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: beta2 ( - / - ) mice displayed increased susceptibility to seizures , as indicated by reduced latency and threshold for pilocarpine - induced seizures , but seemed normal in other neurological tests .
### Output Text:
beta2 ( - / - ) mice displayed increased susceptibility to seizures , as indicated by reduced latency and threshold for <span class="chemical">pilocarpine</span> - induced seizures , but seemed normal in other neurological tests . 