Renal Lecture 1 - Kidneys - Anatomical Location, Structure and Functions PDF

HPHS 232 - Renal Physiology Dr Meleshni Naicker Department of Human Physiology University of KwaZulu-Natal - Westville [email protected]  LECTURE OBJECTIVES Functional anatomy of the kidney Functions of the kidney Glomerular filtrati...

HPHS 232 - Renal Physiology Dr Meleshni Naicker Department of Human Physiology University of KwaZulu-Natal - Westville [email protected]  LECTURE OBJECTIVES Functional anatomy of the kidney Functions of the kidney Glomerular filtration Renal tubular functions Mechanisms of regulation Renal dysfunction Acid-base regulation LECTURE OUTLINE  RENAL PHYSIOLOGY LECTURE 1 Introduction Kidneys: anatomical location, structure & functions  Internal anatomy of the kidney The outer layer of the kidney is the renal cortex; it is the site of glomerular filtration as well as the convoluted tubules. The inner part of the kidney is the renal medulla; this is the location of the longer loops of Henle, and the drainage of the collecting ducts into the renal pelvis and ureter. Renal blood supply Blood supply to the kidney is organised so that each nephron is supplied by an afferent arteriole. Distribution of Blood Flow to the kidney Kidneys receive approx.1200ml blood/per minute i.e. 25% of cardiac output Cortex - 1000 ml/min (75%) Outer Medulla - 240 ml/min (20%) Inner Medulla - 60 ml/min (5%) Basic functions of the kidney 1. Glomerular filtration Basic functions of the kidney refers to the movement of fluid and solutes from the glomerular capillaries into Bowman’s space. 2. Tubular reabsorption refers to the movement of materials from the filtrate in the tubules into the peritubular capillaries. 3. Tubular secretion refers to the secretion of solutes from the peritubular capillaries into the tubules. 4. Urinary excretion = Amount filtered + Amount secreted – Amount reabsorbed of a substance