Term
| What is the primary solute in extracellular fluid? |
|
Definition
|
|
Term
| If you regulate Na, then u are also regulating what? |
|
Definition
| Plasma volume (direct result) |
|
|
Term
| How is Na filtered at the glomerulus? |
|
Definition
|
|
Term
| Does Na undergo reabsorption? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| How can u regulate plasma Na levels? |
|
Definition
|
|
Term
| Na in the renal tubule undergoes ____ absorption |
|
Definition
|
|
Term
| What is active transport driven by? |
|
Definition
|
|
Term
| Where are the ATPase pumps located in kidneys? |
|
Definition
| Basolateral membranes of renal tubular cells |
|
|
Term
| [ ] of na in proximal tubule =extracellular fluid [ ] sets up [ ]gradient favoring what? |
|
Definition
| Movement of Na from rtl into rtc (intracellular Na is low) |
|
|
Term
| Movement of Na into rtc across the apical is ______(active/passive)? |
|
Definition
|
|
Term
| Overall transcellular process of reabsorption is active |
|
Definition
|
|
Term
| How much Na is reabsorbed in the proximal tubule? |
|
Definition
|
|
Term
| how is the entry of Na into the rtc possible? |
|
Definition
| Carriers that are coupled to movement of other solute molecules |
|
|
Term
| Passive diffusion of Na down its []gradient is coupled to what? |
|
Definition
| Movement of other solute molecules (2ndary active transport) |
|
|
Term
| Secondary active transport forms |
|
Definition
| Co-transport seen with glucose and amino acids |
|
|
Term
| How much Na is reabsorbed in the loop of henle? |
|
Definition
|
|
Term
| how much Na is reabsorbed in Distal tubule and collecting ducts? |
|
Definition
|
|
Term
| Na is actively transported out of what membrane? |
|
Definition
|
|
Term
| In the distal tubule Na crosses the apical membrane via |
|
Definition
| Co-transport with Cl- ions |
|
|
Term
| What is the site for regulation of Na reaborption? |
|
Definition
|
|
Term
| Binding of aldosterone to principal cells increases number of open Na and K channels in the APICAL membrane by: |
|
Definition
|
|
Term
| Binding of principal cells stimulates synthesis ofNa/k atpase pumps in basolateral membranes |
|
Definition
| If aldosterone affects Na it has to affect ___ |
|
|
Term
| What is the most important regulator of aldosterone secretion? |
|
Definition
| Renin-angiotensin-aldosterone system |
|
|
Term
|
Definition
| Granular cells that secrete renin |
|
|
Term
|
Definition
| Created in liver and circulates in plasma. |
|
|
Term
| When Angiotensin I encounters ACE (Angiotensin converting enzyme)= |
|
Definition
|
|
Term
| What are the actions of Angiotensin II? |
|
Definition
|
|
Term
| RAAS acts to do what to blood pressure? |
|
Definition
|
|
Term
| What is the primary stimulus for renin release? |
|
Definition
| Decrease in blood pressure |
|
|
Term
| If blood pressure decreases, what is stimulated for secretion? |
|
Definition
|
|
Term
| A Drop in MAP will activate what reflex? |
|
Definition
|
|
Term
| An activated baroreceptor will activate what system? |
|
Definition
| Sympathetic nervous system |
|
|
Term
| “renal baroreceptors” are located where and do what? |
|
Definition
| Afferent arterioles and cause secretion of renin. |
|
|
Term
|
Definition
| Reduced glomerular filtration rate |
|
|
Term
| If you have a reduced glomerular filtration rate what happens? |
|
Definition
| Decrease in the amount of Na that passes through the distal tubule where it is monitored by the macula densa |
|
|
Term
| If there is a decrease in Na and noted by the macula densa, what does the macula densa signal to secrete renin? |
|
Definition
|
|
Term
|
Definition
| Secreted by cells in the atria in response to stretch |
|
|
Term
|
Definition
| Increase in GFR by dilating |
|
|
Term
| What is the primary determinant of resting membrane potential in excitable cells? Must also be tightly regulated? |
|
Definition
|
|
Term
| K+ is freely filtered at the glomerulus? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Where is the majority of K+ reabsorbed? |
|
Definition
|
|
Term
| Can K+ pass through leaky tight junctions in proximal tubule? |
|
Definition
|
|
Term
| All K that enters preitubular cells in the ___-tubule exits via ____ membrane? |
|
Definition
|
|
Term
| Where does the regulation of K+ occur? |
|
Definition
|
|
Term
| K channels are only present on ____ membrane in the distal tubule? |
|
Definition
|
|
Term
| Aldosterone’s effect on K+ |
|
Definition
| Increases Na/K pumps on basolateral membrane |
|
|
Term
| What cells secrete aldosterone? |
|
Definition
| Adrenal cortex cells in the zona glomerulosa |
|
|
Term
| If you have elevated K+ level in plasma, what happens to the secretion of aldosterone? |
|
Definition
| Increases the secretion of aldosterona and = increase in K+ secretion by the cells |
|
|
Term
|
Definition
| Freely filtered (occurs distally) |
|
|
Term
| How do kidneys regulate amoung of water in plasma? |
|
Definition
| Adjusting reabsorption of water |
|
|
Term
| Is water reabsorption passive or active process? |
|
Definition
|
|
Term
| If water reabsorption is passive, what is the process for the reabsorption of solutes? |
|
Definition
|
|
Term
| The osmotic gradient established by reabsorption of solute increases ____ of the peritubular fluid |
|
Definition
|
|
Term
| What establishes the medullary osmotic gradient? |
|
Definition
| Loops of henle of juxtagloerular nephrons |
|
|
Term
| What drives the reabsorption of water? |
|
Definition
| Medullary osmotic gradient in the collecting ducts |
|
|
Term
| Countercurrent multiplier |
|
Definition
| Sum of permeability characteristics of ascending and descending limbs of loop of henle |
|
|
Term
| Is the descending limb permeable or impermeable to water? And inmpermeable or permeable to Na/Cl/K? |
|
Definition
|
|
Term
| Is the ascending limb permeable to both Na/Cl/K and water? |
|
Definition
|
|
Term
| The fluid that enters the distal tubule…is it hypoosmotic? Hyperosmotic? Isoosmotic? |
|
Definition
| HYPOOSMOTIC (100-200mOsm) |
|
|
Term
|
Definition
| Arrangement of blood vessels in renal medulla that allows the []gradient to be maintained. |
|
|
Term
|
Definition
| Channels in cell membranes which allow water to flow through |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Permeability of late distal tubule to water |
|
|
Term
|
Definition
| Stimulates insertion of aquaporins into apical membrane |
|
|
Term
| If you have a High level of ADH what happens to the aquaporins? And water reabsorption? What about urine output? |
|
Definition
| Increases, increases. Urine output is low |
|
|
Term
|
Definition
| Little water reabsorption, high urine output |
|
|
Term
| What 2 things regulate ADH secretion? |
|
Definition
|
|
Term
| What is the stronges stimuli for ADH secreation? |
|
Definition
| Increase in plasma osmolarity |
|
|
Term
| what kind of receptors in the hypothalamus monitor osmolarity? |
|
Definition
|
|
Term
| If you have decreased BP/blood volume= |
|
Definition
| Less activity from baroreceptors= increase in ADH |
|
|
Term
| What is Diabetes insipidus |
|
Definition
| Deficiency in ADH= excessive urine output |
|
|
Term
| What converts CO2 to carbonic acid? |
|
Definition
|
|
Term
| What is the normal pH of the blood? |
|
Definition
|
|
Term
|
Definition
| Respiratory system and Kidney |
|
|
Term
| In order to allow normal body function...pH must be _______ regulated |
|
Definition
|
|
Term
| Acidosis occurs when pH levels hit < |
|
Definition
|
|
Term
| Alkalosis occurs whe pH levels hit > |
|
Definition
|
|
Term
| What are 2 buffering systems? |
|
Definition
1. Hemoglobin 2. Bicarbonate |
|
|
Term
| In the lungs, the role of Hb is to |
|
Definition
| unload H+ (which is exhaled as CO2) and loads O2 |
|
|
Term
| What is the Henderson-Hasselbalch Equation? |
|
Definition
| pH=6.1 + log [HCO3-]/[CO2] |
|
|
Term
| In order to maintain ration of Bicarbonate the ratio of CO2 must be 20:1 must be maintained in order to keep _________ |
|
Definition
| Normal arterial pH of 7.4 |
|
|
Term
What primarily reglates HCO3-? |
|
Definition
|
|
Term
| What is respiratory acidosis |
|
Definition
inc in acidity of blood due to inc in Pco2. = HYPOVENTILATION |
|
|
Term
|
Definition
dec. in acidity of blood de to dec in Pco2. =hyperventilation |
|
|
Term
| What is the function of the kidney? |
|
Definition
Process plasma. involves removal and addition of substances from it. |
|
|
Term
| Process of removal/addition of substances from plasma include.... |
|
Definition
regulation of: - plasma water volume
- plasma osmolarity
- inorganic ion [] of plasma
- excretion of metabolic wastes (urea, creatine)
- excretion of foreign substances
- glucogenesis during fasting
- secondary endocrine organ (renin, erythrooetin)
|
|
|
Term
| Where are the kidneys located? |
|
Definition
|
|
Term
| Kidney is made up of 2 parts: |
|
Definition
Outer Cortex Inner medulla |
|
|
Term
What is the functional unit of kidney? |
|
Definition
| nephron ( this is what actually does the work) |
|
|
Term
| How many nephrons are there per kidney? |
|
Definition
|
|
Term
| Vascular elements of a nephron: |
|
Definition
- Afferent arteriole
- Glomerulus
- Efferent arteriole
- Peritubular capillaries
- Vasa recta
|
|
|
Term
| Tubular elements of a nephron |
|
Definition
Bowman's capsule Proximal Tubule Loop of Henle Distal Tubule Collecting ducts Renal pelvis |
|
|
Term
| Where in the kidney do most nephrons reside? |
|
Definition
|
|
Term
| What is a cortical nephron? |
|
Definition
| nephrons that reside in the cortex of the kidney |
|
|
Term
| what are Juxtamedullary nephrons? |
|
Definition
| subset of nephrons located adjacent to the medulla Loops of henle of these ephrons extend down into _____(Renal medulla) |
|
|
Term
3 processes occur in the kidney |
|
Definition
Filtration Reabsorption Secretion |
|
|
Term
|
Definition
| movement of fluid from the blood to the lumen of tubule |
|
|
Term
|
Definition
| movement of material from the tubular lumen back into the blood (peritubular capillaries) |
|
|
Term
| What happens during secretion? |
|
Definition
| Selective movement of molecules from the blood into the tubular lumen. |
|
|
Term
|
Definition
| occurs when plasma flows through glomerular capillaries and the fluid passes into Bowman's space. |
|
|
Term
| When the filtrate contains the same concentration of electrolys, it means that it is _-____ to plasma. |
|
Definition
|
|
Term
| Where does Filtration occur? |
|
Definition
|
|
Term
| The Renal Corpuscle consists of? |
|
Definition
| Glomerus and bowman's capsule |
|
|
Term
|
Definition
Glomerular Capillay endothelium Basement membrane Epithelium of Bowman's capsule |
|
|
Term
| Glomerular capillary endothelium |
|
Definition
Fenestrated capillaries w/ large pores Contains (-) charged surface proteins which repel (-) charged plasma proteins |
|
|
Term
|
Definition
barrier layer of filtration. (-) charged glycoproteins Collagen matrix wchich acts like a sieve |
|
|
Term
| Epithelium of Bowman's capsule |
|
Definition
|
|
Term
|
Definition
Specialized cells that wrap around capillaries and making filtration slits. Also have contractile fibers |
|
|
Term
|
Definition
Cells that lie betw/ and around glomerular capillaries. Secrete cytokines. have contractile filaments that allow them to alter blood flow through capillaries. |
|
|
Term
| Forces involved in filtration |
|
Definition
|
|
Term
| Forces favoring filtration from glomerular capillaries |
|
Definition
| Hydrostatic Pressure of blood. PGC |
|
|
Term
| Hydrostatic pressure of blood in capillaries |
|
Definition
Avg pressure = 55 mmHg (higher than systemic capillaries) DOES NOT DECLINE as blood travels down the capillary. |
|
|
Term
| Colloid osmotic pressure of bowman's space (PiBS) |
|
Definition
|
|
Term
| forces opposing filtration |
|
Definition
Colloid osmotic pressure inside capillary (PiGC) Hydrostatic pressure of fluid in Bowman's space (PBS) |
|
|
Term
| Colloid osmotic pressure inside capillary |
|
Definition
created by protein mainly albumin. b/c fluid leavin is great, osmotic pressure increases as blood travels through. |
|
|
Term
|
Definition
NFP= PGC-PiGC-PBS *Typical NFP = 10 mmHg |
|
|
Term
| What kind of capillaries does the glomerus have? |
|
Definition
|
|
Term
| What is our plasma Volume? |
|
Definition
|
|
Term
| Body filters entire plasma volume every ___minutes? |
|
Definition
|
|
Term
| Filtration is influenced by? |
|
Definition
Net filtration pressures Filtration Coefficient |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| MAP and Renal blood flow influence ____ ____ |
|
Definition
|
|
Term
| what maintains GFR relatively ocnstant inspite of variations in MAP? |
|
Definition
|
|
Term
|
Definition
| Glomerular Filtration Rate |
|
|
Term
| TUbuloglomueraular feedback, helps with intrinsic regulation of GFR how? |
|
Definition
Fluid flowing though the distal tubule affects GFR Inc flow is sensed by macula densa. therefore caula releases paracrine agents that cause vasoconstriction and leads to decreased filtration. |
|
|
Term
|
Definition
| specialized cells in distal tubule. release paracrine agents=vasoconstriction of afferent arteriole. |
|
|
Term
| Intrinsic regulation of GFR |
|
Definition
Myogenic responsee Tubuloglomerular Feedback |
|
|
Term
| Extrinsic regulation of GFR |
|
Definition
- Sympathetic input
- hormones
|
|
|
Term
| What causes vasoconstriction of the afferent arteriole and decreases capillary hydrostatic pressure leading to decrease in GFR? |
|
Definition
| sympathetic innervation of the afferent arteriole |
|
|
Term
| what hormones help regulate GFR |
|
Definition
Angiotensin II (vasoconstriction) Atrial Natriuretic Peptide (vasodilator) |
|
|
Term
|
Definition
| movement of material from the tubular lumen, back into the palsma flowing through the peritubular capillaries. |
|
|
Term
| where does most reabsorption occur? |
|
Definition
|
|
Term
| where does finely regulated reabsorption occur? |
|
Definition
| distal segments of the nephron |
|
|
Term
| how much fluid is approx. filtered each day? |
|
Definition
|
|
Term
| how much fluid is excreted per day by the body? |
|
Definition
|
|
Term
| what % of fluid filtered from the plasma is reabsorbed? |
|
Definition
|
|
Term
| what 2 general means by which reabsorption occur? |
|
Definition
by mediated transport by diffusion |
|
|
Term
| what is transcellular epithelial transport? and what undergoes it? |
|
Definition
movement of substances across the luminal membrane followed by moevement across the basolateral membrane. substances reabsorbed by mediated transport undergo it. |
|
|
Term
| transcellular transport requires what? |
|
Definition
| active transport (primary or secondary) across 1 membrane and passive transport (diffucsion or facilitated diffusion) across the other. |
|
|
Term
|
Definition
| Transport systems that use a mediator (carrier) have no limits to the amount of material they can transport per unit time |
|
|
Term
| where is transport maximum seen? |
|
Definition
|
|
Term
| if one's plasma glucose gets too high like in ppl with diabetes, what can be exceeded resulting in some glucose being exfcreted in urine? |
|
Definition
|
|
Term
|
Definition
| excretion of glucose in urine. |
|
|
Term
| where does free diffusion occur in reabsorption? |
|
Definition
| palsma membrane of the renal tubule and the capillary endothelium |
|
|
Term
| in order to have diffusion work the [] of the substance must be < or > in the tubular lumen? |
|
Definition
|
|
Term
| any material that is reabsorbed by diffusion is said to |
|
Definition
| Follow water reabsorption |
|
|
Term
| water reabsorption depends on? (based on differences in osmolarity) |
|
Definition
|
|
Term
| as solutes are reabsorbed by ACTIVE transport in mediated transport, what happens to the tubular osmolarity and the osmolarity of plasma? |
|
Definition
| tubular osmolarity is decreased, and osmolarity of plasma is increased. |
|
|
Term
| water diffuses from an area of low osmolarity (tubular lumen) to an area of higher osmolarity (peritubular fluid)? |
|
Definition
|
|
Term
| water follows active? passive? reabsorption of solute? |
|
Definition
|
|
Term
| water follows active reabsorption of solute only if water can permeate the tubule epithelium? |
|
Definition
|
|
Term
| Are there any areas of the renal tubule that are impermeable to water? |
|
Definition
|
|
Term
|
Definition
| movement of substances from the peritubular capillaries into the tubular lumen |
|
|
Term
| what are the barriers in secretion? |
|
Definition
| same as in reabsorption but backwards. |
|
|
Term
| what is the purpose of secretion? |
|
Definition
| increase efficiency of kidney in disposing of substances at a higher rate than the filtered load. |
|
|
Term
| Regional specialization of renal tubules |
|
Definition
proximal tubule distal tubule and collecting ducts |
|
|
Term
|
Definition
made of epithelium modified for efficient reabsorption |
|
|
Term
|
Definition
| highly folded apical membranes that increase surface area of proxima tubule. |
|
|
Term
| how much glucose is reabsorbed in the proxiam tubule? |
|
Definition
|
|
Term
| how much filtered solutes and water are abosrbed in the proximal tubule? |
|
Definition
|
|
Term
|
Definition
many mitochondria (provides many ATP) tight junctions that are leaky |
|
|
Term
|
Definition
| tight junctions found in proximal tubule. allow paracellular transport. |
|
|
Term
| what is required for active transport? (energy wise?) |
|
Definition
| ATP. provided by the mitochondria in the proximal tubule. |
|
|
Term
| Is the reabsorption of solutes and water regulated in the proximal tubule? |
|
Definition
|
|
Term
| cells in what renal tubul;e are specialized to allow regulation of reabsorption and secretion? |
|
Definition
| Distal tubule and collecting ducts. |
|
|
Term
| High brush border occurs where? |
|
Definition
|
|
Term
| minimal brush border occurs where? |
|
Definition
| Distal tubule and collecting ducts |
|
|
Term
| Tight junctions in distal tubule and collecting ducts |
|
Definition
| Tighter compared to proximal tubule. |
|
|
Term
| cells in the distal and collecting ducts with receptors for __________. can regulate water and solute handling? |
|
Definition
|
|
Term
|
Definition
| quantity of a solute filtered per unit time |
|
|
Term
| Freely filterable solutes |
|
Definition
| solutes that are small and readily make it through the filtration barrier |
|
|
Term
| [] of freely filterable substances in Bowman's capsule is identical to the plasma [] |
|
Definition
|
|
Term
| Equation for Filtered Load |
|
Definition
| Filtered Load= P[S] x GFR |
|
|
Term
| Clearance (Renal Plasma Clearance) |
|
Definition
"virtual" measurement of the volume of plasma from which a substance will be completely cleared in one minute by excretion in the urine. expressed in VOLUME OF PLASMA PER UNIT TIME |
|
|
Term
|
Definition
Clearance= [urine [] of S]x[urine volume per unit time] ------------------------------------------ Plasma [] of S |
|
|
Term
|
Definition
Breakdown product from muscle creatine. produced @ constant rate freely filtered by glomerulus and small amnt. of secretion. |
|
|
Term
| where is Creatinine clearance used? |
|
Definition
| clinical settings to estimate GFR |
|
|
