2. nicotinic actions (ganglion, skeletal muscle, adrenal medulla NH-R: co-innervation and dominant theory adrenaline release N-R: skeletal muscle contraction2. nicotinic actions (ganglion, skeletal muscle, adrenal medulla) ❖ NN -R: co-innervation and dominant theory adrenaline release ❖ NM -R: skeletal muscle contraction