Caspase Proteins

The expression of each caspase is differentially regulated during the development and aging of the brain. One of the most studied was caspase-3, a typical pro-apoptotic executioner protease. A profound downregulation of caspase-3 transcription has been reported between postnatal day 1 (P1) and 12 (P12) (de Bilbao et al., 1999). Developmental regulation of pro-caspase-3 translation has also been reported with high and low or even undetectable levels in the newborn and adult brain, respectively (Krajewska et al., 1997; Ni et al., 1997; Hu et al., 2000). Caspase-3 expression displays an inverse correlation with cytochrome c, as demonstrated in the rat brain (Blomgren et al., 2001; Zhu et al., 2003). It has also recently been demonstrated that procaspase-3 in the neonatal P7 rat cortex exists as a complex of molecular weight of 170 kDa (Kurosu et al., 2004). Caspase-7, -8, and -10 are also highly expressed during embryonic and early postnatal development, but are downregulated after birth (Hu et al., 2000; Shimohama et al., 2001; Yakovlev et al., 2001; Kurosu et al., 2004). Naturally occurring cell death in the development rat cerebral cortex, which increases during the first postnatal week and decreases thereafter, disappearing by the end of the first month, displays the characteristic of apoptosis and is associated with endonuclease activation (Ferrer et al., 1994a). During this process, neurons expressing caspase-3, -7, -8, and -10 may determine whether a neuron dies or survives. In contrast, cytosolic caspase-2, -6, -9, and Apaf-1 are maintained at a high level postnatally in the brain, and both caspase-9 and Apaf-1 are constitutively expressed in the rat brain from E19 to 96 weeks of age (Shimohama et al., 2001). Although the mechanism remains unknown, continued expression of caspase-2, -6, -9, and Apaf-1 after the downregulation of caspase-3, -7, -8, and -10 may require the maintenance of cell homeostasis during development and aging.

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Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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