The Pia Mater

Thin layer of connective tissue that entirely covers the surface of the brain and spinal cord. The pia is lined with epithelial layer towards the subarachnoid space. It is firmly bound to the nervous tissue by numerous astrocyte foot-processes. The pia mater is richly vascularized, arteries and veins enter the brain and the spinal cord from the pia. It contains numerous nerve fibers.

Nota bene! The central nervous system is protected by the skull and the vertebral column. Additional protection and support is provided by three connective tissue membranes – the meninges. Three cerebrospinal membranes are distinguished: dura mater, the thick external layer of dense connective tissue, arachnoid, a sheet of connective tissue from which a system of loosely arranged trabeculae arise resulting in the formation of a spongy subaracnoid space, and pia mater, the innermost delicate connective tissue layer, which lies directly on the surface of the brain and spinal cord.