What Is The Name Of The “Thing” That Innervates M1 MAChR In Parts Of The Cortical Membranes And In The Hypothalamus Membrane

  

What is the name of the “thing” that innervates M1 mAChR in parts of the cortical membranes and in the hypothalamus membranes? I know the “thing” secretes acetylcholine but I can’t figure out what it is called.