SKIN INNERVATION

The skin is richly innervated by sensory nerve fibers vegetative fibers and profusely branching through the layers of the dermis (dermal nerve plexus). The sensory fibers (afferent) are part of the and cutaneous nerves are peripheral extensions of the sensory neurons of the dorsal root ganglia or some cranial ganglia. These fibers originate from receivers skin as free nerve endings or specific sensory corpuscles. Reflect the sensibility General skin (pressure, touch, pain, temperature). also they originate, by nerve endings free, in hair follicles and blood vessels. The fibers of the hair follicle and run along the surface inside pods covering the hair root and contact with it on certain points. Vegetative fibers are postganglionic sympathetic. They come from the chain ganglia latero vertebral and reach the skin with cutaneous nerves or surrounding the cutaneous arteries. Innervate blood vessels, glands sweat and erector muscles of hairs. In the nerve terminal norepinephrine is released, except in the case of the sweat glands, where neurotransmitter is acetylcholine. The sebaceous glands They are not innervated; its activity is regulated by hormones androgenic, especially di hydro testosterone.