In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: A second group of rats was treated identically and , in addition , received an infusion of saralasin ( a competitive inhibitor of angiotensin II ) throughout the experimental period .
### Output Text:
A second group of rats was treated identically and , in addition , received an infusion of <span class="chemical">saralasin</span> ( a competitive inhibitor of <span class="chemical">angiotensin II</span> ) throughout the experimental period . 