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 this study , the hypothesis was tested that there is a sexual dimorphism in HS - induced upregulation of intrarenal angiotensinogen mediated by testosterone that also causes increases in BP and renal injury .
### Output Text:
In this study , the hypothesis was tested that there is a sexual dimorphism in HS - induced upregulation of intrarenal angiotensinogen mediated by <span class="chemical">testosterone</span> that also causes increases in BP and renal injury . 