Glomerular Filtration

Flashcards covering key concepts and vocabulary from glomerular filtration, including GFR, auto-regulation, and clearance calculations.

Glomerular Filtrate

The fluid produced by the kidneys that is filtered from the blood through the glomerulus, composed mainly of water and small solutes.

Glomerular Filtration Rate (GFR)

The rate at which blood is filtered through the glomeruli of the kidney, typically measured in milliliters per minute.

Starling's Forces

The forces that determine the movement of fluid across capillary membranes, including hydrostatic and oncotic pressures.

Renal Plasma Flow (RPF)

The volume of plasma that flows through the kidneys per unit time, which is crucial for determining GFR.

Filtration Fraction (FF)

The ratio of GFR to RPF, indicating the proportion of plasma that is filtered through the glomeruli.

Afferent Arteriole (AA)

The blood vessel that carries blood to the glomerulus, which can constrict or dilate to regulate GFR.

Efferent Arteriole (EA)

The blood vessel that carries blood away from the glomerulus, which also plays a role in regulating GFR through constriction.

Auto-regulation

The kidney's ability to maintain a relatively constant GFR despite fluctuations in systemic blood pressure.

Angiotensin II (AII)

A peptide hormone that causes constriction of the efferent arteriole and helps maintain GFR during low blood pressure.

Clearance

The volume of plasma from which a substance is completely removed by the kidneys per unit time.

Ideal Filtration Marker

A substance that is freely filtered by the glomerulus and neither secreted nor reabsorbed, such as inulin.

Creatinine Clearance

A test used to estimate GFR, although it slightly overestimates GFR due to some tubular secretion.

Prostaglandins

Hormones that can cause dilation of the afferent arteriole, helping to maintain GFR during stress.

Net Filtration Pressure (PUF)

The difference between hydrostatic pressure and oncotic pressure that determines the net movement of fluid across the glomerular membrane.

Ultrafiltration Coefficient (Kf)

A measure that reflects the membrane permeability and surface area available for filtration in the glomerulus.