N5315 Advanced Pathophysiology Renal and Urologic System Core Knowledge Objectives with Advanced Organizers

N5315 Advanced Pathophysiology Renal and Urologic System Core Knowledge Objectives with Advanced Organizers Anatomy and physiology of the Renal System I. Discuss the physiologic relationship between phosphorus and calcium. A. Calcium: the major cation associated with the structure of bones and teeth, serves as cofactor for blood clotting, and is required for hormone secretion and the function of cell receptors 1. Plasma membrane stability and permeability, transmission of nerve impulses, and contraction of muscles are directly related to calcium ions 2. Intracellular calcium primarily located in the mitochondria 3. Ionized calcium has the most important role in physiologic functions B. Phosphate: acts as an intracellular and extracellular anion buffer in the regulation of acid-base balance and in the form of ATP it provides energy for muscle contraction C. Calcium and phosphate has strict direct relationship (increase and decrease together) regulated by PTH, vitamin D, and calcitriol 1. Together these substances determine the amount of dietary calcium and phosphate absorbed from the intestine, the deposition and absorption of calcium and phosphate from the bone, and renal reabsorption and excretion of calcium and phosphate by the kidney 2. PTH secreted in response to low levels of calcium by the parathyroid gland a. Renal regulation requires PTH: stimulated reabsorption of calcium and inhibits reabsorption of phosphate b. Increase Ca and increased excretion of phosphate 3. Vitamin D (cholecalciferol) a. Must be activated by the liver and the kidney b. Renal acitivation begins when low levels of Ca stimulate secretion of PTH PTH acts to increase calcium reabsorption and enhance renal excretion of phosphate low calcium and increases PTH cause renal activation of Vitamin D activated Vitamin D increases absorption of calcium and phosphate in the small intestine, enhance bone calcification, and increase renal tubular reabsorption of calcium and phosphate c. In renal failure, Vitamin D is not activated and serum calcium levels decrease and phosphate levels increase 4. As calcium levels increase, opposite adapation occurs, leading to suppression of PTH, decreased Vitamin D activation, decrease intestinal absorption, and increased renal phosphate reabsorption 5. Calcitonin: thyroid gland, primarily decrease Ca levels by inhibiting osteoclast activity in bone 6. In acidosis, ionized Ca increases ; in alkalosis ionized Ca decreases (more protein available to bind with decreased H) II. Discuss how calcium and phosphorus homeostasis is altered by renal disease and the pathologic consequences. III. Examine the basic anatomy and physiology of the kidney