Adrenal gland
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which produces steroid hormones and an inner medulla. The adrenal cortex itself is divided into three zones: the zona glomerulosa, the zona fasciculata and the zona reticularis.
Adrenaline
The adrenal glands contribute about 7% of circulating norepinephrine, most of which is a spill over from neurotransmission with little activity as a hormone.
Pharmacological doses of epinephrine stimulate α, α, β, β, and β adrenoceptors of the sympathetic nervous system. Sympathetic nerve receptors are classified as adrenergic, based on their responsiveness to adrenaline.