THE EFFECTS OF BETA-AMINOPROPIONITRILE ON THE GROWING-RAT LUNG

  • 1 January 1980
    • journal article
    • research article
    • Vol. 101  (3) , 693-+
Abstract
.beta.-Aminopropionitrile (.beta.APN), 500 ng/g body wt was injected i.p. into male rats every 2 days between 2-28 days after birth. Lungs were examined structurally and functionally and compared with lungs of control animals given injections of saline and 28 day old normal male rats which were not given injections. Lung volumes, both distended with air at 30 cm H2O and with formalin at 25 cm H2O, were increased in .beta.APN-treated animals. Architecture of lung was altered so that there was a large increase in core, or air internal to alveoli of walls of alveolar ducts and sacs. Animals given injections of .beta.APN had 40-56% fewer alveoli than those given saline injections and normal animals. Experimental animals had larger alveoli. Lungs of .beta.APN-treated animals were hypercompliant and their pressure-volume curves were shifted upward and to the left. There were morphologic changes in collagen and elastic tissue, which were more apparent in elastic tissue. Since .beta.APN interfered with synthesis of elastin and collagen, alterations in collagen-elastin network reduced alveolar multiplication in postnatal period. Control animals given saline had abnormal lungs when compared with normal animals. Their alveoli were larger and they had fewer alveoli/unit volume. The lung may be sensitive to relatively minor insults in postnatal period.