Their primary function is to regulate the activity of pituitary-dependent endocrine glands. Hormones of this group are synthesized in the adenohypophysis (anterior pituitary). by physiological action hormones are classified into:Ī) effector hormones acting on target cells in tissues and organs ī) tropic or regulatory hormones. Hormones of cytosolic action realize their action via hereditary apparatus of the cell located in the nucleus.ģ. Therefore, to be able to act on a cell a hormone must first penetrate a cell and interact with the receptor. Receptors sensitive to these hormones are located inside cells. This group includes steroid hormones and reproductive hormones. phospholipase C – inositol-3-phosphate ī) hormones of intracellular (cytosolic) action. guanilate cyclase – cyclic guanosine monophosphate (cGMP) adenylate cyclase – cyclic adenosine monophosphate (cAMP) Second messengers may be the substances that participate in synaptic transmission: After that a hormone-receptor complex activates second messengers that act to couple processes occurring on the membrane and those occurring in the cytoplasm. Thus, a hormone recognizes a receptor on the membrane of a target cell and interacts with it. Receptors sensitive to these hormones, are embedded into biological membranes of target cells. By mechanism of action hormones are divided into 2 groups:Ī) hormones of membrane action (insulin, glucagon). Steroid hormones (hormones of adrenal cortex, sex hormones.Ģ. ī) proteins proper (insulin, glucagon, etc.) Ĭ) glucoproteids, e.g., follicle-stimulating hormones, leuteinizing hormones Ĭ. Here 3 subgroups can be distinguished:Ī) oligopeptides – low-molecular-weight proteins, e.g., antidiuretic hormone (vasopressin), oxytocin, gastrin, etc. Iodine-containing thyroid hormones are also derivatives of tyrosine ī. For example, adrenaline, a hormone produced by adrenal medulla, is a derivative of tyrosine. By chemical composition, hormones may be classified into 3 groups:Ī. Morphological classification of nouns.Etymological survey of the English vocabulary.Electrodes classification: definition, comparison, oxidation-reduction.Classification of Functional Styles of the English Language.Classification of English Consonants and Vowels.Articulatoty and Physiological Classification of English Sounds.The hypothalamus controls the release of hormones from the anterior pituitary by secreting a class of hypothalamic neurohormones called releasing and release-inhibiting hormones-which are released to the hypothalamo-hypophyseal portal system and act on the anterior pituitary.Главная страница | Контакты | Случайная страницаĬlassification of Hormones Читайте также: Growth hormone's major tropic effect is it releases insulin-like growth factors from the liver, which causes bone growth. ⁕Growth hormone – has both tropic and non-tropic effects. ⁕Follicle-stimulating hormone – stimulates the maturation of eggs and production of sperm. ⁕Luteinizing hormone – stimulates the release of steroid hormones in gonads-the ovary and testes. ⁕Adrenocorticotropic hormone – stimulates the adrenal cortex to release glucocorticoids. ⁕Thyroid-stimulating hormone – stimulates the thyroid gland to make and release thyroid hormone. Tropic hormones from the anterior pituitary include: The hypothalamus secretes tropic hormones that target the anterior pituitary, and the thyroid gland secretes thyroxine, which targets the hypothalamus and therefore can be considered a tropic hormone. Most tropic hormones are produced and secreted by the anterior pituitary. Tropic hormones are hormones that have other endocrine glands as their target. Freebase (5.00 / 1 vote) Rate this definition: