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生长激素(growth hormone,GH)在行使其功能时需要经历一系列的过程,包括从垂体分泌和进入血液循环到达靶器官或细胞(受体前过程)以及和生长激素受体(GH receptor,GHR)结合并引发细胞内信号转导(受体后过程)。胰岛素可以直接或间接地影响这些过程。GH从垂体的生长激素分泌细胞中分泌需要依赖于下丘脑释放的生长激素释放激素(GH-releasing hor-mone,GHRH)和生长激素抑制素(somatostatin,SS),在生理或病理条件下,胰岛素可以对这两种激素以及GH分泌细胞施加不同影响,从而干预GH的分泌及循环水平。血糖、血脂以及饮食习惯都可以改变胰岛素对GH的影响。胰岛素还能通过影响GHR的敏感性,以及影响胰岛素样生长因子-1(insulin-like growth factor 1,IGF-1),进而影响GH。受体后过程也是GH行使功能的重要一环,细胞内信号转导依赖于信号通路完成。GH信号转导通路和胰岛素的信号通路有部分交叉,这使得两者的信号可以相互作用,胰岛素通过这种作用对GH的信号转导产生影响。还有很多因素可以改变胰岛素对GH的影响,包括细胞因子信号抑制物、GHR敏感性以及JAK2蛋白和胰岛素受体底物间的相互作用,且随着胰岛素浓度升高和作用时间延长,胰岛素对GH的影响趋向于增强。但胰岛素的浓度和时间对GH分泌和细胞内信号转导的具体影响还未完全阐明。胰岛素和SS的关系也有待进一步研究。
Growth hormone (GH) undergoes a series of processes that perform its function, including secretion from the pituitary and into the bloodstream to the target organ or cell (pre-receptor process) and to the growth hormone receptor (GHRR, GHR ) And trigger intracellular signal transduction (post-receptor processes). Insulin can affect these processes directly or indirectly. GH Secretion of GH-releasing hormones (GHRH) and somatostatin (SS), which are dependent on hypothalamic release, from the pituitary ghrelin secretion cells, under physiological or pathological conditions, insulin Both hormones and GH-secreting cells can exert different effects that interfere with the secretion and circulating levels of GH. Blood glucose, blood lipids and diet can change the impact of insulin on GH. Insulin also affects GH by affecting the sensitivity of GHR and affecting insulin-like growth factor-1 (IGF-1). Receptor process is also an important part of the GH function, intracellular signal transduction depends on the signal pathway to complete. GH signal transduction pathway and insulin signal pathways are partially cross, which makes the two signals can interact with insulin through this effect on the GH signal transduction impact. There are many other factors that can alter the effect of insulin on GH, including cytokine signaling inhibitors, GHR sensitivity, and the interaction between the JAK2 protein and the insulin receptor substrate. With increasing insulin concentration and duration of action, the insulin pair The impact of GH tends to increase. However, the specific effects of insulin concentration and time on GH secretion and intracellular signal transduction have not yet been fully elucidated. The relationship between insulin and SS needs to be further studied.