Type 1 Vs Type 2 5AR and DHT Synthesis

[persistentone]

As I understand it, DHT is the result of an enzyme 5AR that has two types. Type 1 synthesizes DHT in the hair sebaceous gland, which is above the follicle and close to the scalp surface. Type 2 synthesizes DHT in the hair follicle. Finasteride only attacks type 2. Neither Minoxidil nor Finasteride attacks Type 1 5AR. So in theory we all have a lot of DHT collecting in the sebaceous gland, and nothing is treating that.

Has anyone studied how much of hair loss is attributable to DHT in the hair follicle versus DHT in the sebaceous gland? One would assume Type 2 is the most likely cause of hair loss (because it attacks the follicle directly), but you can easily imagine that the DHT in the sebaceous gland would leak into the follicle and therefore expose the follicle to additional DHT. Is that a question anyone has addressed or attempted to quantify?

 

[persistentone]

As I understand it, DHT is the result of an enzyme 5AR that has two types. Type 1 synthesizes DHT in the hair sebaceous gland, which is above the follicle and close to the scalp surface. Type 2 synthesizes DHT in the hair follicle. Finasteride only attacks type 2. Neither Minoxidil nor Finasteride attacks Type 1 5AR. So in theory we all have a lot of DHT collecting in the sebaceous gland, and nothing is treating that.

Has anyone studied how much of hair loss is attributable to DHT in the hair follicle versus DHT in the sebaceous gland? One would assume Type 2 is the most likely cause of hair loss (because it attacks the follicle directly), but you can easily imagine that the DHT in the sebaceous gland would leak into the follicle and therefore expose the follicle to additional DHT. Is that a question anyone has addressed or attempted to quantify?

And a related question would be how much does aggressive scalp massage, multiple shampooings each shower, and agents for accelerating skin peeling (e.g., Retin A) affect the Type 1 DHT in the sebacious gland?

 

[happychineseboy]

I could be completely wrong but I though finasteride stopped up type1 and type 2 but not type 3 while duta gets all there

 

[persistentone]

First sentence of this study:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1472914/

is "Finasteride selectively inhibits the Type 2 isoenzyme of 5α-reductase (5AR) (the enzyme responsible for converting testosterone to dihydrotestosterone [DHT]) whereas dutasteride inhibits both Type 1 and Type 2 5AR. "