Oxygenated 3 in de-oxygenated channels? (6)
I believe the answer is:
venous
'in de-oxygenated channels?' is the definition.
(in veins, vessels with de-oxygenated blood)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for venous that I've seen before include "Of blood tubes" , "like a carrier of blood" , "through certain tubes" , "Performing the function of veins" , "Relating to blood vessels" .)