Treasure Chest

What am I looking at?

This is a cross section through the spine of an adult zebrafish. The actin protein in the cells that make up the marrow in one of the vertebrae of the spine is shown in gold (1). The nuclei of the cells in the surrounding tissue are blue (2).

Biology in the background

Zebrafish are vertebrates – they have a bony spine containing a spinal cord. The spinal cord passes signals from the brain to the rest of the body and vice versa. Blood never actually contacts the neural cells in the spine due to a cellular blockade called the blood-spinal cord barrier. However, as you can see from the golden outlines in this image, there is an extensive network of blood and lymphatic vessels in the spinal cord that supports the neural tissue. In addition, nutrients can pass from the blood to the cerebrospinal fluid, which passes them on to the neural cells in the brain and the spinal cord.

This section of spinal cord is about 500 micrometers across, or roughly seven times larger than the width of a human hair.

Technique

This image was created using confocal microscopy.