激素又称荷尔蒙(hormone),是内分泌细胞产生的一类具有高效能信息传递作用的化学物质。激素的种类较多而数量极微,它既非机体能量来源,又非组织或机体的结构物质,但通过传递信息,它在协调新陈代谢、生长发育等生理过程方面充当重要角色,被科学家称为“第一信使”。大多数激素分泌后直接进入血液,随血液循环到达一定的组织细胞才发挥作用。 Hormones, also known as hormones, are a class of chemicals produced by endocrine cells that have a high potency of information transfer. Hormones are many and small in number. They are neither body energy sources nor tissue or body structural substances. However, hormones play an important role in coordinating the physiological processes such as metabolism, growth and development by transmitting information and are called by scientists “First Messenger ”. Most hormone secretion directly into the blood, with the blood circulation to reach a certain amount of tissue cells only play a role.