The document describes the sympathetic nervous system and its neurotransmitters. It discusses how acetylcholine acts as the preganglionic neurotransmitter while norepinephrine, epinephrine, and dopamine act as postganglionic neurotransmitters. It also describes the effects of these neurotransmitters on adrenergic receptors, including their effects on cardiovascular function. Key drugs that act on the sympathetic nervous system are also mentioned.