maternal nicotine exposure-induced collagen pulmonary changes

nicotine is an alkaloid by high level of addictive property that can quickly assimilate from smoker’s lung. it passes from the placenta and gathers in the developing fetus. our previous study showed that collagen type iv plays a critical role in basement membrane of different embryonic organs. in this study the effect of maternal nicotine was evaluated by collagen iv changes in lung of mice offspring during pre and postnatal period. pregnant balb/c mice were divided into 2 experimental and 2 control groups. experimental group 1 received 3 mg/kg nicotine intrapritoneally from day 5 of gestation to last day of pregnancy. experimental group 2 received the same amount of nicotine during the same gestational days as well as 2 first week after birth. the control groups received the same volume of normal saline during the same periods. at the end of exposure times, all newborns were anesthetized and their lungs were removed and immunohistochemical study for tracing collagen was carried out. our results showed that collagen reaction in the bronchial basement membrane (bbm) and extra cellular matrix (ecm) of the lung parenchyma experienced a remarkable increase when compared to the control ones. cell necrosis definition in lung parenchyma of the experimental group 2 was the other finding that our investigation revealed. these data indicate that maternal nicotine exposure may induce a noticeable collagen increase with a reasonable amount in bbm and ecm of respiratory system of next generation.