You will be given a definition of a task first, then some input of the task.
In this task, you are given a sentence. You are expected to write the name of the organism substances in the body mentioned in the input. Although there might be several correct answers, you need to write one of them.

The agonism of 5 - HT1A receptors , negatively coupled to cAMP , reduces IOP by decreasing the production of aqueous humor , like beta - receptor antagonists which , diminishing the content of cAMP at the postjunctional site , lowers the aqueous humor secretion with a consequent decrease in IOP [ 98 ] .
Output:
humor