Dynamic and chronobiological changes of endocrine indices in myotonic dystrophy

In a mixed group of males and females with myotonic dystrophy, baseline levels of gonadotropins are coherent with the condition of primary hypogonadism. The responses of LH and FSH to LH-RH are preserved, as well as those of STH to hypoglycemia and of PRL to dopaminergic drugs. PRL baseline levels in males are higher in respect to normal controls. Circadian rhythm is, however, preserved. Hourly periodicity of LH in males is impaired, with an increased frequency of pulses of decreased amplitudes.