<p> Chapter 16 Endocrine - part 2</p><p>Endocrine system</p><p>• several separate organs • release hormone into capillaries • hormone transported in blood</p><p>• endocrine vs exocrine Endocrine Glands</p><p>• Hypothalamus • Pituitary • Pineal gland • Thyroid • Parathyroid • Thymus • Adrenal Cortex • Adrenal Medulla • Pancreas • Ovary • Testes • several others things to know</p><p>• endocrine gland • gland + hormone(s) produced • hormone + its action • diseases</p><p> types of hormones</p><p>• direct hormones target = non-endocrine tissue • tropic hormones target = endocrine glands – releasing hormones from hypothalamus – stimulating hormones from ant. pituitary • prohormone inactive forms</p><p>Thyroid gland</p><p>• follicular cells • produce thyroid hormone • lumen • stores colloid • parafollicular (C) cells – produce calcitonin</p><p>Thyroid hormone</p><p>• thyroid hormone thyroxine T4 tri-iodothyronine T3 • effects: – calorigenic stim gene/enzymes of cell respiration uncoupling enzymes increase basal metabolic rate = heat </p><p>– metabolic protein synthesis increase heart rate and BP</p><p>– growth nervous system development muscle, skeletal development</p><p>– see table 16.2 Thyroid hormone synthesis</p><p>• thyroglobulin synthesis</p><p>• iodination I2 added to tyrosine</p><p>• storage colloid = thyroglobin + I2</p><p>• cleavage T4 and T3 break from colloid stim by TSH</p><p>• secretion exocytosis</p><p>• transport TBG thyroxine-binding globulin</p><p> control of T4 • stimulus: TSH (thyroid stimulating hormone)</p><p>– low blood T4 – low body temp – pregnancy</p><p>• inhibited by any inhibition of TSH</p><p>– high blood T4 – somatostatin</p><p>Diseases of Thyroid hormone</p><p>• Grave’s Disease hyperthyroidism –  BMR ;  HR – weight loss ; sweating – exopthalmos • Myxedema hypothyroidism (adult) – fluid accumulation – weakness; lethargy ; mental “sluggishness” –  BMR ; weight gain ; chilled • Cretinism hypothyroidism (congenital) – decreased growth; and mental development • Goiter – thyroid tumor</p><p>– decreased I2 increased TSH  increase colloid</p><p>Calcitonin</p><p>• = thyrocalcitonin • parafollicular (C) cells • effects: decrease blood calcium deposit calcium into bone</p><p>• stimulus: high blood Calcium</p><p>Parathryroid gland</p><p>• Parathyroid hormone – PTH = parathormone</p><p>• effects : increase blood calcium increase Ca++ absorption increase Ca++ reabsorption remove Ca++ from bone</p><p>• stimulus: low blood calcium</p><p>Adrenal gland</p><p>• 2 separate glands adrenal cortex outer adrenal medulla inner</p><p>Adrenal medulla</p><p>• 2 catecholamines epinephrine norepinephrine</p><p>• effects: – “adrenaline rush” “fight or flight” increase heart rate , BP bronchodilation increase BMR increase alertness</p><p>– increase blood glucose</p><p>• stimulus: Sympathetic nervous system</p><p>Adrenal cortex hormones</p><p>• hormones: corticosteroids – mineralcorticoids aldosterone</p><p>– glucocorticoids cortisol</p><p>– gonadocorticoids androgens</p><p> mineralcorticoids</p><p>• aldosterone • effects: • increases Na levels in blood and tissue fluid – stim transcription of Na-K ATPase in kidney + – increases reabsorption Na into blood • increase blood volume • increase BP • stimulus: renin-angiotensin low blood Na ACTH</p><p> glucocorticoids</p><p>• cortisol “stress hormone” • “ glucose sparing” • increase blood glucose glycogenolysis • fat catabolism gluconeogenesis • protein catabolism more AA for repair • anti-inflammatory limit immune system • affects memory • stimulus: ACTH stress inflammation Gonadocorticoids</p><p>• androgens : – males convert to testosterone – female convert to estradiol • effects: puberty sex drive minimal compared to gonad production</p><p>Diseases of Adrenal Cortex</p><p>• Cushing’s increased Cortisol – ACTH producing tumor ant pituitary , lung – pharmaceutical doses – cushingoid features: moon face : buffalo hump steroid diabetes osteoporosis - fractures low inflammatory response</p><p>• Addison’s Disease decreased Aldosterone , Cortisol • low Na ; increase K levels • low BP • hypoglycemia Diseases of Adrenal Medulla</p><p>• pheochromocytoma chromaffin cell tumor – increased epinephrine effects</p><p>Pancreas</p><p>• pancreatic islets = islets of Langerhans – alpha (α) cells glucagon – beta (β) cells insulin • somatostatin Glucagon</p><p>• effects: increase blood glucose – liver - glycogenolysis gluconeogenesis lipolysis</p><p>• stimulus: low blood glucose sympathetic n.s.</p><p>Insulin</p><p>• effects: decrease blood glucose – the most anabolic hormone • increase glycogenesis (storage) • increase protein synthesis and lipogenesis – increase membrane transport of glucose • increase carrier proteins GLUT4 – increase cell respiration – decrease gluconeogenesis , lipolysis</p><p>• stimulus: high blood glucose parasympathetic n.s. glucagon Insulin production</p><p>• glucose enters beta cells GLUT2 channel • increases cell respiration - ATP + • ATP closes K channels - depolarization ++ • depolar opens voltage gated Ca channels ++ • Ca enters beta cell ++ • Ca stim exocytosis of insulin</p><p> somatostatin</p><p>• same as hypothalamic hormone (GHIH) – inhibits GH (growth hormone) • inhibit TSH (thyroxine) • inhibit gastric activity</p><p> glucose related hormones</p><p>• decrease blood glucose : – insulin • increase blood glucose : – glucagon for body if low glucose – epinephrine for N.S. if immediate stress – cortisol for N.S. if long term stress – growth hormone for growth – thyroxine for cell respiration, heat Diseases of Pancreas</p><p>• hypoglycemia = low blood glucose • hyperglycemia = high blood glucose • glucosuria • Polyuria • Polydipsia • Polyphagia • Diabetes Mellitus hyperglycemia – type 1 Insulin dependent IDDM – congenital (autoimmune) decrease Beta cells – type 2 non Insulin dependent NIDDM – developed – decrease Insulin receptors on target cells Thymus</p><p>• thymic hormones • maturation of T lymphocytes</p><p>Pineal gland</p><p>• = epithalamus • melatonin – circadian rhythms – inhibit RAS • stim by hypothalamus</p><p>Ovary</p><p>• estradiol follicle • progesterone corpus luteum </p><p>Ovary</p><p>• estradiol follicle – effects: ovum development uterus development mammary duct development</p><p>– stimulus: FSH</p><p>• progesterone corpus luteum , placenta – effects: uterus development mammary gland development</p><p>– stimulus: LH , hCG</p><p>• inhibin inhibits FSH, LH Testes</p><p>• testosterone interstitial cells – effects: sperm maturation accessory sex glands</p><p>– stimulus: ICSH</p><p>• inhibin sustentacular cells – effects: inhibits FSH</p><p>Hypothalamus</p><p>• “master gland” of the endocrine system • direct hormones – ADH = antidiuretic hormone urine concentration decrease blood Osm</p><p>– oxytocin uterine contractions milk secretion</p><p>• regulatory hormones controls Pituitary gland – RH = releasing hormones (factors) – IH = inhibitory hormones</p><p>Pituitary</p><p>• = Hypophysis • Posterior Pituitary neurohypophysis • neural connection to hypothalamus • Anterior Pituitary adenohypophysis • blood connection to hypothalamus • Posterior Pituitary</p><p>• extension of the Hypothalamus • hypothalamic-hypophyseal tract – axons from Hypothalamus</p><p>• hormones made in hypothalamus released from posterior pituitary</p><p>Posterior Pituitary</p><p>• ADH Antidiuretic hormone (vasopressin) – effects: increase water reabsorption – kidney decrease blood Osm increase blood volume, BP</p><p>– stimulus: increase osmolarity</p><p>• oxytocin – effects: uterine contractions milk release</p><p>– stimulus: stretch of uterus nursing Anterior Pituitary</p><p>• = adenohypophysis</p><p>• hypophyseal portal system • vascular system betw hypothalamus and ant. pituitary</p><p>• direct hormones specific body responses</p><p>• stimulating hormones control other endocrine glands Anterior Pituitary – direct hormones</p><p>• GH growth hormone = somatotropic hormone – effects: mitosis protein synthesis Insulin-like growth factors increase blood glucose</p><p>– stim: GHRH ; low GH ; exercise • PRL prolactin – effect: milk production – stim nursing PRH</p><p>• LH luteinizing hormone ovulation Anterior Pituitary – stimulating hormones</p><p>• TSH thyroid stimulating hormone thyrotropin • ACTH adrenocorticotropic hormone corticotropin • FSH follicle stimulating hormone folliculotropin • LH luteinizing hormone luteotropin • ICSH interstitial cell stimulating hormone • GH somatotropin</p><p>• these stimulate target tissue to release hormone ; grow • controlled by Releasing hormones from hypothalamus</p><p> stimulating hormone effect</p><p>• ant pituitary other endocrine glands TSH thyroid thyroxine ACTH adrenal cortex cortisol FSH follicle estrogen LH corpus luteum progesterone ICSH interstitial cells testosterone GH liver insulin-like growth factors</p><p> hypothalamus – releasing factors</p><p>• hypothalamus ant. pituitary growth hormoneRH GHRH GH prolactin RH PRH PRL corticotropicRH CRH ACTH thyrotropicRH TRH TSH gonadotropicRH GnRH (FHRH) FSH “ GnRH (LHRH) LH growth hormoneIH GHIH inhibit GH gonadotropicIH GnIH inhibit FSH, LH</p><p>• ** hypothalamus controls all pituitary production - there is a regulating hormone from hypothalamus for every pituitary hormone</p><p>Who’s the Boss ?</p><p>• master gland? • “private controls the general” • target gland hormones control the hypothalamus and anterior pituitary • negative feedback • positive feedback: estradiol stim LH for ovulation not so during pregnancy</p><p> diseases of Growth Hormone</p><p>• increased GH: • Gigantism • increased length of long bones • congenital • Acromegaly • increased size of facial bones, hands • pituitary tumor ; adult • decreased GH: • Pituitary Dwarfism • decreased height ; normal proportions • congenital other endocrine structures</p><p>• heart atrial natriuretic peptide ANP • kidney renin erythropoietin calcitriol</p><p>• brain brain natriuretic peptide BNP • skin cholecalciferol (Vitamin D) • liver angiotensin • digestive tract gastrin secretin cholecystokinin</p><p>• adipose estrogens BP hormones</p><p>• antidiuretic hormone raise BP • epinephrine raise BP • cortisol raise BP • renin-angiotensin raise BP • thyroxine raise BP • atrial natriuretic peptide lower BP</p><p> endocrine reflex path</p><p>• control reflex path from stimulus to response • stimulus = change in condition</p><p>• afferent signal stimulus - change in condition • receptor endocrine gland • integration endocrine gland • efferent signal hormone • effector organ , tissue response</p>