Endocrine gland
The adrenal glands are located above the kidneys in humans and in front of the kidneys in other animals. The adrenal glands produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. It controls the behaviour during crisis and emotional situations. It stimulates the heart and its conducting tissues and metabolic processes.
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.