Veterinary Histology and Embryology

BLOOD VESSELS AND NERVES

• From the larger arteries of the subcutaneous tissue, branches pass into the reticular layer of dermis, where they form networks.
• From this network, branches pass into the papillary, layer where they form second network. From this the papillae, hair follicles, sebaceous glands etc., are supplied.
• The primary plexuses supplies sweat gland, fat lobules etc.
• The venous capillaries form similar plexuses in the papillary layer, in the reticular layer and finally in the subcutaneous tissue, form where veins arise and accompany the arteries.
• The nerves to the skin are mainly sensory and sympathetic efferent supply to sweat glands errectores pilorum and plain muscle in the walls of blood vessels.
• The sensory nerves end in Pacinian corpuscles in the subcutaneous tissue, in tactile corpuscles of Meissner in the dermal papillae and free nerve endings among the epithelial cells in the epiedermis, pacinian corpuscles are receptors for pressure sense.
• Meissner’s corpuscles for tactile or discriminatory touch and free nerve endings for pain.