ABSTRACT
Following a brief review of lung structure this chapter describes the fetal and postnatal development and growth of the capillary system of the gas exchange apparatus. Because it is not possible to understand the vascular events without knowing the underlying structure, it also presents the key feature of lung development in general. The chapter ends with discussing angiogenesis during growth of the lung and describes the concept of intussusceptive microvascular growth (IMG). This form of angiogenesis has been analyzed for the first time in the lung (Caduff et al., 1986; Burri and Tarek, 1990), but seems to be a widely occuring phenomenon probably inherent to all capillary networks of vertebrate species.
