Apical plasma membrane vesicles formed from organ donor colon demonstrate Na+ and H+ conductances and Na+/H+ exchange.
Apical plasma membrane vesicles were prepared from human organ donor colon mucosal scrapings. These vesicles were enriched 10-fold in cysteine-sensitive alkaline phosphatase activity compared to starting homogenates, and showed minimal contamination of microsomal, mitochondrial or basolateral membranes. Transport studies using [22Na] uptake into proximal colonic vesicles demonstrated Na+ and H+ conductances, Na+/H+ exchange and amiloride inhibition of Na+ uptake. The isolation of these apical vesicles will permit detailed study of human colonic transport processes.
Harig
J M
JM
Department of Medicine, University of Chicago Hositals & Clinics.
Dudeja
P K
PK
Knaup
S M
SM
Shoshara
J
J
Ramaswamy
K
K
Brasitus
T A
TA
D000584:Amiloride / Q000494:pharmacology; D001693:Biological Transport, Active / Q000187:drug effects; D002352:Carrier Proteins / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D003106:Colon / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D009130:Muscle, Smooth / Q000378:metabolism; D011522:Protons; D012964:Sodium / Q000378:metabolism*; D017923:Sodium-Hydrogen Exchangers; D014019:Tissue Donors
D002352:Carrier Proteins; D011522:Protons; D017923:Sodium-Hydrogen Exchangers; D000584:Amiloride; D012964:Sodium