URINARY SYSTEM

2. URINARY SYSTEM ORGANS KIDNEYS (2) URETERS (2) URINARY BLADDER URETHRA

4. KIDNEY FUNCTIONS CONTROL BLOOD VOLUME AND COMPOSITION

5. KIDNEY FUNCTIONS FILTER BLOOD PLASMA, ELIMINATE WASTES REGULATE BLOOD VOLUME, PRESSURE REGULATE FLUID OSMOLARITY SECRETE RENIN SECRETE ERYTHROPOIETIN (EPO) REGULATE PCO2, ACID-BASE BALANCE SYNTHESIZE CALCITROL (VITAMIN D) DETOXIFY FREE RADICALS, DRUGS GLUCONEOGENESIS

6. METABOLIC WASTES METABOLISM PRODUCES WASTES ESP. CO2, NITROGENOUS WASTES RESPIRATORY SYSTEM REMOVES CO2 URINARY SYSTEM REMOVES BOTH CO2 AND NITROGENOUS WASTES

7. NITROGENOUS WASTES PRODUCTS OF PROTEIN METABOLISM PROTEIN ? AMINO ACIDS REASSEMBLED INTO PROTEINS EXCESS METABOLIZED FIRST STEP IS REMOVAL OF AMINO GROUP AMMONIA (NH3) IS EXCEEDINGLY TOXIC 2NH3 + CO2 ?H2NC0NH2 (UREA) UREA IS LESS TOXIC THAN AMMONIA UREA COMPRISES ~50% OF NITROGENOUS WASTES

8. NITROGENOUS WASTES PRODUCTS OF NUCLEIC ACID METABOLISM NUCLEIC ACIDS ? NUCLEOTIDES NITROGENOUS BASES REMOVED CONVERTED TO URIC ACID LESS TOXIC THAN AMMONIA LESS ABUNDANT THAN UREA

9. NITROGENOUS WASTES PRODUCTS OF METABOLISM OF CREATINE PHOSPHATE ? CREATININE LESS TOXIC THAN AMMONIA LESS ABUNDANT THAN UREA

11. NITROGENOUS WASTES RENAL FAILURE ? AZOTEMIA ACCUMULATION OF NITROGENOUS WASTES IN BLOOD AZOTEMIA ? UREMIA MANY NEGATIVE EFFECTS E.G., DIARRHEA, VOMITING, ETC. ULTIMATELY LETHAL

12. EXCRETION REMOVAL OF WASTES RESPIRATORY SYSTEM CO2, WATER INTEGUMENTARY SYSTEM WATER, SALTS, LACTIC ACID, UREA DIGESTIVE SYSTEM WATER, SALTS, CO2, LIPIDS, BILE PIGMENTS, CHOLESTEROL, ETC. URINARY SYSTEM METABOLIC WASTES, TOXINS, DRUGS, HORMONES, SALTS, H+, WATER

13. KIDNEY ANATOMY PROTECTED BY THREE CONNECTIVE TISSUE LAYERS RENAL FASCIA ATTACHES TO ABDOMINAL WALL ADIPOSE CAPSULE FAT CUSHIONING KIDNEY RENAL CAPSULE FIBROUS SAC PROTECTS FROM TRAUMA AND INFECTION

14. KIDNEY ANATOMY GROSS ANATOMY RENAL SINUS RENAL PARENCHYMA

15. KIDNEY ANATOMY RENAL SINUS SURROUNDED BY RENAL PARENCHYMA CONTAINS BLOOD & LYMPH VESSELS, NERVES, URINE-COLLECTING STRUCTURES

16. KIDNEY ANATOMY RENAL PARENCHYMA GLANDULAR TISSUE FORMS URINE TWO ZONES OUTER CORTEX INNER MEDULLA

17. KIDNEY ANATOMY RENAL PARENCHYMA RENAL PYRAMIDS EXTENSIONS OF CORTEX (RENAL COLUMNS) DIVIDE MEDULLA INTO 6 � 10 RENAL PYRAMIDS PYRAMID + OVERLYING CORTEX = LOBE POINT OF PYRAMID = PAPILLA PAPILLA NESTED IN CUP (MINOR CALYX) 2 � 3 MINOR CALICES ? MAJOR CALYX 2 � 3 MAJOR CALICES ? RENAL PELVIS RENAL PELVIS ? URETER

19. KIDNEY ANATOMY: NEPHRONS NEPHRONS FUNCTIONAL UNITS OF KIDNEY ~1.2 MILLION PER KIDNEY THREE MAIN PARTS BLOOD VESSELS RENAL CORPUSCLE RENAL TUBULE

20. NEPHRONS BLOOD VESSELS SERVICING KIDNEY SUPPLIED BY RENAL ARTERY ~21% OR CARDIAC OUTPUT (MASS IN ONLY ~ 0.4%) ? ? ?AFFERENT ARTERIOLES ? CAPILLARY CLUSTER (GLOMERULUS)

21. NEPHRONS BLOOD VESSELS SERVICING KIDNEY GLOMERULUS FENESTRATED CAPILLARIES CAPILLARY FILTRATION IN GLOMERULUS INITIATES URINE PRODUCTION FILTRATE LACKS CELLS & PROTEINS DRAINED BY EFFERENT ARTERIOLE ?PERITUBULAR CAPILLARIES ? ? ? ? RENAL VEIN

24. NEPHRONS RENAL CORPUSCLE GLOMERULUS PLUS CAPSULE GLOMERULUS ENCLOSED IN TWO-LAYERED GLOMERULAR CAPSULE �BOWMAN�S CAPSULE� FLUID FILTERS FROM GLOMERULAR CAPILLARIES �GLOMERULAR FILTRATE� FLUID COLLECTS IN CAPSULAR SPACE FLUID FLOWS INTO RENAL TUBULE

26. NEPHRONS RENAL TUBULE LEADS FROM GLOMERULAR CAPSULE ENDS AT TIP OF MEDULLARY PYRAMID ~3 CM LONG FOUR MAJOR REGIONS PROXIMAL CONVOLUTED TUBULE NEPHRON LOOP DISTAL CONVOLUTED TUBULE COLLECTING DUCT

28. NEPHRONS RENAL TUBULE PROXIMAL CONVOLUTED TUBULE (PCT) ARISES FROM GLOMERULAR CAPSULE LONGEST, MOST COILED REGION PROMINENT MICROVILLI FUNCTION IN ABSORPTION MUCH CONTACT WITH PERITUBULAR CAPILLARIES

31. NEPHRONS RENAL TUBULE NEPHRON LOOP (�LOOP OF HENLE�) �U� � SHAPED, DISTAL TO PCT DESCENDING AND ASCENDING LIMBS THICK SEGMENTS ACTIVE TRANSPORT OF SALTS HIGH METABOLISM, MANY MITOCHONDRIA THIN SEGMENTS PERMEABLE TO WATER LOW METABOLISM

32. NEPHRONS RENAL TUBULE DISTAL CONVOLUTED TUBULE (DCT) COILED, DISTAL TO NEPHRON LOOP SHORTER THAN PCT LESS COILED THAN PCT VERY FEW MICROVILLI CONTACTS AFFERENT AND EFFERENT ARTERIOLES (REGULATION IMPARTED) CONTACT WITH PERITUBULAR CAPILLARIES

34. NEPHRONS RENAL TUBULE COLLECTING DUCT DCTs OF SEVERAL NEPHRONS EMPTY INTO A COLLECTING DUCT PASSES INTO MEDULLA SEVERAL MERGE INTO PAPILLARY DUCT (~30 PER PAPILLA) DRAIN INTO MINOR CALYX

36. URINE FORMATION OVERVIEW BLOOD PLASMA ???? URINE FOUR STEPS GLOMERULAR FILTRATION TUBULAR REABSORPTION TUBULAR SECRETION WATER CONSERVATION

38. URINE FORMATION GLOMERULAR FILTRATION: MEMBRANE CAPILLARY FLUID EXCHANGE WATER AND SOME SOLUTES PASS FROM BLOOD INTO CAPSULAR SPACE OF NEPHRON BARRIERS FENESTRATED CAPILLARY ENDOTHELIUM PORES EXCLUDE CELLS, ETC. BASEMENT MEMBRANE OBSTACLE TO ANIONS FILTRATION SLITS OBSTACLE TO ANIONS

39. URINE FORMATION GLOMERULAR FILTRATION: MEMBRANE SMALL MOLECULES PASS THROUGH WATER ELECTROLYTES GLUCOSE AMINO ACIDS NITROGENOUS WASTES VITAMINS ETC. NORMALLY NOT RBCs, PLASMA PROTEINS

40. URINE FORMATION GLOMERULAR FILTRATION: PRESSURE SIMILAR TO CAPILLARY FILTRATION ELSEWHERE DIFFERENCES: BLOOD HYDROSTATIC PRESSURE (BHP) MUCH HIGHER (~60 mmHg) AFFERENT ARTERIOLE LARGER THAN EFFERENT BHP DROPS VERY LITTLE NO REABSORPTION AT VENOUS END

41. URINE FORMATION GLOMERULAR FILTRATION: RATE ~20% OF FLUID REMOVED FROM BLOOD VIA FILTRATION 180 LITERS OF FILTRATE PER DAY 60 X PLASMA IN BODY ~99% REABSORBED

42. URINE FORMATION TUBULAR REABSORPTION GLOMERULAR CAPILLARIES INVOLVED IN FILTRATION FILTRATION INTO GLOMERULAR CAPSULE PERITUBULAR CAPILLARIES INVOLVED IN REABSORPTION REABSORPTION FROM PROXIMAL CONVOLUTED TUBULE, ETC.

43. URINE FORMATION TUBULAR REABSORPTION PERITUBULAR CAPILLARIES HIGH OSMOTIC PRESSURE RESULT OF WATER LOSS LOW HYDROSTATIC PRESSURE RESULT OF EFFERENT ARTERIOLE DIAMETER CONTACT WITH PROXIMAL CONVOLUTED TUBULE, ETC. THESE FACTORS FAVOR REABSORPTION

44. URINE FORMATION TUBULAR REABSORPTION PROXIMAL CONVOLUTED TUBULE BLOOD REABSORBS ~65% OF FILTRATE LONG NUMEROUS MICROVILLI RETURNS FLUID TO PERITUBULAR CAPILLARIES ENERGY-REQUIRING NUMEROUS MITOCHONDRIA ~6% OF RESTING ATP REQUIREMENT

45. URINE FORMATION TUBULAR REABSORPTION IN PCT PCT ? EXTRACELLULAR FLUID ? PERITUBULAR CAPILLARIES ROUTES OF REABSORPTION TRANSCELLULAR THROUGH EPITHELIAL CELLS OF PCT PARACELLULAR BETWEEN EPITHELIAL CELLS OF PCT LEAKY TIGHT JUNCTIONS

46. URINE FORMATION TUBULAR REABSORPTION IN PCT WHAT GETS REABSORBED? SODIUM, CHLORIDE, & OTHER ELECTROLYTES GLUCOSE AMINO ACIDS WATER PROTEIN NITROGENOUS WASTES ETC.

47. URINE FORMATION TUBULAR REABSORPTION IN PCT SODIUM (Na+) MOST ABUNDANT CATION IN FILTRATE TRANSCELLULAR REABSORPTION SIMPLE & FACILITATED DIFFUSION INTO EPITHELIAL CELL (PASSIVE TRANSPORT) FROM EPITHELIAL CELL ? ECF (ACTIVE TRANSPORT) PERICELLULAR REABSORPTION ECF ? PERITUBULAR CAPILLARIES (PASSIVE) SODIUM CONCENTRATION GRADIENT DRIVES REABSORPTION OF OTHER SUBSTANCES

48. URINE FORMATION TUBULAR REABSORPTION IN PCT GLUCOSE & AMINO ACIDS TRANSCELLULAR REABSORPTION SODIUM-GLUCOSE COTRANSPORT (ACTIVE TRANSPORT) SODIUM-AMINO ACID COTRANSPORT (ACTIVE TRANSPORT) PASSIVE TRANSPORT FROM EPITHELIAL CELL TO EXTRACELLULAR FLUID PASSIVE UPTAKE BY PERITUBULAR CAPILLARIES

49. URINE FORMATION TUBULAR REABSORPTION IN PCT WATER TUBULAR FLUID HYPOTONIC TO INTRACELLULAR AND EXTRACELLULAR FLUIDS TRANSCELLULAR REABSORPTION PASSIVE TRANSPORT PERICELLULAR REABSORPTION PASSIVE TRANSPORT PASSIVE UPTAKE BY PERITUBULAR CAPILLARIES CONSTANT RATE OF WATER REABSORPTION MODULATED RATES ELSEWHERE IN NEPHRON

50. URINE FORMATION TUBULAR REABSORPTION IN PCT CHLORIDE (Cl-) TRANSCELLULAR AND PARACELLULAR REABSORPTION TYPICALLY FOLLOWS SODIUM ION (Na+)

51. URINE FORMATION TUBULAR REABSORPTION IN PCT OTHER ELECTROLYTES K+, Mg+, Ca++ PARACELLULAR & TRANSCELLULAR REABSORPTION SO42-, PO42-, NO3- NOT REABSORBED

52. URINE FORMATION TUBULAR REABSORPTION IN PCT PROTEIN SMALL AMOUNT IN FILTRATE TRANSCELLULAR REABSORPTION ENTERS EPITHELIAL CELLS VIA PINOCYTOSIS (ENDOCYTOSIS) HYDROLYSIS INTO AMINO ACIDS PASSIVE TRANSPORT OF AMINO ACIDS INTO EXTRACELLULAR FLUID PASSIVE UPTAKE BY PERITUBULAR CAPILLARIES

53. URINE FORMATION TUBULAR REABSORPTION IN PCT NITROGENOUS WASTES UREA PASSIVELY REABSORBED WITH WATER ~50% OF UREA REABSORBED (INADVERTENTLY) URIC ACID MOST REABSORBED (SECRETED LATER) CREATININE NOT REABSORBED PASSIVE UPTAKE BY PERITUBULAR CAPILLARIES

54. URINE FORMATION TUBULAR REABSORPTION IN NEPHRON LOOP CONCENTRATE URINE, CONSERVE WATER REABSORB ~20% OF WATER IN FILTRATE THIN SEGMENTS PASSIVE TRANSPORT THICK SEGMENT IMPERMEABLE TO WATER REABSORB ~25% OF Na+, K+, Cl- COTRANSPORT PROTEINS IN THICK SEGMENTS ACTIVE TRANSPORT

55. URINE FORMATION TUBULAR REABSORPTION IN DCT CONCENTRATE URINE, CONSERVE WATER 36 LITERS/DAY ENTERS DCT REABSORB WATER FROM FILTRATE REABSORB SALTS SUBJECT TO HORMONAL CONTROL ESP. ALDOSTERONE, ANTIDIURETIC HORMONE (ADH), ATRIAL NATRIURETIC FACTOR (ANF) PCT AND NEPHRON LOOP ARE NOT SUBJECT TO HORMONAL CONTROL

57. URINE FORMATION TUBULAR SECRETION CHEMICALS EXTRACTED FROM PERTUBULAR CAPILLARIES CAPILLARIES ? RENAL TUBULE FUNCTIONS WASTE REMOVAL ESP. NITROGENOUS WASTES, DRUGS ACID-BASE BALANCE SECRETION OF H+, HCO3- REGULATION OF pH OF BODY FLUIDS

58. URINE FORMATION WATER CONSERVATION COLLECTING DUCT RECEIVES FROM SEVERAL NEPHRONS REABSORBS H20, CONCENTRATES URINE BEGINS ISOTONIC TO BLOOD PLASMA BECOMES UP TO 4 TIMES MORE CONCENTRATED CONCENTRATION OF URINE DEPENDENT UPON BODY�S STATE OF HYDRATION

61. RENAL FUNCTION URINALYSIS EXAMINATION OF PHYSICAL AND CHEMICAL PROPERTIES OF URINE CAN DETERMINE PHYSIOLOGICAL STATE OF TISUES DIAGNOSTICALLY VALUABLE VARIOUS CHARACTERISTICS EVALUATED

62. RENAL FUNCTION URINALYSIS PROPERTIES EVALUATED APPEARANCE ODOR SPECIFIC GRAVITY OSMOLARITY pH CHEMICAL COMPOSITION

63. RENAL FUNCTION URINE VOLUME NORMALLY 1 � 2 LITERS PER DAY > 2 LITERS / DAY = POLYURIA CAUSES: FLUID INTAKE, DIABETES, DRUGS < 500 ML / DAY = OLIGURIA CAUSES: KIDNEY DISEASE, DEHYDRATION, CIRCULATORY SHOCK, PROSTATE ENLARGEMENT, ETC. < 100 ML / DAY = ANURIA ? AZOTEMIA

64. RENAL FUNCTION URINE VOLUME DIABETES 7+ TYPES CHRONIC POLYURIA GENERALLY FROM HIGH GLUCOSE CONCENTRATION IN RENAL TUBULE GENERALLY RESULTS FROM HIGH GLUCOSE IN BLOOD OSMOTIC REABSORPTION OF WATER INHIBITED RESULTS IN DEHYDRATION

65. RENAL FUNCTION URINE VOLUME DIURETICS CHEMICALS THAT INCREASE URINE VOLUME MODE OF ACTION INCREASE GLOMERULAR FILTRATION E.G., CAFFEINE DILATES AFFERENT ARTERIOLES REDUCE TUBULAR REABSORPTION E.G., ETHANOL INHIBITS ADH SECRETION FUROSEMIDE (LASIX) INHIBITS SODIUM REABSORPTION

66. URINE PRODUCTION URINE IS PRODUCED CONTINUALLY URINE IS ELIMINATED PERIODICALLY URINE MUST BE TEMPORARILY STORED

67. URINE STORAGE URETERS CARRY URINE FROM KIDNEYS TO URINARY BLADDER VIA PERISTALSIS RHYTHMIC CONTRACTION OF SMOOTH MUSCLE ENTER BLADDER FROM BELOW PRESSURE FROM FULL BLADDER COMPRESSES URETERS AND PREVENTS BACKFLOW

68. URINE STORAGE URETERS SMALL DIAMETER EASILY OBSTRUCTED OR INJURED BY KIDNEY STONES (RENAL CALCULI)

69. URINE STORAGE URETERS KIDNEY STONES HARD GRANULE, OFTEN JAGGED Ca2+, PO42-, URIC ACID, AND PROTEIN FORM IN RENAL PELVIS USUALLY SMALL, PASS UNDETECTED LARGE AND JAGGED CALCULI PAINFUL CAUSED BY HYPERCALCEMIA, DEHYDRATION, pH IMBALANCES, ETC. TREATMENT: PASS, SURGERY, ULTRASONICS

70. URINE STORAGE URINARY BLADDER MUSCULAR SAC WRINKLES TERMED RUGAE OPENINGS OF URETERS COMMON SITE FOR BLADDER INFECTION

71. URINE ELIMINATION URETHRA CONVEYS URINE FROM BODY INTERNAL URETHRAL SPHINCTER RETAINS URINE IN BLADDER SMOOTH MUSCLE, INVOLUNTARY EXTERNAL URETHRAL SPHINCTER PROVIDES VOLUNTARY CONTROL OVER VOIDING OF URINE

72. URINE ELIMINATION URETHRA 3 � 4 CM LONG IN FEMALES BOUND BY CONNECTIVE TISSUE TO ANTERIOR WALL OF VAGINA URETHRAL ORIFICE EXITS BODY BETWEEN VAGINAL ORIFICE AND CLITORIS

74. URINE ELIMINATION URETHRA ~18 CM LONG IN MALES PROSTATIC URETHRA ~2.5 CM LONG, URINARY BLADDER ? PROSTATE MEMBRANOUS URETHRA ~0.5 CM, PASSES THROUGH FLOOR OF PELVIC CAVITY PENILE URETHRA ~15 CM LONG, PASSES THROUGH PENIS

76. URINE ELIMINATION URINATION (MICTURITION) ~200 ML OF URINE HELD DISTENSION INITIATES DESIRE TO VOID INTERNAL SPHINCTER RELAXES INVOLUNTARILY SMOOTH MUSCLE EXTERNAL SPHINCTER VOLUNTARILY RELAXES SKELETAL MUSCLE POOR CONTROL IN INFANTS BLADDER MUSCLE CONTRACTS URINE FORCED THROUGH URETHRA

77. URINARY DISORDERS RENAL INSUFFICIENCY EXTENSIVE NEPHRON DESTRUCTION KIDNEYS UNABLE TO SUSTAIN HOMEOSTASIS ? AZOTEMIA, ACIDOSIS ? UREMIA CAUSES CHRONIC KIDNEY INFECTIONS TRAUMA HEAVY METAL OR SOLVENT POISONING Hg, Pb, CCl4, ETC. RENAL TUBULE BLOCKAGE ATHEROSCLEROSIS, REDUCED BLOOD FLOW TO KIDNEY GLOMERULONEPHRITIS (AUTOIMMUNE DISEASE)

78. URINARY DISORDERS RENAL INSUFFICIENCY TREATMENT BY HEMODIALYSIS WASTES ARTIFICIALLY CLEARED FROM BLOOD BLOOD PUMPED FROM RADIAL ARTERY TO A DIALYSIS MACHINE HEPARIN PREVENTS CLOTTING DURING PROCESS WASTES REMOVED BY SIMPLE DIFFUSION BLOOD RETURNED THROUGH A VEIN TYPICALLY 4 � 8 HOURS, 3X / WEEK