Neurotransmitter and Receptors
Sympathetic and parasympathetic nerve endings do what?
secrete one of two neurotransmitters
What are the two types of neurotransmitters?
acetylcholine and norepinephrine (or epinephrine)
What are the preganglionic neurons that secrete ACh?
If a neuron secretes NE what kind of neuron is it?
What is key to stimulate a parasympathetic or sympathetic?
what kind of receptors always bind to ACh?
What are the two forms of cholinergic receptor?
Nicotinic receptors and muscarinic receptors
Where can you find nicotinic receptors?
all postganglionic neurons
Where can you find muscarinic receptors?
What is the process of nicotinic receptors?
- ACH binding to nicotinic receptors has an excitatory effect: it results in the direct opening of Na+ channels and the production of action potentials.
What is the process of Muscarinic receptors?
- When ACH binds to muscarinic receptors, the cell’s response is either excitatory or inhibitory, depending on the target tissue.
What are the two major classes of adrenergic receptors?
alpha and beta
What binds to alpha and beta receptors?
Norepinephrine and epinephrine
Where is an adenergic receptor found?
most sympathetic effector organs
What is the process of Adrenergic Receptors?
- NE binding to adrenergic receptor can be either excitatory or inhibitory depending on which subclass of receptor predominates in the target organ.
- Activation of nicotinic receptors is excitatory, whereas activation of muscarinic, alpha, and beta receptors is either excitatory or inhibitory.
sympathetic activity generally prepares the body for physical activity.
Sympathetic division produces more specialized effect than parasympathetic division.