Though our study clearly points to a role for Prdm1 in the different stages of chicken myogenesis, our study was limited and much Topiramate remains to be determined before a complete comparison across evolution can be contemplated. For example, it remains to be determined if myogenesis in E4 and E12 limb cultures or in ovo is affected by Prdm1 knockdown, but these experiments were beyond our resources at this time. Also, the expression pattern of Prdm1 in developing chicken limbs needs to be studied Harmine-hydrochloride throughout development to determine if Prdm1 becomes limited to posterior limb bud regions as found in the mouse embryo and suggested by the previous in situ hybridization study in chicken embryos. Experiments are also needed to determine in which of the somitic, embryonic, and fetal myoblasts and myotubes or regions within the developing somites and limbs that Prdm1 expression is dependent on Hedgehog family signaling. In summary, we provide evidence that in chicken myogenic cell cultures, Prdm1 was expressed in most Pax7-positive myoblasts and in all differentiated muscle cells, irrespective of the developmental stage of cell donor or the pattern of fast and slow myosin heavy chains expressed in the differentiated cells that were formed. Thus, Prdm1 was expressed in chicken myogenic cells prior to terminal differentiation and, after differentiation, Prdm1 expression was not limited to cells that expressed slow myosin heavy chain isoforms. In addition, Prdm1 appeared to be required for differentiation of the somitic myocytes, which are the earliest myocytes to form in the avian embryo. In contrast to zebrafish, where expression of Prdm1 is limited to a subset of slow MyHCexpressing cells that originate from adaxial somite cells, Prdm1 expression in the chicken embryo and cultured myogenic cells was much more widespread. Thus, Prdm1 is likely required at more stages of myogenesis in avian than in fish embryos. Perioperative myocardial infarction, as the most common cause of serious complications, occurs in 3% to 21% of patients undergoing surgery for coronary heart disease, leads to great postoperative morbidity and mortality and results in a considerable impact on the length and cost of hospitalization.