In this task, you are given a sentence. You are expected to recognize the name of any form of chemical substances. Although there might be several correct answers, you need to write one of them.

[Q]: Relative expression of cholesterol transport-related proteins and inflammation markers through the induction of 7-ketosterol-mediated stress in Caco-2 cells.
[A]: cholesterol


[Q]: A novel membrane sensor for histamine H1-receptor antagonist "fexofenadine".
[A]: histamine


[Q]: Increased Cat3-mediated cationic amino acid transport functionally compensates in Cat1 knockout cell lines.
[A]:
amino acid