[Natural antiallergenic factors in bile]

Two groups of substances having an antihistaminic activity were found on purifying bovine bile. It has already been found that bile acids inhibit contraction of guinea pig ileum; another principle has been isolated which is one thousand times more active than the bile acids; this (these) substance(s)--SAN (" substance antiallergique naturelle ")--seems to have more inhibitory effect on smooth muscle contraction induced by SRSA than histamine, acetylcholine, bradikinin and serotonin. SAN is also able to inhibit the Schultz-Dale reaction. These findings indicate that SAN could be a possible antiallergic agent.