《甲状腺解剖》课件.pptVIP

Chapter 19 ENDOCRINE SYSTEM Compare the basic organization and function of the ES and the NS Describe the structural and functional organization of the hypothalamus and the pituitary and explain their relationship Discuss the locations and structures of the thyroid, parathyroid, and adrenal glands as well as the thymus and the endocrine part of the pancreas. List the hormones (and their function) produced by these glands. Briefly review the results of abnormal hormone production Endocrine System Overview Ductless glands produce hormones Gland may be entire organ or interspersed bits of tissue Chemical classification of hormones Target tissues are identified by receptors Hypothalamus Control Center for internal environment Regulates nervous and endocrine systems via 3 mechanisms: ANS centers exert nervous control on adrenal medulla ADH and Oxytocin production Regulatory hormone production (RH and IH) controls pituitary gland directly and all other endocrine glands indirectly Fig 19-3 Pituitary Gland (= Hypophysis) Structure: Infundibulum - connection to hypothalamus In the sella turcica Two parts with an embryonic double origin Posterior Pituitary = neurohypophysis Storage shed for ADH and Oxytocin (produced in ?) Anterior Pituitary = adenohypophysis production of 7 peptide hormones, see fig 19.5 Histology Fig 19-4 Hypophyseal Portal System Portal systems: two capillary networks in serial arrangement Advantage? Named after their destination: . . . Portal veins: blood vessels that link two capillary networks Fig 19-6 Thyroid Gland Anterior surface of trachea just inferior of thyroid cartilage (or Adam’s apple) Two lobes connected by isthmus Microscopic thyroid follicles produce thyroid hormone C Cells - produce calcitonin (?Ca2+) Fig 19-7 Thyroid Gland Function Thyroxin (T4) and triiodothyronine (T3) ? speed up metabolic rate Calcitonin ? lowers blood Ca2+ levels Thyroid pathologies: Hyper- and Hypothyroidism Goiter Exophthalmus H