Human Physio Renal function and fluid balance

extracellular, blood pressure

Regulation of ______ fluid volume & ______

plasma osmolarity, ion balance

Regulation of ______
Maintenance of ________

pH, H+, HCO3-

Homeostatic regulation of ____
remove or conserve either ____ or ______ (bicarbonate ions) as needed

Excretion of waste

removes metabolic wastes dissolved in plasma e.g. uric acid and creatine

Secretion of hormones and enzymes

erythropoietin (RBC production), renin (sodium balance and BP homeostasis) & vit D conversion to control Ca2+ balance

Renal corpuscle

________ filters blood plasma
Glomerulus capillary network

Glomerular (Bowman’s) capsule double walled up surrounding glomerulus

Proximal, loop of henle, Distal

Renal tubule filtered fluid passes into:

_____ convoluted tubule

descending, ________ (nephron loop) and ascending

______ convoluted tubule

Urinary excretion

_______ of substance depends on its filtration, reabsorption and secretion.

Glomerular, Basal, Epithelium

Filtration barriers:
_______ capillary endothelium

________ lamina

________ of Bowman’s capsule- podocytes

Hydrostatic/blood pressure

pressure of flowing blood in glomerular capillaries

favors movement of filtrate into Bowman’s capsule

Colloid osmotiv pressure

plasma proteins entering capsule create a gradient that favors movement back into capillaries

Hydrostatic fluid pressure

in fluid up in enclosed Bowman’s capsule

creates a gradient that favors movement back into capillaries

Glomerular filtration rate (GFR)

volume of fluid that filters into Bowman’s capsule per unit time

pressure, surface area, permeability

Factors influencing GFP:
Net filtration ______

_______ of glomerular capillaries

________ between capillary & Bowman’s capsule

Myogenic response

Intrinsic ability of vascular smooth muscle to respond to pressure changes
↑afferent arteriole resistance →↓GFR

↑efferent arteriole resistance → ↑GFR

Tubuloglomerular feedback

Paracrine control through loop of Henle

resistance, filtration coefficient

Hormones and autonomic neurons:

By changing _____ in arterioles

By altering the ______

Angiotensin II - vasoconstrictor
Prostaglandins - vasodilators

Reabsorption

movement of filtered solutes and water from lumen of tubule back into plasma

takes places in proximal tubule and distal segment of nephrons

active, electrochemical, osmotically

Principles governing tubular reabsorption of solutes & water:

_____ transport to create concentration of ______ gradient

water ______ follow solutes

Transepithelial transport (passing through cells)

substances cross both apical and basolateral membrane

Paracellular pathway (passing around cells)

substances pass through junction between two adjacent cells

Secretion

Transfer of molecules from extracellular fluid into lumen of nephron

dependent on membrane transport proteins to move organic compounds

against, K+, H+, homeostatic regulation

active process move substrates ____ concentration gradient & use secondary active transport to move into lumen

secretion of ___ and ___ is important in ___________

excretion

enables nephron to enhance excretion of substance:
adds to substances collected during filtration, making _______ more effective

Plasma proteins

________ entering capsule create a gradient that favors movement back into capillaries.

urinary loss

In response to diet intake, ________ helps to maintain proper levels of Na+, K+, Ca2+ ions.

Kidneys

________ can not replenish lost water; only preserve or get rid of excess amounts.

Urinary excretion of substance

________ depends on its filtration, reabsorption and secretion.

aldosterone release

Angiotensis II (ANG II) is the usual signal controlling ________ from the adrenal cortex

RAS pathway

The ________ begins when afferent arterioles secrete renin.

angiotensinogen, ANG II

Renin converts inactive ______, into angiotensis I (ANG I)

ANG I converted into ____ by angiotensis-converting enzyme (ACE)

adrenal gland, Na+

ANG II → _______ → synthesis and release of aldosterone

Aldosterone reabsorb ____ at collecting duct

Renal filtration

________ will stop if there is a major loss causing extremely low blood pressure and blood volume.

ANG II

________ increases blood pressure and inflammation, death of cells in alveoli.

Homeostasis

________ maintains water balance unless there is pathology or an abnormal ingestion of water.

nephron

The ________ is the functional unit of the kidney.

ACE2

When the SARS- CoV- 2 virus binds to ________, it prevents ________ from performing its normal function to regulate ANG II signalling.

Diuretics

________: drugs that promote urine excretion.

Osmolarity

________ of urine measure of how much water is excreted by kidneys.

Osmolarity changes

________ as filtrate flows through nephron.

Angiotensis II

________ (ANG II) is the usual signal controlling aldosterone release from the adrenal cortex.

Autoregulation of glomerular filtration rate

________ takes place over a wide range of blood pressures.

ACE2

________ is present in many cell types and tissues including the lungs, heart, blood vessels, kidneys, liver and gastrointestinal tract.

ACE2

________ is highly abundant on type 2 penumocytes in alveoli.

Epithelium of Bowmans capsule

podocytes

Angiotensin II

vasoconstrictor

Prostaglandins

vasodilators

Diuresis

removal of excess water in urine

diuretics

drugs that promote urine excretion

aquaporins, vasopressin/antidiuretic hormone

water reabsorption process involves adding or removing ______ in apical membrane

depends on secretion of ______ (ADH)

hypothalamus

Vasopressin is secreted by _______

osmolarity, osmoreceptors, pressure, volume

3 stimuli controlling vasopressin secretion:

Plasma osmolarity > 280mOsM
higher the _______, more vasopressin released by posterior pituitary
_______ in hypothalamus detect changes in osmolarity

Blood p_____

Blood v______