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: Fenoldopam is a selective dopamine - 1 ( DA1 ) receptor agonist that causes vasodilatation to the kidney and other organs with DA1 receptors and preserves blood flow to the kidney during induced hypotension .
### Output Text:
Fenoldopam is a selective <span class="chemical">dopamine</span> - 1 ( DA1 ) receptor agonist that causes vasodilatation to the kidney and other organs with DA1 receptors and preserves blood flow to the kidney during induced hypotension . 