TABLE II.

Increase in BK_Ca Channel Activity by Different Natural Bile Acids and Synthetic Analogues in Smooth Muscle Cells Freshly Isolated from Rabbit Main Pulmonary Artery and Gallbladder, Recorded in Either Cell-attached (C-A) or Inside-out (I-O) Patches

	C-A	I-O
Main pulmonary artery
Lithocholic acid	6/6	4/4
Taurolithocholic acid	0/3	2/2
Gallbladder
Deoxycholic acid	2/2	2/2

Results are expressed as the ratio of the number of positive results to the number of patches tested. Lithocholic acid and its tauroconjugate were applied at 100-μM concentrations in the puffer pipette to pulmonary artery cells, and deoxycholic acid was applied at a concentration of 3 mM in the puffer pipette to gallbladder cells. Compounds were prepared from stock solutions and diluted in bath solution to the final concentration (materials and methods). Solvents used to prepare the stock solutions were equally diluted and applied onto the patches (controls). The DMSO-ethanol dilution (<0.03%/<0.3% vol/vol) did not noticeably modify channel activity in pulmonary artery cells (C-A, 0/3; I-O, 0/3). Likewise, the DMSO-ethanol dilution (<0.9%/<9% vol/vol) did not noticeably modify channel activity in gallbladder cells (C-A, 0/2; I-O, 0/2).