BMS 360 Lecture Notes - Growth Factor, Lipophilicity, Homeostasis
Document Summary
Gland secretes hormone lumen throughout the body (exocrine) Gland secretes hormone interstitial fluid cells (endocrine) In cancer, cells can mutate to create growth substances that are autocrine aids cancer"s independence. Agonist ligand that binds to receptor, generates cellular response. Antagonist prevents agonist from binding, inhibits action. Downregulation too much stimulation, number of receptors for cell decreased. Passive diffusion (since it is lipophilic, can pass through cell membrane) Signal amplification necessary messengers only present in low concentrations. Substance (ion) flows down concentration gradient into cell. Ions amplify signal act as second messengers. Protein inside cell is phosphorylated upon ligand binding (activation) Kinase activated, but is not intrinsic to receptor. Trimeric ( , , ) g-protein activated by receptor binding. Subunit dissociated to act on other proteins. Binds to kinases converts them to active form. Ion channels in endoplasmic reticulum can create rapid responses. Pip2 acted on by phospholipase c dag + ip3. Ip3 acts on endoplasmic reticulum release ca2+
