Signals regulating the balance between proliferation and differentiation in the second heart field

摘要

The heart originates from two distinct cardiac progenitor cell populations. One, derived from anterior splanchnic mesoderm, differentiates early and gives rise to the cardiac crescent, early heart tube and ultimately the left ventricle. The second heart field (SHF), defined by differentiation delay and continued proliferation, lies in medial pharyngeal mesoderm contiguous with the cardiac crescent. Cells from the SHF contribute progressively to growth of the heart tube by the addition of cells at both poles of the heart. The SHF contributes to a major part of the definitive heart, in particular the outflow tract, the right ventricle and part of the atria (Figure 1A).