Early ontogeny of rhythm generation and control of breathing.
The ability of central networks to produce rhythmic motor behaviours linked to the respiratory function, is a remarkably conserved property of the brainstem reticular formation in vertebrates. Conserved cellular and molecular mechanisms also underlie the early embryonic development of the brainstem, leading to a segmented rhombencephalon in all vertebrates. We have proposed that the neural network that controls breathing after birth, derives from a primordial rhythmic network first active in the segmented hindbrain of the embryo. Observations on transgenic mice support this hypothesis: homozygous inactivation of Krox-20, a gene governing segmentation, leads to a lower-than-normal respiratory frequency (fR), despite fetal maturation of the respiratory network and functional compensatory control after birth.
Borday
V
V
Institut Alfred Fessard, C.N.R.S., Gif-sur-Yvette, France. borday@iaf.cnrs-gif.fr
Fortin
G
G
Champagnat
J
J
D000818:Animals; D005260:Female; D006801:Humans; D051379:Mice; D011247:Pregnancy; D015656:Respiratory Mechanics / Q000502:physiology*; D012143:Respiratory Physiological Phenomena; D012137:Respiratory System / Q000196:embryology / Q000254:growth & development*