Adrenal Hormone Mineralocorticoids Aldosterone

Transcription

1 Adrenal gland Adrenal Hormone Mineralocorticoids Aldosterone Cortex 80 % Glucocorticoids Cortisol Sex hormones Androgen Medulla 20% Catecholamines E, NE 1 2 Adrenal cortex hormones Glucocorticoid Mineralocorticoids Sex hormones Adrenal medulla Norepinephrine 20% Epinephrine 80% 3 4 Adrenal steroids biosynthesis Adrenal-pituitary feedback regulation Anxiety Stress Depression Sleep/ awake Feeding CRH Neurotransmitters ADH ACTH ACTH Cortisol ACTH Stimulate DHEA Cortisol 5 Inhibit Aldosterone 6

2 Organs Major Glucocorticoids actions Adipose tissue Lipolytic hormones FFA Liver Muscle Glycogen G-6-P Glucose precursors Glucose Glucose Amino acids Protein Actions Lipolysis Redistribution of fat Gluconeogenesis Glucose utilization sensitivity Diabetogenic effects Protein break down 7 Glucocorticoids actions CVS Vasoconstriction Maintain ECF volume & capillary intregity Free water clearance (GFR) Mineralocorticoid effects Na + retention/ K + excretion Normal muscle contraction (skeletal & cardiac M) Collagen synthesis: skin, blood vessels 8 Glucocorticoids actions Glucocorticoids actions Bone protein matrix/ Osteblast. GI Ca 2+ absorption. Renal Ca 2+ excretion Blood calcium PTH Anti-inflammation PGs, TXs, LTs Interleukin Capillary permeability Phagocytosis Anti-allergic action Immuno-suppressant Bone formation Bone resorption Osteoporosis 9 T-lymphocytes Suppress antibody 10 Abnormal glucocorticoids secretion Glucocorticoids excess Cushing s s disease Cushing s s syndrome (drug) Glucocorticoids deficit Addison s s disease (Adrenal insufficiency) 11 12

3 Cushing s s syndrome Cushing s s syndrome High risk infection Delayed wound healing Steroid diabetes Muscle wasting Osteoporosis Hypertension Appeptite Peptic ulcer ( HCl & pepsin) Gonadal disturbances Intra-ocular pressure (glaucoma) Fat deposition of central area: face & body (Truncal obesity) Inhibit skeletal growth ( GH) Steroid psychosis Cushing s s disease Addison s s disease Moon face Buffalo hump Abdominal striae Appetite Hyperpigmantation or dark tanning of skin both exposed and nonexposed parts of body Fainting / dizziness ( BP) Salt craving Hypoglycemia Addison s s disease Mineralocorticoids (aldosterone) Increase the reabsorption of Na + form the urine, sweat, saliva and the contents of gastrointestinal tract. Increase the reabsoption of water ( ECF). This is an osmotic effect directly related to increased resorption of sodium. Increase the renal excretion of K

4 Mineralocorticoids deficit Usually occur with glucocorticoid deficit Salt and water depletion Postural hypotension Dehydration Hypovolemia Hyperkalemia Hypovolemic shock Metabolic acidosis Primary case with increased ACTH Hyperpigmentation Adrenal medulla Adrenal medulla Sympathetic Adrenal gland Ach Sympathetic Ach E, NE norepinephrine Adrenal E & NE Marked deviation of homeostasis circulating hormone Adrenal cathecolamines 10%of sympathetic activity Sympathetic NE Cathecolamine actions NE and E act via α 1, α 2, β 1, β 2 Adrenergic receptors Different receptors (Cell-surface receptor) Fine regulation Intense stimulation Neurotransmitter (local hormone) circulation Different intracellular mechanisms 23 24

5 Flight or fight response Pupils dilated Salivation inhibited Increased respiration Bronchial passages dilated Increased heart rate BP Digestion inhibited Secretion of adrenal hormones Increased secretion by sweat glands Hair follicles raised Bladder sphincter relaxed Stress Reponse Heart rate, force of contraction of the heart muscle BP Constriction of blood vessels BP Dilation of bronchioles metabolic rate Lipolysis in fat cells Anatomy and histological of pancreas Islet of Langerhans Exocrine gland: enzymes Parasympathetic fibers A, α % Glucagon B, β 60-80% B cells Sympathetic fibers D, σ 8% Somatostatin D cells A cells F variable Pancreatic polypeptide Islet of langerhans:, Glucagon 29 30

6 Chain A: 21 aa Factor affecting insulin secretion Chain B: 30 aa Disulfide bridge Peptide hormone MW 6000 Amino acids GI hormones Diabetogenic H + Glucose Vagus N + B cells - a-adrenergic Somatostatin Normal blood glucose 100 mg/dl (3-5 mm) Basal plasma insulin concentration microu/ml Meals signaling a-subunit b-subunit receptor Glucose 33 Glucose Protein transport synthesis Lipid synthesis glycogen synthesis Growth and Gene expression 34 actions deficit Diabetes Millitus Protein Amino acid uptake & protein synthesis Amino acid output & amino acid oxidation CHO Glycogen synthesis Glycogenolysis Gluconeogenesis Hepatic glucose production Lipid Triglyceride synthesis Absolute: dependent diabetes mellitus (IDDM)/ Type I 5-10% Relative: Non insulin dependent diabetes mellitus (NIDDM)/ Type II 90-95% Defect in insulin secretion resistance Receptor Postreceptor Lipolysis 35 36

7 Diagnosis Diabetes Millitus A casual plasma glucose level (taken at any time of day) of 200 mg/dl or greater when the symptoms of diabetes are present. A fasting plasma glucose value of 126 mg/dl or greater. Signs and symptoms of diabetes mellitus Hyperglycemia Glucosuria (Osmotic diuresis) Hyperlipidemia Ketonemia Protein wasting Weight loss An OGTT value in the blood of 200 mg/dl or greater measured at the 2-hour interval excess Over dose insulin oma Hypoglycemia Neuroglycopenia Hunger Dizziness Coma Cathecolamine: anxiety, sweating, tachycardia Glucagon 29 amino acids identical to enteroglucagon Glucagon act by binding to its receptor and activated G protein which cause an increase in camp. Glucagon has the effect of increasing blood glucose levels (opposite effect of insulin) Factor affecting glucagon secretion Glucagon actions CHO Glycogen synthesis Glycogenolysis Lipid Lipolysis 41 Gluconeogenesis Hepatic glucose production 42

8 and glucagon cause the tight control of blood glucose concentration Catecholamines Corticosteroids 43 Growth H 44