Investigation into the mechanism of anti-asthmatic action of Moringa oleifera.

We have studied the possible mechanism of the antiasthmatic action of Moringa oleifera seed kernel ethanolic extract (EXMO, 400 mg/kg). EXMO produced an increase in the Preconvulsion Dyspnea time induced by histamine and acetylcholine aerosol, a significant reduction in the elevated eosinophil and monocyte counts in the Broncho-Alveolar Lavage fluid of sensitized guinea pigs, reduction in the paw edema volume as compared to the control rats, and decrease in the elevated histamine release from the sensitized guinea pig lungs. The pD(2) values of histamine in tracheal chain and taenia coli were significantly greater and that in lung strip was lower in the sensitized animals and treatment with EXMO significantly decreased pD(2) values in all three preparations. Our data suggest inhibition of the immediate hypersensitive reaction, histamine release, and the infiltration of various inflammatory cells as possible antiasthmatic mechanisms of action.