Role of meconium and hypoxia in meconium aspiration-induced lung injury in neonatal rabbits.

Background: We previously showed that meconium causes lung cell death by apoptosis and inflammatory cytokine expression. Whether this is due to meconium exposure itself, or meconium related hypoxia remains unclear.

Objectives: To elucidate the effects of meconium, saline, milk, hypoxia and hyperoxia induced lung injury.

Inhibition of meconium-induced cytokine expression and cell apoptosis by pretreatment with captopril.

Objective: To study whether pretreatment of newborn lungs by captopril inhibits meconium-induced lung injury and inflammatory cytokine expression.

Design: Four groups of 2-week-old rabbit pups were used for the study: group 1, saline instilled rabbits; group 2, captopril-pretreated rabbits; group 3, meconium-instilled rabbits; and group 4, captopril-pretreated and then meconium-instilled rabbits. Each group was studied at different time points: 0, 2, 4, 8, and 24 hours after instillation of meconium.