Activation of ion channels by lysylbradykinin in the HCA-7 colony 29 human adenocarcinoma cell line.
1. The patch-clamp technique, both cell attached and inside-out patches, was used to examine the effects of lysylbradykinin (LBK) and A23187 on ion channels in cultured Colony 29 epithelial cells derived from a human adenocarcinoma. 2. LBK and A23187 applied directly to the intact cell stimulated the opening of a number of types of ion channel including Ca(2+)-activated K+ channels. 3. By use of inside-out patches, anion channels could be stimulated to open by application of protein kinase A and ATP to the cytosolic surface. Ca(2+)-activated K+ channels were also identified in isolated membrane patches. 4. The results suggest that the anion secretion which is stimulated by LBK is a complex event, involving the activation of a number of different types of ion channel, and that part of the response is the result of hyperpolarization of the cell by activation of Ca(2+)-activated K+ channels. From the data presented in this and the accompanying papers it appears that the Ca(2+)-sensitive K+ channels would be equally effective in either the apical or basolateral membranes.
Henderson
R M
RM
Department of Pharmacology, University of Cambridge.
Cuthbert
A W
AW
D000230:Adenocarcinoma; D000262:Adenylyl Cyclases / Q000187:drug effects*; D000001:Calcimycin / Q000494:pharmacology*; D005576:Colforsin / Q000494:pharmacology*; D003110:Colonic Neoplasms; D004558:Electric Stimulation; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D007473:Ion Channels / Q000737:chemistry / Q000187:drug effects*; D007609:Kallidin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D007473:Ion Channels; D005576:Colforsin; D007609:Kallidin; D000001:Calcimycin; D000262:Adenylyl Cyclases