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norepinephine and epinephine?


#1

What is the difference betweeen norepinephrine and epinephine?


#2

a search on google should give you an answer in about a minute or so.


#3

epinephrine attaches to beta 2 adrenoceptors better than norepinephrine.


#4

The structure is the exact same for each except epinephrine has a (H-N-CH3) molecule instead of the (NH2) molecule that norepinephrine has.

Norepinephrine is a precursor of epinephrine. 80% of adrenal medulla secretions are in the form of epinephrine. The major neurotransmitter released from the sympathetic nervouse system is norepinephrine.

A primary function of epinephrine is to stimulare glycogenesis in the liver and active muscle and lipolysis in adipose tissue and active muscle; norepinephrine is a powerful stimulator of lipolysis in adipose tissue.

They basically do the same thing. Hope this helps.


#5

If anyone cares, I came across another tidbit of knowledge while reading...

Epinephrine (adrenaline) stimulates heart rate.

Norepinephrine (noradrenaline) helps to maintain constant blood pressure.


#6

Paul, they actually both stimulate heartrate and maintain blood pressure by vasostriction.


#7

buy a physiology/endocrinology text book, you will love it!