Prevention of insulin induced airway hyper-reactivity with montelukast on isolated tracheal muscle of Guinea Pig

ABSTRACT

To explore the inhibitory effects of montelukast against insulin induced tracheal smooth muscle contraction of guinea pigs in vitro. Inhalational insulin was withdrawn from market in 2007 due to its potential to produce airway hyper-reactivity and bronchoconstriction. So we investigated the acute effects of insulin on airway reactivity and protective effects of montelukast against insulin induced airway hyper-responsiveness on isolated tracheal smooth muscle of guinea pig. Experimental study. This study was conducted in the Department of Pharmacology, Army Medical college Rawalpindi from December 2011 to June 2012. Effects of increasing concentrations of histamine [10[-8]- 10[-3] M], insulin [10[-8]- 10[-3] M] and insulin pretreated with fixed dose of montelukast [10[-5] M] were studied on isolated tracheal tissue of guinea pig. The tracheal smooth muscle contractions were recorded with Transducer on Four Channel Oscillograph. Histamine and insulin produced a concentration dependent reversible contraction of isolated tracheal muscle of guinea pig. The mean +/- SEM of maximum amplitude of contraction with histamine was 92.5 +/- 1.20 mm as compared to 35 +/- 1.13 mm in insulin treated group. The maximum amplitude of contraction achieved with insulin in the presence of montelukast was 34.5 +/- 1.024 mm. Montelukast did not significantly inhibit the contractile response of insulin on isolated tracheal muscle of guinea pig, so pretreatment of inhaled insulin with montelukast has no clinical implication in amelioration of its respiratory adverse effects such as bronchoconstriction