Body Compartments And Drug Movement A Flashcards
What is a body compartment?
Locations separated by physical barrier, usually refers to fluids
What are cavities?
Spaces that contain organs and are surrounded by a thin layer of fluid.
What is a lumen?
Channels within organs or tissues, filled with or lined by fluid.
What does the endothelial lumen cover?
Heart, blood vessels and lymphatics
What does the epithelial lumen cover?
What ever comes in contact with the external environment.
Respiratory tract, gut, urinary and reproductive tract and sweat ducts
What are the percentages for all the fluids within the body compartments
Intracellular-fluid = 67%
Interstitial fluid = 26%
Plasma + other fluid =7%
what does extracellular fluid contain?
Interstitial fluid
Plasma
Other fluids
What is interstitial fluid?
A thin layer of fluid that surrounds the body’s cells
Give examples of body cavities:
- Thoracic cavity
- Abdominal cavity
- Pelvic cavity
- Pleural cavity
Rough estimates of pH for;
Extracellular and intracellular fluid Mouth Stomach Duodenum Small intestine Colon Urine
Extracellular and intracellular fluid 7.35-7.45 Mouth 6.2-7.2 Stomach 1.0-3.0 Duodenum 4.8-8.2 Small intestine 7.5-8.0 Colon 7.0-7.5 Urine range = 4.6 8.0 average = 6.0
What is the serous membrane?
Membrane which lines the internal body cavities and organs.
What are the barriers between compartments, in order?
Lumen Epithelium Endothelium Cavity Organ Cell lipid membrane
Name the 3 main epithelium types:
Squamous (flat)
Cuboidal
Columnar (thin & tall)
What are the two types of drug movement across the epithelium of endothelium ?
Paracellular movement
Transcellular movement
What are intracellular junctions?
Specialised regions of contact between plasma membranes of adjacent cells
What is the difference between simple and stratified epithelium?
Simple tissue is one layer
Stratified is multi-layered
What are the three movements of drugs across a cell membrane?
Diffusion through a lipid bilayer
Active transport
Pinocytosis
What is transcellular movement?
Drugs move across the epithelial through intracellular transfer from the lumen into the blood stream.
What is paracellular movement?
Drugs move between cells through intracellular junctions.
What is intracellular fluid?
It contains all fluids enclosed in cells by their plasma membranes