Embryogenesis reveals the role of the “second brain” in digestion

Two muscles in the gut move along and mix together ingested food, and in between them is an autonomous network of neurons known as “the second brain”. By studying the development of digestion-related movement in chicken embyros, a team of researchers from the CNRS and the Université de Paris1 have discovered how neurons control the muscular contractions involved in digestion2 . The first movements in an intestine are purely muscular, but researchers discovered that once activated, the intestinal nervous system coordinates these two muscles: when the first one contracts to push food through the gut, neurons, deformed by this movement, order the second muscle to relax, thus opening the passage. Studying these reflexes at the embryonic stage provides further insight into how these organs function and can be affected by illness.    

• 1The team is composed of scientists from the Laboratoire Matière et Systèmes Complexes (CNRS/Université Paris Diderot) and the Institut Jacques Monod (CNRS/Université de Paris).
• 2Together, this series of movements form what is known as the peristaltic reflex.