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: In control animals and in animals treated acutely with CYP , only small numbers of NOS - IR cells ( 0 . 5 - 0 . 7 cell profiles / sections ) were detected in the L6 - S1 dorsal root ganglia ( DRG ) .
### Output Text:
In control animals and in animals treated acutely with <span class="chemical">CYP</span> , only small numbers of NOS - IR cells ( 0 . 5 - 0 . 7 cell profiles / sections ) were detected in the L6 - S1 dorsal root ganglia ( DRG ) . 