Changes of soluble and membrane proteins of rat brain during pre- and postnatal development.

Membrane and soluble protein fractions were obtained from forebrain, midbrain and hindbrain of embryos or neonatal rats. The amount of the protein of the corresponding brain parts was followed up as a function of DNA content. Age-related changes of the concentration of over 50 protein bands were observed in all three brain parts. There are also bands which tend to disappear (or appear) at distinct stages of development. In each of the brain parts there are bands showing age-dependent changes characteristic for this part. A common feature of the changes of the membrane protein patterns of forebrain and midbrain observed during development is a decrease of the concentration of proteins with lower molecular mass (below 40 kD), while proteins of higher molecular mass become better pronounced. Compared to forebrain and midbrain the hindbrain has a relatively conservative protein composition throughout development.