摘要: Endocrinology is the study of structure and function endocrine glands their secretory products (hormones), including consequences excessive or deficient production latter. Hormones as primary chemical messengers that deliver information signal to a selected site target cell by virtue presence in latter highly specific receptor which hormone will bind. As result hormone-receptor interactions, sequence events initiated, often mediated second third messengers, end determined both nature type resides. Phenomena ranging from ion transport across plasma membrane modification genome transcription may be affected action. Hormone release synthesis metabolism are subject elaborate positive negative feedback controls. Thus, under normal circumstances, entire hormonal network operates integrated harmonious fashion insure growth, development maintenance dynamic steady state.