612
Erectile function was assessed 6 weeks following uni - and bilateral injections of 6 - hydroxydopamine in the substantia nigra nucleus of the brain .
 Chemical: 6 - hydroxydopamine
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Chemical: 6 - hydroxydopamine