An. Real. Acad. Farm. vol 80 nº 2 2014 - page 113

The roleof the catecholaminergic…
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Figure 3. The chick and the human embryos at early stages of cardiogenesis. The chick
embryo reaches the stage15 ([16]) at~2.5days of incubation. Theheart tube is already tu rnedand
specified in auricular and ventricular regions. The human embryo reaches the stage 12(Carnigie
classification,http://php.med.unsw.edu.au/embryology/index.php?title=Carnegie_Stages)at 26-­‐30
days of pregnancy. The heart prominence is indicated by the arrow. Note the great similarity of
bothembryosat these stages.
The chimeric transcripts containingexons fromthand ins genes give rise to
two novel isoforms of the TH protein (TH-­‐INS1 and 2) with markedly reduced
functionality, when compared to the canonical TH. The levels of L-­‐DOPA in cells
expressing TH-­‐INS1 are approximately 5-­‐fold lower than those found in cells
expressing similar or lower amounts of THprotein (Figure2). Inaddition, theTH-­‐