I saw it in the early 90s. I remember a scene where a man was hiding in a closet with white doors with air gaps. When the man stepped out of the closet, he had his pointing finger made out of metal with a hole. This metal finger was a gun.
Another scene from this movie is where some kind of ship is being shrinked (by 1000 times) and entered some pink/orange tunnels (maybe a human body..).
“Innerspace”(1987)?
Here is the trailer.
https://youtu.be/7kQDIosuZuo
Here is a photo of the villain who had the gun/finger, I think.
https://goo.gl/images/pqiEBg
Yes! It was “Innerspace”(1987).
Thank you memoniacer.
Solved!