Transcript Document
Ieva B. Akbar Department of Physiology Faculty Of Medicine – Universitas Islam Bandung I. INTRODUCTION • Neuroendocrinology – The interaction between the central nervous system (CNS) and endocrine systems in the control of homeostasis – The control of pituitary hormone secretion by the hypothalamus – The fundamental role of the hypothalamus in controlling anterior pituitary function. The Endocrine System Pituitary Gland Anatomy Synthesis, storage and release of posterior pituitary hormone Hypothalamic and pituitary hormones Hormones of the hypothalamic anterior pituitary pathway A complex endocrine pathway II. NEURAL CONTROL OF GLANDULAR SECRETION a. Neurosecretion • The release of any neuronal secretory product from a neuron • Neurons that secrete substances directly into the blood stream to act as hormones • Neurons have basic ability to respons and integrate input from multiple neurons through specific receptors • Three types of hypothalamic neurosecretory cells b. The autonomic nervous system contribution to endocrine control The neurons system controls or modifies or both, the function of basic endocrine and exocrine glands • Anterior pituitary : releasing hormone • Pancreas, Adrenal, Pineal salivary (endocrine & exocrine) : regulated through direct innervation from autonomic neurons system Brain Postganglionic sympathetic neuron Sympathetic ganglia Preganglionic sympathetic neuron Adrenal glands Sympathetic ganglia Medulla Blood Various effector organs Epinephrine NE Heart III. HYPOTHALAMICPITUITARY UNIT a. Anatomy of the hypothalamic-pituitary unit • Adenohypophysis • Pars distalis • Pars intermedia • Pars tuberalis • Neurohypophysis b. The median eminence and hypophyseotropic neuronal system • Lies in the center of tuber cinereum A. Human hypothalamic Pituitary unit B. Midsaggital nuclear Magnetic resonance scan of the brain of a normal woman IV. CIRCUMVENTRICULAR ORGAN a. Median eminence The median eminence and neurohypophysis contain the secretory axons that control pituitary function Hypothalamic magnocellular neurons and the posterior pituitary gland b. Organum vasculosum of the lamina terminalis and the subfornical organ • Are located at the front wall of the third ventricle, the lamina terminalis • Involved in the maintenance of many processes : fluid and electrolyte balance, blood pressure, reproduction, thermaregulation c. Area postrema d. Subcommissural organ V. HYPOPHYSEOTROPIC HORMONES AND NEUROENDOCRINE AXES a. Feedback concepts in neuroendocrinology b. Endocrine rhythms c. Thyrotropin-releasing hormone - Chemistry and evolution - Clinical applications - Regulating of thyrotropin release - Feedback control : Pituitary-Thyroid Axis - Neural control : Circadian rhythm, Temperature, Starvation, Infection and inflammation d. Corticotropin-releasing hormone - Chemistry and evolution - Effect on the pituitary and mechanism of action - Clinical applications - Feedback control - Neural control - Other factors influencing secretion of corticotropin : Circadian rhythm, corticotropin release-inhibiting factor e. Growth hormone-releasing hormone Chemistry and evolution - Growth hormone-releasing hormone receptor - Effect on the pituitary and mechanism of action - Extrapituitary functions - Clinical applications Neuroendocrine regulation of growth hormone secretion - Neural control - Factors influencing secretion of growth hormone : Human growth hormone rhythms, external and metabolic signals f. Somatostatin - Chemistry and evolution - Somatostatin receptors - Effect on target tissues and mechanism of action - Clinical applications of somatostatin analogues g. Prolactin-regulating factors - Dopamine - Prolactin-releasing factors - Intrapituitary regulation of prolactin secretion - Neuroendocrine regulation of prolactin secretion - Feedback control - Neural control - Factors influencing secretion h. Gonadotropin-releasing hormone and control of the reproductive axis - Chemistry and evolution - Anatomic distribution - Embryonic development - Action at the pituitary : receptor, pulsatic gonadotropin-releasing hormone stimulation - Regulating systems - Feedback regulation - Regulation by inhibins and activins - Regulation of the ovarian cycle - Early development and puberty - Reproductive function and stress i. Leptin and the brain-gut-adipose axis - Chemistry and evolution of leptin - Effects of leptin on the hypothalamus and neuroendocrine axes - Mechanism of action - Clinical applications - Feedback control j. Neuroendocrine-immune interactions - Cytokines signal the central nervous system - Interaction of cytokines with the circumventricular organs - Interaction of cytokines at the barriers of the brain - Entry of cytokines into the brain - Interaction of cytokines with peripheral nerves - Cell groups throughout the brain responsive to cytokines A model of the central nervous system circuitry mediating the activation of the PVN or PVH and HPA axis by immune system stimulation VI. NEUROENDOCRINE DISEASE a. b. c. d. Pituitary isolation syndrome Hypophyseotropic hormone deficiency Hypophyseotropic hormone hypersecretion Neuroendicrine disorders of gonadotropin regulation - Precocious puberty - Idiopathic sexual precocity - Neurogenic precocious puberty - Hypothyroidism - Tumors of the pineal gland - Approach to the patient with precocious puberty - Management of sexual precocity - Psychogenic amenorrhea - Neurogenic hypogonadism in males e. Neurogenic disorders of prolactin regulation f. Neurogenic disorders of growth hormone decretion - Hypothalamic growth failure - Maternal deprivation syndrome and psychosocial dwarfism - Neurogenic hypersecretion of growth hormone - Diencephalic cachexia - Syndrome of inappropriate growth hormone hypersecretion g. Neurogenic disorders of cortricotropin regulation h. Genetic obesity disorders involving hypothalamic circuits i. Nonendocrine manifestations of hypothalamic disease