TASK DEFINITION: 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.
PROBLEM: Inhibition of cardiac voltage-gated sodium channels by grape polyphenols.

SOLUTION: sodium

PROBLEM: Phosphorylation and up-regulation of diacylglycerol kinase gamma via its interaction with protein kinase C gamma.

SOLUTION: diacylglycerol

PROBLEM: Preferential cerebrospinal fluid acetylcholinesterase inhibition by rivastigmine in humans.

SOLUTION:
rivastigmine