The first pass is the colour plate the inside of blood vein with blood cells and albumin floating down it.
The second pass is a small colour correction of each element and the addition of small blue molecule that is bound to the albumin.
Third pass is a lighting pass, where I used the zdepth and curves to create a more visually interesting environment. I also added an AO map to ground the scene and give it a more encased feeling inside the vein.
fourth pass provided atmosphere and depth to the shot. Here I also used the Zdepth to create this look.
The Fifth and final pass I added floaty bits to give a liquid look, some final colour correction and some motion blur.