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: The prolonged depletion of dopamine in the striatum in mice , given multiple injections of methamphetamine , was also antagonized dose - dependently and completely by LY274614 .
### Output Text:
The prolonged depletion of <span class="chemical">dopamine</span> in the striatum in mice , given multiple injections of <span class="chemical">methamphetamine</span> , was also antagonized dose - dependently and completely by <span class="chemical">LY274614</span> . 