...deiodinases (DIO1 and DIO2). T4 and T3 are inactivated by 5deiodination catalyzed by type 3 deiodinase (DIO3) with the formation of 3,3′5′triiodothyronine
(reverse T3, or rT3) and 3,3′diiodothyronine (T2), respectively (Bianco et al. 2002, Bianco 2011). The human brain has no
DIO1 activity (Campo ~~~