HSL ( hormone-sensitive lipase ) is an enzyme involved in the hydrolysis of stored triglycerides and fatty acids, and is important for regulation of energy homeostasis. It has a long and a short form, generated by use of alternative translational start codons. The long form is e, Xenopus/Amphibian,pressed in steroidogenic tissues such as testis, where it converts cholesteryl esters to free cholesterol for steroid hormone production. The short form is e, Xenopus/Amphibian,pressed in adipose tissue, among others, where it hydrolyzes stored triglycerides to free fatty acids.