Pericytes, which are seen in the capillary bed are:

Pericytes are closely associated with capillaries. It is most commonly found at the venous end of capillary bed, and also extend onto the post capillary venules. They can differentiate into smooth muscle cells during blood vessel growth and during repair after injury to a vessel. They also act as contractile cells and can affect blood flow through the capillary. Pericytes have histologic characteristics of both smooth muscle cells and endothelial cells. Ref: NMS Histology, 3e, Page 179