{Reference Type}: Journal Article
{Title}: Growth hormone increase by luteinizing hormone-releasing hormone reflects gonadotroph-related characteristics in acromegaly.
{Author}: Mitsui Y;Mukai K;Otsuki M;Oshino S;Saitoh Y;Kohara M;Morii E;Fukuhara A;Shimomura I;
{Journal}: Pituitary
{Volume}: 0
{Issue}: 0
{Year}: 2024 Jun 19
{Factor}: 3.599
{DOI}: 10.1007/s11102-024-01410-2
{Abstract}: <B>OBJECTIVE: </B>We previously showed the clinical characteristics of acromegaly with a paradoxical growth hormone (GH) response to oral glucose or thyrotropin-releasing hormone. However, the clinical characteristics of acromegaly with an increased GH response to luteinizing hormone-releasing hormone (LHRH responders) remain unclear. The aim of the present study was to evaluate the clinical characteristics, especially gonadotroph-related characteristics of LHRH responders in acromegaly.<BR><B>METHODS: </B>The clinical characteristics of 33 LHRH responders and 81 LHRH nonresponders were compared.<BR><B>RESULTS: </B>No differences in age, sex or basal serum levels of GH, insulin-like growth factor-1 (IGF-1), and gonadotropin were observed between the two groups. Steroidogenic factor 1 (SF-1), gonadotropin-releasing hormone receptor (GnRHR), and LH expression was more frequently observed in LHRH responders (P < 0.05). In addition, a greater increased rate of GH after LHRH loading, and the proportion of GnRHR and gonadotropin expression was observed in pituitary tumor with SF-1 expression than that without the expression (P < 0.01). LHRH responders showed a greater GH decrease in the octreotide test and a greater IGF-1 decrease after first-generation somatostatin ligand than LHRH nonresponders (P < 0.05). Furthermore, the proportion of hypointense pituitary tumors on T2-weighted magnetic resonance imaging and tumors with densely granulated type was higher in LHRH responders than in LHRH nonresponders, respectively (P < 0.05). No difference between the two groups was observed in either somatostatin receptor 2 or 5 expression.<BR><B>CONCLUSIONS: </B>The increased GH response to LHRH is associated with the gonadotroph-related characteristics. This response may reflect the biological characteristics of somatotroph tumors.