Study of thyrotropic reserve in diabetics of adult type.

The thyrotropic reserves in 13 diabetics without clinical evidence of vasculopathy have been studied and compared with 11 normal subjects. TSH basal levels were found to be lowered when compared with normal ones. When their pituitary gland had been stimulated with synthetic TRH, it was observed that they had a greater response. It is assumed that the diabetics may have some kind of hypothalamic disturbance that might be responsible for the low basal levels of TSH. This, in some way, would create greater sensibility of the thyrotrops. Some borderline hypothyroidism may exist in adult-onset diabetes.