Chapter 8 Excretion of the Kidneys 66 A 92001 How Stuff Works
Chapter 8 Excretion of the Kidneys
Major Functions of the Kidneys Regulation of body fluid osmolarity and volume electrolyte balance acid-base balance blood pressure 2. Excretion of metabolic products foreign substances(pesticides, chemicals etc. excess substance(water, etc) 3. Secretion of erythropoitin 1, 25-dihydroxy vitamin D3(vitamin D activation) renin prostaglandin
Major Functions of the Kidneys 1. Regulation of: body fluid osmolarity and volume electrolyte balance acid-base balance blood pressure 2. Excretion of metabolic products foreign substances (pesticides, chemicals etc.) excess substance (water, etc) 3. Secretion of erythropoitin 1,25-dihydroxy vitamin D3 (vitamin D activation) renin prostaglandin
Section 1 Characteristics of renal Structure and function I. Physiological Anatomy of the Kidney
Section 1 Characteristics of Renal Structure and Function I. Physiological Anatomy of the Kidney
1. Nephron and Horrors Collecting Duct Cortex Nephron The functional Distal tubule unit of the kidney tabula Each kidney is made up of about 1 million Bowmans nephrons Descending Each nephrons has two Ascending Henle major components Collecting )Glomerulus 2)A long tube
1. Nephron and Collecting Duct Nephron: The functional unit of the kidney Each kidney is made up of about 1 million nephrons Each nephrons has two major components: 1) A glomerulus 2) A long tube
Copyright e The McGraw-Hill Companies. Inc Permission required for reproduction or display Bowman's capsule Proximal tubule Renal corpuscle(cut) Glomerulus Distal tubule Proximal tubule Cortical nephron Cortical Distal tubule nephrons have loops Juxtamedullary Juxtamedullary of Henle nephrons have that do not loops of Henle extend Cortex nephron that extend deep deep into the medulla into the Blood medulla Descending limb supply Renal corpuscle Loop of Henle(nephronic loop)- Thick ascending limb Thin ascending limb Nephron Collecting Renal pyramid of duct the medulla Cortex Renal pyramid of the medulla Papillary duct Collecting To a minor calyx duct
Cortical nephron Juxtamedullary nephron
Anatomy of Kidney Cortical nephron ■80%-90 glomeruli in outer cortex ■ short loops of henle extend only short distance into medulla blood flow through cortex is rapid cortical interstitial fluid 300 mOsmolar
Anatomy of Kidney ◼ Cortical nephron ◼ 80%-90% ◼ glomeruli in outer cortex ◼ short loops of Henle ◼ extend only short distance into medulla ◼ blood flow through cortex is rapid ◼ cortical interstitial fluid 300 mOsmolar
Anatomy of Kidney o Juxtamedullary nephron glomeruli in inner part of cortex long loops of Henle extend deeply into medulla blood flow through vasa recta in medulla is SlOW medullary interstitial fluid is hyperosmotic maintains osmolality, filtering blood and maintaining acid-base balance
Anatomy of Kidney ⚫ Juxtamedullary nephron – glomeruli in inner part of cortex – long loops of Henle ⚫ extend deeply into medulla. – blood flow through vasa recta in medulla is slow – medullary interstitial fluid is hyperosmotic – maintains osmolality, filtering blood and maintaining acid-base balance
2. The juxtaglomerular apparatus Including macula densa, extraglumerular mesangial cells, and juxtaglomerular (granular cells) cells Efferent 92001 BrooksCole.Thomson Learning Lumen of Endothelial Bowmans capsule Distal tubule Smooth Bowmans capsule Efferent arteriole capillaries Afferent arteriole acu densa Podocyte Granular cells Distal tubule Afferent arteriole
2. The juxtaglomerular apparatus Including macula densa, extraglumerular mesangial cells, and juxtaglomerular (granular cells) cells
3. Characteristics of the 18 mm Hg renal blood flow mm Hg 1. High blood flow. 1200 ml/min or 21 percent of mm Hg the cardiac output. 949 10 mm Hg 13 mm H to the cortex n Hg 2, Two capillary beds High hydrostatic pressure in glomerular capillary (about 60 mmHg) and Interstitial fluid low hydrostatic pressure pressure 6 mm Hg in peritubular capillaries Ⅴ esa recta 0 mm Hg (about 13 mmHg)
3. Characteristics of the renal blood flow: 1, High blood flow. 1200 ml/min, or 21 percent of the cardiac output. 94% to the cortex 2, Two capillary beds High hydrostatic pressure in glomerular capillary (about 60 mmHg) and low hydrostatic pressure in peritubular capillaries Vesa Recta (about 13 mmHg)
Blood flow in kidneys and other organs rgan Approx blood flow A-VO difference (mg/min/g of tissue) (mI/L) Kidney 4.00 12-15 depends on reabsorption of Heart 0.80 96 Brain 0.50 48 Skeletal muscle 0.05 (rest Skeletal muscle 1.00 (max. exercise)
Blood flow in kidneys and other organs Organ Approx. blood flow (mg/min/g of tissue) A-V O2 difference (ml/L) Kidney 4.00 12-15 (depends on reabsorption of Na+ ) Heart 0.80 96 Brain 0.50 48 Skeletal muscle (rest) 0.05 - Skeletal muscle (max. exercise) 1.00 -