This system provides nourishment to the dermis and by diffusion to the epidermis, which is avascular. The vascular system functions in thermoregulation. Blow flow is controlled by contraction of arterioles and venules to send blood through the capillary bed for heat radiation. In some regions of skin, arteriovenous anastomoses, or shunts, can send blood directly from the arterioles to venules in order to reduce heat loss. The dermis contains neuronal elements for touch, pain, itch, and temperature reception.
Some receptors are free nerve endings.
Other nerve endings associate with Merkel cells in the epidermis. Meissner s corpuscles reside in the dermal papillae and function as mechanoreceptors in touch perception. The hypodermis is composed of loose connective tissue with large numbers of adipose cells . The hypodermis provides insulation, shock absorption, energy storage, and the ability of skin to slide over joints. It also contains the major blood vessels of the skin.