Basic Endocrinology pot

[...]... 8 BASIC ENDOCRINOLOGY CHAPTER 1 Question 6: Explain the functional relation between the hypothalamus and anterior pituitary in controlling hormone release Question 7: Describe (giving examples) the various types of hormonal feedback mechanism Question 8: Draw a diagram showing the location of the principal endocrine organs in the body References • Goodman HM (1988) Introduction In Basic Medical Endocrinology, ... breast or prostate cancer is discussed in Chapter 6] 18 BASIC ENDOCRINOLOGY CHAPTER 2 Figure 2.6 Control of pituitary corticotrophin (ACTH) release by hypothalamic releasing hormone (CRH) and negative feedback loops involving the adrenal corticosteroid cortisol, acting back on the anterior pituitary and hypothalamus The secretion of CRH by the hypothalamus is primarily influenced by various stressful... prolactin (PRL), all have their major effects restricted to specific target organs 10 BASIC ENDOCRINOLOGY CHAPTER 2 Figure 2.1 Diagram showing basic anatomical features of the pituitary gland, divided into functionally-independent anterior (adenohypophysis) and posterior (neurophysis) portions and connected to the hypothalamus by the infundibular stalk The pars intermedia (intermediate lobe) is not well... cells may secrete both LH and FSH THE HYPOTHALAMUS AND PITUITARY 11 The Hypothalamic-Hypophyseal Portal System Synthesis and release of these trophic hormones is determined partly by direct feedback effects exerted by the target gland hormones (Chapter 1), and partly by specific hypothalamic releasing or inhibiting hormones These agents are secreted by specialized hypothalamic (peptidergic) neurones with... carried to target tissues via the general circulation 12 BASIC ENDOCRINOLOGY CHAPTER 2 Gonadotrophin Releasing Hormone Gonadotrophin releasing hormone (GnRH), (also known as luteinizing hormone releasing hormone (LHRH) or gonadorelin) is a linear decapeptide, that is released in a pulsatile fashion from hypothalamic GnRH neurones Although other hypothalamic and/or gonadal peptides may be involved, both... hyperthyroidism similar to Graves’ disease (see Chapter 4) 16 BASIC ENDOCRINOLOGY CHAPTER 2 Figure 2.4 Regulation of pituitary thyrotrophin (TSH) secretion via release of hypothalamic TRH and by direct negative feedback effects of the thyroid gland hormones T3 and T4 on the anterior pituitary Dopamine (DA) and somatostatin (SS) released by specific hypothalamic neurones, also exert a tonic inhibitory action... hormone release can be finely adjusted (closed-loop system) 4 BASIC ENDOCRINOLOGY CHAPTER 1 Figure 1.1 The location of principal endocrine organs in the body The secretory activity of most endocrine target organs is controlled by the anterior pituitary, which is in turn, under the influence of hypothalamic releasing hormones/factor’s released by hypothalamic nerve fibres into the pituitary blood supply Modulatory... given by intramuscular 20 BASIC ENDOCRINOLOGY CHAPTER 2 Figure 2.7 Control of prolactin secretion by hypothalamic releasing/inhibiting factors The principal prolactin-releasing hormones are TRH (thyrotrophin releasing hormone) and oxytocin (released during the infant suckling response); release is also promoted by various stress factors Secretion of dopamine (DA) by specific hypothalamic neurones, exerts... hypothalamic-hypophyseal portal system of veins, takes blood from a primary capillary bed in the median eminence, along the pituitary stalk, and enters the anterior pituitary to form a secondary bed of capillaries; the released hypothalamic hormones readily enter the portal capillaries and are then transported via the portal veins to the anterior lobe, where they exert their effects (Figure 2.2) Hypothalamic... (Figure 2.2) Hypothalamic Releasing and Inhibiting Hormones that Influence the Anterior Pituitary The actions of the principal hypothalamic hormones, and their current therapeutic uses may be summarized as follows: Figure 2.2 The hypothalamic-hypophyseal portal system Hypothalamic peptidergic neurones secrete releasing hormones that are transported by small hypophyseal portal blood vessels in the median . 8 Chapter 2: The Hypothalamus and Pituitary 9 Structure and Histology 9 Histology 10 The Hypothalamic-Hypophyseal Portal System 11 Hypothalamic Releasing. book endeavour. Basic Endocrinology for Students of Pharmacy and Allied Health Sciences is arranged into seven chapters: the first provides a basic introduction