changing job with permanent visa status

All depends on how you obtained original permanent visa. Would suggest you look at the Ministry of Labor site as to such. Not sure if you need another labor contract from an employer.

Texan brazil,

I obtained my original permanent visa through an extension of temporary visa when working for the same company with a renewed labor contract. Would this be able to help you giving me a better insight of what the possibilities are to change from employer?

I looked at the ministry of labor and policia federal websites, but could not find anything related to my question.

I would not like to give you an incorrect answer. You received it via an employer and now leaving that employer?  If permanent resident was given based on the work permit, you may need to do the process again. If there is a consulate near you or can get an email address, they may be of more help than I. Or ne employer may be able to help.
Do not know if the employer would report anything. If based on the former employer, which had to "jump through the hoops", and they advised you are no longer working, it may trigger something in the system.