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Table 6.1 Stages of lung development in different mammals
Stage
Species
Duration
Embryonic
Human
4–7 weeks p.c
Monkey
n.d.–E55
Sheep
E17–E30
Rabbit
n.d.–E18
Rat
E11–E13
Mouse
E9.0–E12
Pseudoglandular
Human
5–17 weeks p.c
Monkey
E55–E85
Sheep
E30–E85
Rabbit
E18–E24
Rat
E13–E18.5
Mouse
E12–E16.5
Canalicular
Human
17–26 weeks p.c
Monkey
E75-E115
Sheep
E80–E120
Rabbit
E23–E27
Rat
E18.5–E20
Mouse
E16.5–E17.5
Saccular
Human
24–38 weeks p.c
Monkey
E105–P0
Sheep
E110–E140
Rabbit
E27–E30
Rat
E21–PN4
Mouse
E17.5–PN4
Alveolar
Human
36 weeks p.c.–young adulthood
Monkey
E125–~ P180
Sheep
E120–n.d
Rabbit
E30–n.d
Rat
PN4–~ PN60
Mouse
PN5–~ PN14-21
n.d.: not determined; p.c.: post coitum; E: embryonic day; PN: postnatal day
manner. Therefore, perturbations of the developmental program lead to congenital
malformations and chronic diseases with significant morbidity and mortality.
The embryonic phase of fetal lung development (Embryonic day E9 in mice and
4–7 weeks post-conception in humans) begins with specification of respiratory progenitors in the ventral posterior foregut epithelium. These progenitors are a group of
endodermal cells expressing the NK2 homeobox 1 transcriptional factor (NKX2.1).