Somatostatin is a polypeptide hormone that inhibits the secretion of various hormones (such as growth hormone, insulin, and glucagon) by binding to G protein-coupled receptors SSTR1-5[1, 2]. Somatostatin, produced in the hypothalamus of the central nervous system and various peripheral tissues such as the neocortex and hippocampus, regulates multiple bodily functions by impeding the release of other hormones, gastrointestinal activity, and rapid cell proliferation[3, 4]. Somatostatin is commonly used in the treatment and research of conditions such as bleeding caused by gastrointestinal issues, various neuroendocrine tumors, and diabetic complications[2].
In vitro, treatment of chicken cone photoreceptors with Somatostatin (500nM) for 2h significantly reduced the current density of L-type voltage-gated calcium channels (L-VGCCs) during the subjective night (circadian time (CT) 16-19), but no such effect was observed during the subjective day (CT 4-7)[5]. In HEK293 cells co-expressing Sst5-CFP (fluorescence donor) and D2-YFP (fluorescence acceptor) receptors, treatment with Somatostatin (1μM) for 30min significantly induced heterodimerization between Sst5 and dopamine D2 receptors, increasing the fluorescence resonance energy transfer (FRET) efficiency from 1.83% to 9.74%[6].
In vivo, subcutaneous injection of Somatostatin (20μg/100g body weight; twice a day) for 5 consecutive days to virgin female Wistar rats significantly reduced the cell volume and volume density of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) immunopositive cells, and markedly decreased serum levels of FSH and LH[7]. In swamp eels fed a high-fat diet, intraperitoneal implantation of Somatostatin (0.71mg/g body weight) via PLGA microspheres for 56 days significantly mitigated lipogenesis, reduced whole-body and muscle lipid accumulation, and increased serum high-density lipoprotein cholesterol (HDL-C) levels[8].
References:
[1] PATEL Y C. Somatostatin and its receptor family[J]. Frontiers in neuroendocrinology, 1999, 20(3): 157-198.
[2] GOMES-PORRAS M, CÁRDENAS-SALAS J, ÁLVAREZ-ESCOLÁ C. Somatostatin analogs in clinical practice: a review[J]. International journal of molecular sciences, 2020, 21(5): 1682.
[3] MARTEL G, DUTAR P, EPELBAUM J, et al. Somatostatinergic systems: an update on brain functions in normal and pathological aging[J]. Frontiers in endocrinology, 2012, 3: 154.
[4] LIGUZ-LECZNAR M, URBAN-CIECKO J, KOSSUT M. Somatostatin and somatostatin-containing neurons in shaping neuronal activity and plasticity[J]. Frontiers in neural circuits, 2016, 10: 48.
[5] JIAN K, BARHOUMI R, KO M L, et al. Inhibitory effect of somatostatin-14 on L-type voltage-gated calcium channels in cultured cone photoreceptors requires intracellular calcium[J]. Journal of neurophysiology, 2009, 102(3): 1801-1810.
[6] SZAFRAN K, ŁUKASIEWICZ S, FARON-GÓRECKA A, et al. Antidepressant drugs promote the heterodimerization of the dopamine D2 and somatostatin Sst5 receptors—fluorescence in vitro studies[J]. Pharmacological Reports, 2012, 64(5): 1253-1258.
[7] NESTOROVIĆ N, MANOJLOVIĆ-STOJANOSKI M, RISTIĆ N, et al. Somatostatin-14 influences pituitary–ovarian axis in peripubertal rats[J]. Histochemistry and Cell Biology, 2008, 130(4): 699-708.
[8] CHAO B, LIAO S, CHEN Z, et al. Somatostatin-14 mitigates high-fat diet-induced lipid metabolic dysregulation in swamp eel (Monopterus albus)[J]. Aquaculture, 2025, 743114.
Somatostatin是一种通过与G蛋白偶联受体SSTR1-5结合来抑制多种激素（如生长激素、胰岛素和胰高血糖素）分泌的多肽类激素[1,2]。Somatostatin由中枢神经系统下丘脑及外周新皮层、海马等多种组织部位产生，通过阻碍其他激素的释放、胃肠道的活动和细胞的快速繁殖来调节多种身体功能[3,4]。Somatostatin通常用于胃肠道问题引起的出血、各种神经内分泌肿瘤和糖尿病并发症等疾病的治疗和研究[2]。
在体外，Somatostatin（500nM）处理鸡视锥细胞2h，在主观夜间（circadian time (CT) 16-19）显著降低了L型电压门控钙通道（L-VGCC）的电流密度，而在主观白天（CT 4-7）则无此效果[5]。Somatostatin（1μM）处理共表达sst5-CFP（fluorescence donor）和D2-YFP（fluorescence acceptor）受体的HEK293细胞30min，显著诱导了Sst5与多巴胺D2受体的异源二聚化，使荧光共振能量传递（FRET）效率从1.83%增加至9.74%[6]。
在体内，给予未曾交配过的雌性Wistar大鼠皮下注射Somatostatin（20μg/100g; twice a day）连续5天，显著降低了卵泡刺激素（FSH）和黄体生成素（LH）免疫阳性细胞的细胞体积和体积密度，并显著降低了血清中FSH和LH的水平[7]。Somatostatin（0.71mg/g body weight）通过PLGA微球腹腔植入高脂饮食黄鳝56天，显著缓解了脂肪生成，减少了全身和肌脂积累，并提高了血清高密度脂蛋白胆固醇（HDL-C）水平[8]。