Serum growth hormone (GH) and the responses to thyrotropin-releasing hormone (TRH) in diabetes mellitus: lack of evidence for TRH evoked GH secretion.

Since TRH has been reported to evoke GH secretion in diabetic patients, we have investigated the influences of the enhanced GH secretion normally seen in diabetic patients on this response by measuring serum GH concentrations in 27 non-ketotic, stable, insulin-dependent diabetic (IDD) patients (14 male, 13 female). GH concentrations were measured over periods of 1 hr prior to and 1 hr following IV administration of both 200 micrograms TRH and 2 ml N Saline given on separate days. GH concentrations were not statistically significantly different between males and females during the two 120 min test periods and in individual patients GH concentrations did not differ significantly at any time during the tests. Sixteen of the 27 patients (Group 1) demonstrated elevation of serum GH following TRH, which was not statistically different from 11 of 27 patients who showed increased GH concentrations following saline administration. Seven subjects (4 male, 3 female) had a higher peak GH concentration following TRH than during their own 2 pre-injection test periods or following saline. Eleven patients failed to show any GH rise following IV TRH (Group 2). During the TRH test periods integrated GH concentrations in Group 1 patients were not statistically significantly different from those of Group 2: Group 1, 7.1 (0.7-15.8) (median and range) mU.min.l(-1), Group 2, 2.7 (0.4-25.4) mU.min.l(-1).(ABSTRACT TRUNCATED AT 250 WORDS)