Different Permissions for Channel and Discussion in channel

Description

It here some way to have different permissions for discussion under Channel ?

Example:

Channel XXX have Users 1,2,3,4,5,6,7,8,9

User 1 starts discussion ich channel XXX and invite users 2,3,4,5
Users 6,7,8,9 are able to read this discussion.

It is somehow possible to make it private discussion for users 1,2,3,4,5 ?
Wanted behavior: 6,7,8,9 are not able to read the discussion, because they are not invited, but still in channel for other discussions or chat.