How to set additional parameters in http service

All,

I am trying to make a call to rest api url.

I am using the http service to pass the url and string data.

The url format is like this:

https://text.abc.com/2245634634554062/data-v1-cycle-In/?Action=SendMessage&MessageBody=<payload_string>

This works in the IE browser but when I put this in http url. It says illegal character. Do I need to pass the additional parameters like the Action and MessageBody seperately. If yes, How do I do it?

I used args document but was not successful.

Please help!
Thanks again.