27521
Concerning brimonidine hypotensive action , an additional IOP reduction of 29 . 26 +/- 5 . 21 % or 39 . 07 +/- 5 . 81 % ( p < 0 . 001 ) was observed in rabbits pretreated with melatonin or 5 - MCA - NAT when compared with animals treated with brimonidine alone for 24 hours .
 Chemical: brimonidine; Chemical: melatonin; Chemical: 5 - MCA - NAT; Chemical: brimonidine
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: brimonidine; Chemical: melatonin; Chemical: 5 - MCA - NAT; Chemical: brimonidine