NURS 220 Lecture Notes - Lecture 26: Parathyroid Gland, Endocrine Gland, Pineal Gland
Document Summary
Amino acid derivatives-certain hormones can be built from modified amino acids-get into cells by receptor sites on cell membranes. Proteins-ex: insulin-can t get into the cells by themselves. Mechanisms of hormone actions: (review chapter 3 cell; intercellular communication) Fixed membrane receptor mechanism-in cell membrane, area for hormones and proteins to attach to allow a reaction to occur inside the cell. First messengers activate second messengers (ie camp, calcium, etc) Mobile receptor mechanism-for steroid hormones-hormone diffuses inside to cell and attaches to a receptor then it goes into the nucleus of the cell and changes the rate of protein production. Only effect cells with specific receptor for hormone-fixed or mobile receptors. Effect of hormone depends on the nature of the target cell-hormones in different places will have different effects. Hormones do not initiate reactions only control rate of reactions-speeds them up or slows them down. Overview of hormones directly responding to a parameter.
