Adrenergic Receptors

[MedPR]

This is a passage based question. The relevant part of the passage is below.
The neuronal cell bodies of the postganglionic neurons are mainly contained in the sympathetic paravertebral chain ganglion located on either side of the spinal cord. One exception to this rule is the nerves innervating the adrenal medulla, which synapse directly onto the chromaffin cells. Chromaffin cells are themselves modified postganglionic neurons.

Which of the following cell types most likely contain adrenergic receptors?

A. chromaffin cells
B. sympathetic postganglionic neurons
C. parasmpathetic postganglionic neurons
D. cardiac muscle cells

---

Members don't see this ad.

 

[Ssina]

my guess would be D!?
since it's talking about which cell has the receptor!:
A. should be Nicotinic, since it's being innervated by ACh of pre-gang symp
B. post-gang of sym have Nicotinic also since innervated by ACh
C. same as B

 

[MedPR]

my guess would be D!?
since it's talking about which cell has the receptor!:
A. should be Nicotinic, since it's being innervated by ACh of pre-gang symp
B. post-gang of sym have Nicotinic also since innervated by ACh
C. same as B

D is correct. I thought adrenergic receptors were for epinephrine/norepinephrine, which is postganglionic sympathetic? Am I missing something?

 

[Pisiform]

D is correct. I thought adrenergic receptors were for epinephrine/norepinephrine, which is postganglionic sympathetic? Am I missing something?

Yes, you are correct. Adrenergic receptors are the receptors of epinephrine. This means that Adrenergic receptors are the target (destination) of epinephrine. The hormone epinephrine/noreponephrine which is secreted by post-ganglionic neurons will go to their destination which is the target cell (in this case cardiac muscles) which has receptors (adrenergic receptors) for them. Important thing is that epinephrine is secreted by post-ganglionic neurons but they act on target cells (which has adrenergic receptors)

 

[MedPR]

Yes, you are correct. Adrenergic receptors are the receptors of epinephrine. This means that Adrenergic receptors are the target (destination) of epinephrine. The hormone epinephrine/noreponephrine which is secreted by post-ganglionic neurons will go to their destination which is the target cell (in this case cardiac muscles) which has receptors (adrenergic receptors) for them. Important thing is that epinephrine is secreted by post-ganglionic neurons but they act on target cells (which has adrenergic receptors)

Oh I see. So all autonomic postganglionic neurons have cholinergic receptors, since the preganglionic neuron secretes Ach. Then the postganglionic neuron secretes epi/norepi, which travels to the adrenergic receptor on the effector.

Thanks!

 

[ilovemedi]

Sorry for bumping this, but is it really necessary to memorize the Nicotinic vs. adrenergic receptors and which system (somatic/auto/para/sympathetic) uses which?! Isn't that way too detailed to memorize?

 

[dyspareunia]

Sorry for bumping this, but is it really necessary to memorize the Nicotinic vs. adrenergic receptors and which system (somatic/auto/para/sympathetic) uses which?! Isn't that way too detailed to memorize?

To answer this question all you need to know is all pre-ganglionic autonomics use ACh as the neurotransmitter. Based on that you can figure out that "B" and "C" have cholinergic receptors. The passage tells you that "A" also has cholinergic receptors (since preganglionic synapse directly onto chromaffin cells). So even if you have no background knowledge, you come to the correct answer.

 

[ilovemedi]

To answer this question all you need to know is all pre-ganglionic autonomics use ACh as the neurotransmitter. Based on that you can figure out that "B" and "C" have cholinergic receptors. The passage tells you that "A" also has cholinergic receptors (since preganglionic synapse directly onto chromaffin cells). So even if you have no background knowledge, you come to the correct answer.

So we still need to know that "pre-ganglionic" cells autonomics use ACh? I guess I should memorize pre/post ganglionic cells?

 

[dyspareunia]

So we still need to know that "pre-ganglionic" cells autonomics use ACh? I guess I should memorize pre/post ganglionic cells?

Preganglionic neurons.. Yes you should know that.