How to execute stored procedures in drupal ?

I have a website which does lot of work on financial data. It involves operations on large volumes of data most of the time. Hence I find it useful to do those operations in mysql stored procedures. I have stored procedures in my database. I want to know how can I execute stored procedures in drupal? Is there any good method to execute stored procedures in drupal? How drupal handles stored procedures in general? Or we just have to use the PHP to execute stored procedures?

Thanks in advance