further, TQ displaced Ca ++ concentration-response curves, obtained in a Ca++-free environment, to the right, showing blockade of VOCC. Similar activity was observed with verapamil, a standard VOCC blocker. TQ also exhibited nonadrenergic relaxation of agonist-induced contractions in guinea-pig trachea. When tested in fluo-4-loaded mouse lung slices, TQ inhibited ACh-induced airway narrowing and Ca++ signalling in airway smooth muscle cells. In endothelium-intact and endothelium-denuded rat aorta, TQ inhibited high K +-induced contractions at significantly lower concentrations than phenylephrine-(PE-) (1 microM) induced contractions. Relaxation of PE-induced contractions was resistant to blockade by L-NAME and atropine. In guinea-pig atria, TQ showed noncholinergic relaxation of atrial force and rate of contractions. These data suggest smooth and cardiac muscle relaxant activity of TQ possibly mediated, in part, via blockade of VOCC. The results also justify the use of TQ containing plants in related health disorders like colic, diarrhoea, cough, and asthma.
UR - http://www.scopus.com/inward/record.url?scp=84872149378&partnerID=8YFLogxK
U2 - 10.1155/2012/305319
DO - 10.1155/2012/305319
M3 - Article
AN - SCOPUS:84872149378
SN - 1741-427X
VL - 2012
JO - Evidence-based Complementary and Alternative Medicine
JF - Evidence-based Complementary and Alternative Medicine
M1 - 305319
ER -
