The roleof the catecholaminergic…
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Figure 8. Effect of TH on anterior-‐posterior heart tube patterning and specification of
chambers.
Effect of THgain-‐of-‐functionon sino-‐atrial gene expression. Embryos fromstages 10or
12 underwent in situ hybridization for the indicated genemarkers, AMHC1 and Tbx5. The control
non-‐electroporated embryos are compared with embryos electroporated with either the control
construct (pCAGs-‐I-‐GFP) or with the
th
expressing construct (pCAGs-‐TH-‐I-‐GFP). The anterior
expanded expression of AMHC1 and Tbx5 in the heart tube is indicated by the black arrows.
Visualization of GFP expression for the embryos electroporated is shown in the corresponding left
panels. (Modified from[13]).
It isworthmentioning that the th global knockoutmice, generated in 1995
by the group of Dr. Palmiter (21), is embryonic lethal starting at day E11.5-‐12.5.
Although, thenullmicedie fromapparent heart failure, adetailedcharacterization
of the mouse embryo phenotype in organogenesis has not been carried out yet.
This type of study would be required to unravel the role of catecholamines in
mousecardiogenesis.
