RENAL URINARY SYSTEM
SESSION TITLE: Renal Physiology – all sessions
SESSION: 4, 12 - 18
INSTRUCTOR: Dennis Wolff, Ph.D.
REQUIRED READING: on the kidney
OBJECTIVES: After reading the text, attending the lecture, labs, and tutorials, the student should be able to:
Lecture #4: Body Fluids & Compartments
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Understand how body fluid compartments differ with respect to volumes and ionic composition
Understand the driving forces responsible for fluid shifts across cell membranes and the capillary wall
Understand the following terms: molarity, equivalence, osmotic pressure, osmolarity, osmolality, oncotic pressure and tonicity
Understand the causes and consequences of pathophysiological expansion and contraction of the extracellular and intracellular volumes
Understand the ICF and ECF volume changes associated with the infusion of isotonic, hypotonic or hypertonic saline, 5% albumin and 5% dextrose
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I obviously cannot tell you my exam questions, but I believe I can help you study by explaining how I write them.
- The first thing I do is pick a word/short phrase that I plan to use to represent a “big picture” concept.
- Next, I try to write a stem in such a manner that if you understand the concept, that word/phrase will immediately be among those that pop into your mind
- Last, is the hardest part: coming up with wrong answers that are clearly wrong but could seem plausible to someone who has not studied the material. With rare exception, the wrong answers are chosen from among the other concepts in the same lecture
Therefore, my advice for studying is to:
- pick short words/phrases
- practice coming up with stems
- always establish foils for them, making sure to understand why the foils are wrong.
Question your friends and have them question you using this approach: For example, in this lecture, my choice for a correct answer could be:
- sodium
- osmosis
- hypertonic
- protein
- osmotic pressure
- oncotic pressure
- total body water
- intracellular fluid volume
- glucose
- urea
- water
- concentration
- high venous pressure
- ischemia
- 5% dextrose
- or, most likely, one of your foils…
Lectures 12, 13: Sodium Homeostasis
Describe the compartmental localization of Na+ and the effect of step changes in Na+ intake
Describe the sensory mechanisms involved in the control of extracellular fluid volume
Describe the general pattern of Na+ reabsorption by the nephron
Understand pressure natriuresis, tubuloglomerular feedback and glomerulotubular balance
Understand the effects of sympathetic nerve activity, natriuretic peptides, and the renin-angiotensin-aldosterone system on Na+ excretion
See advice for studying under body fluids lecture. In this lecture, my choice for a correct answer could be:
- 135 mE\q/L
- content
- vascular volume
- stretch receptors
- angiotensin II
- positive balance
- cardiac atria
- pressure (in context of natriuresis)
- proximal convoluted tubule
- ~25%
- ~200 mOsm/L
- autoregulation
- tubuloglomerular feedback
- glomerulotubular balance
- interstitial oncotic pressure
- aldosterone
- atrial natriuretic peptide
- norepinephrine
- decreased effective circulating volume
- extracellular volume expansion
- or, most likely, one of your foils…
Lectures 14, 15: Water Balance
•
Explain the concept of free water clearance
Describe the process by which the kidneys excrete a maximally dilute urine
Describe the process by which the kidneys excrete a maximally concentrated urine
Describe the regulation of ADH secretion and its cellular mechanism of action in the collecting duct
Understand some common causes and consequences of too little or too much body water
See advice for studying under body fluids lecture. In this lecture, my choice for a correct answer could be:
- plasma osmolality
- osmoreceptors
- ADH
- diarrhea
- negative free water clearance
- counter current exchange
- countercurrent multiplier
- urinary solute excretion
- proximal tubule
- thin ascending limb
- thick ascending limb
- collecting duct
- inner medullary collecting duct
- urea
- sodium
- glucose
- inulin
- urine osmolality
- urine volume
- or, most likely, one of your foils…
Lecture 16: Potassium Homeostasis
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Describe the effects of plasma [K+] on excitable tissues in general and as viewed on EKG traces
Describe the non-renal mechanism that buffer acute changes in plasma [K+]
Describe the general reabsorption pattern for filtered K+ along the length of the nephron
Discuss the role of each of the following in regulating K excretion
- Plasma [K+]
- Aldosterone
- ADH
- Tubular fluid flow
- Acid-base balance
See advice for studying under body fluids lecture. In this lecture, my choice for a correct answer could be:
- 3.5 mEq/L
- intracellular fluid
- hyperkalemia
- resting membrane potential
- peaked T wave
- insulin
- angiotensin II
- aldosterone
- norepinephrine
- ADH
- fatal hyperkalemia
- cell lysis
- acidemia
- distal nephron
- plasma aldosterone concentration
- adrenal cortex
- principal cells
- distal K+ secretion
- or, most likely, one of your foils…
Lectures 17, 18: Acid-Base
•
Know the normal values for plasma pH, [HCO3-] and PCO2
Describe the role of the kidneys in excreting the daily load of acid
Discuss the body buffer systems and the rate at which they respond
Compare and contrast the mechanisms for reabsorption of bicarbonate by the proximal tubule and collecting duct
Describe the roles of glutamine and phosphate ion in the kidney with respect to acid-base balance
Describe the calculation of net acid excretion
•
Use the Henderson-Hasselbach equation to explain the roles of the kidneys and lungs in acid-base regulation and compensation
Define the anion gap
List some common causes and consequences of the 4 simple acid-base disorders
See advice for studying under body fluids lecture. In this lecture, my choice for a correct answer could be:
- fixed
- 6.1
- 24 mEq/L
- log 20
- buffer
- potassium
- lungs
- kidneys
- bicarbonate
- Na+-H+ antiporter
- -intercalated cell
- phosphate
- titratable acid
- ammonia
- glutamine
- metabolic acidosis
- compensation
- correction
- anion gap
- or, most likely, one of your foils…