Objectives Water Balance To present the homeostasis mechanism of Intake must equal loss water balance and water replacement. Intake To explore the regulatory mechanisms that > Mouth (food and water) govern water balance. govern water balance. > Cellular metabolism 2500 ml/day Loss 2500 ml/day (majority lost via urine) Thirst Mechanism Regulation of Water Intake Registered in the hypothalamus Importance of regulation: A region called the thirst center responds - to maintain Blood Pressure when plasma osmolality increases only 2 - - to maintain intracellular solute conc. 3%. Main stimulus for thirst. - to maintain intracellular solute conc. When Blood Volume decreases (10 -15% Endocrine regulation: required change) this stimulates the same ADH – Retaining water for ^ BP response perception i.e. the need to ingest Aldosterone - ^ BV water. Factors triggering ADH release Reduced blood volume Prolonged fever Excessive sweating Vomiting Diarrhea Severe blood loss Traumatic burns Edema Disorders of Water Balance Revisited I. Dehydration Pg 8 Atypical accumulation of fluid in the (IF) Water output exceeds intake. Factors: Negative fluid balance. Increased BP II. Hypotonic Hydration/ Over -hydration Inflammatory response Hypoproteinemia Excessive electrolyte dilution Increased capillary permeability Leads to severe metabolic disturbances Increased hydrostatic pressure in the capillaries: Incompetent venous valves III. Edema Localized blood vessel blockage Congestive heart failure High blood volume Electrolytes Assignment Electrolyte balance specifically refers to the Matrix table for balance of salts in the body. Electrolyte importance Characteristics > Intake – food and drink Name of Disorders > Outflow – Perspiration, feces and urine Symptoms of Disorders Kidneys play a key role in controlling excretion of electrolytes Find on Instructor Website – fill out as per i.e Reabsorption & Secretion assigned topic for Wed..