The catecholamines

[wildcat]

Hey everyone,

 

I had a question about the a part of the endocrine system, particularly the hormones called the chatecholamines.

 

If the chatecholamines (epinephrine, norepinehprine and dopamine) are synthesized by modifying tyrosine, would a person

with a metabolic disorder like albinoism (a tyrosinase deficiency)have a reduced fight-or-flight response when put in a stressful situation?

 

I know that tyrosinase is an enzyme (otherwise, it wouldn't have the suffix -ase), but would that have any effect on the sympathetic nervous system?

 

Thanks

[Greippi]

Adrenaline (ephinephrine) can also be synthesised from phenylalanine, so I assume if there was a problem with converting tyrosine to adrenaline, phenylalanine would just be used instead.

 

HOWEVER:

 

In the adrenaline synthesis pathway, tyrosine is oxidised using tyrosine hydroxylase, not tyrosinase.

[psynapse]

A person with albinism will not have an affected fight or flight response. The reason is tyrosinase converts tyrosine to melanin a pigment compound.

 

Tyrosine Hydroxylase a different enzyme is responsible for converting tyrosine into L-Dopa and subsequently the catecholamines.