Fatty acids are released from adipose tissue via hydrolysis of their stored triacylglycerol. This is done in a tightly regulated manner in order to properly release the fatty acids. Hydrolysis is induced through the activation of the enzyme hormone sensitive lipase (HSL). HSL is active in its phospho- form, as it is a phospho-dephsos enzyme. The phosphorylation of HSL is induced by hormones including norepinephrine, epinephrine, ACTH, and cortisol. These hormones attach to the surface of the adipocyte, and subsequently activate adenyl cyclase, stimulating a cAMP phosphorylation cascade, resulting in the phosphorylation of HSL. Following release from adipocytes, fatty acids then enter the blood attached to serum albumin in order to reach tissues including the heart, muscle, and liver where they are oxidized.