Sweat Glands

Sweat glands occur in nearly all regions of the skin, but are most numerous in the palms and soles. Each gland consists of a tiny tube that originates as a ball-shaped coil in the dermis or subcutaneous layer of the skin. The coiled portion of the gland is closed at its deep end and is lined with sweat-producing cells. Some sweat glands, the "apocrine glands," respond to emotional stress. Apocrine secretions typically have odors, and the glands are considered to be scent glands. They begin to function at puberty and are responsible for some skin regions becoming moist when a person is emotionally upset, frightened, or experiencing pain. They are also active when a person is sexually stimulated. In adults, the apocrine glands are most numerous in the armpits, groin, and in the regions around the nipples. They are usually associated with hair follicles. Other sweat glands, the "eccrine glands," are not connected to hair follicles. They function throughout life by responding to elevated body temperature due to environmental heat or physical exercise. These glands are common on the forehead, neck, and back, where they produce profuse sweating on hot days and when a person is physically active. They also are responsible for the moisture that may appear on the palms and soles when a person is emotionally stressed.