Non-specific pituitary responses in insulin-dependent diabetes mellitus in children and adolescents.

Objectives: Several reports indicate a number of changes in the control of the release of PRL, LH, FSH, GH and beta-endorphin (B-EP) as a result of insulin-dependent diabetes mellitus (IDDM). In this study we evaluate the presence of non-specific pituitary responses to releasing hormones in IDDM children and adolescents. Methods: The non-specific effects of TRH on plasma GH, LH and B-EP levels and of GnRH on plasma GH, PRL, TSH and B-EP levels were measured in 16 IDDM children and in 16 healthy children matched by age and sex. All subjects were tested with injection of TRH (200 ?g i.v. bolus) and GnRH (50 ?g i.v. bolus). GH, TSH, PRL, LH and B-EP levels were evaluated with radioimmunological methods on blood samples collected before and after stimulation by releasing hormones. Results: GH and B-EP non-specific responses to TRH and GnRH were significantly more pronounced in IDDM patients than in controls. All patients showed at least one non-specific response to one of the two releasing hormones. No significant correlations were found between non-specific pituitary responses and the patient's age, the duration and onset of disease or the degree of metabolic control. Conclusions: These observations may indicate that: in IDDM hypothalamus-pituitary regulating mechanism is altered; the hormones whose levels are most often found to be abnormal in IDDM (other than insulin) are also hormones which respond non specifically to the neuropeptides TRH and GnRH