Enhancement of the GH responsiveness to GH releasing stimuli by lysine vasopressin in type 1 diabetic subjects

Abstract

These data show that in diabetic, but not in normal subjects LVP enhances the GH responsiveness to secretagogues, such as GH-RH, clonidine and arginine, which act through three different mechanisms. These findings suggest that in diabetes mellitus, vasopressin functions as a primer for various GH responses.

Effects of ghrelin, growth hormone–releasing peptide–6, and growth hormone–releasing hormone on growth hormone, adrenocorticotropic hormone, and cortisol release in type 1 diabetes mellitus

“…However, in our study, cortisol responsiveness to ghrelin and GHRP-6 was similar in T1DM and controls, which suggests that adrenal responsiveness to these peptides is unchanged in patients with T1DM. This is in agreement with previous reports showing normal cortisol responsiveness to metyrapone, lysine vasopressin, and ACTH in diabetic patients [17,19,22].…”

“…There are controversial findings in the literature about stimulated GH values in patients with T1DM. Both normal responsiveness and enhanced responsiveness to several stimuli, such as GHRH and hexarelin, have been reported [17][18][19]22,23,26,28]. We have previously shown that GH responses to GHRH and GHRP-6 are similar in T1DM and in healthy subjects [20].…”

“…Nine healthy subjects (6 men and 3 women) were also studied as a control group. Their mean age was 28.4 ± 1.5 years (range, [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35], and their mean BMI was 23.3 ± 0.8 kg/m 2 (range, 18.8-25.9). Mean HbA 1c was of 5.0% ± 0.1%.…”

“…In patients with type 1 diabetes mellitus (T1DM), basal GH levels are either normal [17][18][19][20][21][22] or elevated [23][24][25], depending on glycemic control; and insulin-like growth factor-I (IGF-I) levels are normal [20] or reduced [19,21,[24][25][26]. It has been suggested that the enhanced GH secretion might be due to a decrease in IGF-I feedback on the hypothalamic-pituitary unit [27].…”

Effect of acute reduction of free fatty acids by acipimox on growth hormone‐releasing hormone‐induced GH secretion in type 1 diabetic patients

“…Diabetes is associated with a generalized impairment in lipid metabolism and with increased plasma free fatty acid (FFA) levels (Basu et al ., 2001; Boden et al ., 2001), although others have found normal baseline plasma FFA in diabetic patients (Coiro et al ., 1999). A classic feedback relationship has been postulated between GH and the FFA.…”