Increased TRH Content of the Basal Ganglia in Huntington's Disease

To the Editor: Our recent observation that the amount of thyrotropin-releasing hormone (TRH) contained in the rat striatum can be markedly affected by drugs and lesions (Spindel ER, Pettibone DJ, Wurtman RJ. Unpublished data) prompted us to measure TRH post mortem in basal ganglia of brains of patients dying of Huntington's disease. TRH was assayed with the method previously described for rat striatum.¹ (The stability of brain TRH post mortem has previously been established by Okon and Koch.²) We observed that TRH levels were elevated nearly threefold over those seen in caudates and putamens from control subjects (Table 1).