Adrenal gland
A number of endocrine diseases involve dysfunctions of the adrenal gland. Overproduction of cortisol leads to Cushing's syndrome, whereas insufficient production is associated with Addison's disease. Congenital adrenal hyperplasia is a genetic disease produced by dysregulation of endocrine control mechanisms. A variety of tumors can arise from adrenal tissue and are commonly found in medical imaging when searching for other diseases.
The adrenal glands are located on both sides of the body in the retroperitoneum, above and slightly medial to the kidneys. In humans, the right adrenal gland is pyramidal in shape, whereas the left is semilunar or crescent shaped and somewhat larger. The adrenal glands measure approximately 3 cm in width, 5.0 cm in length, and up to 1.0 cm in thickness. Their combined weight in an adult human ranges from 7 to 10 grams. The glands are yellowish in colour.
Androstenedione
Androstenedione is produced in the adrenal glands and the gonads. The production of adrenal androstenedione is governed by adrenocorticotrophic hormone (ACTH), whereas production of gonadal androstenedione is under control by the gonadotropins. In premenopausal women, the adrenal glands and ovaries each produce about half of the total androstenedione (about 3 mg/day). After menopause, androstenedione production is about halved, due primarily to the reduction of the steroid secreted by the ovary. Nevertheless, androstenedione is the principal steroid produced by the postmenopausal ovary.