McCain H W, Bilotta J, Lamster I B
Life Sci. 1987 Jul 13;41(2):169-76. doi: 10.1016/0024-3205(87)90490-5.
Glycyl-L-glutamine (GLG), the carboxy terminal dipeptide of B-endorphin, inhibits brainstem neuronal activity. It also occurs along with B-endorphin in pituitary secretory vesicles suggesting a neurosecretory role for this dipeptide. We have evaluated potential immunoregulatory actions of this compound using the Phytohemaglutinin (PHA) blastogenesis and the concanavalin A (ConA) suppressor cell induction assays. GLG in low doses (10(-12) M) enhanced the response of human lymphocytes to PHA induced blastogenesis, however; with higher doses of the dipeptide (10(-7) M) immunosuppression was consistently observed. In the suppressor cell induction assay, when GLG was used together with ConA, we observed a dose-dependent inhibition of suppressor activity. These results clearly indicate that GLG produces a dose dependent bidirectional modulation of at least two indicies of immune function, and confirm the presence of a second pituitary peptide with the potential for potent immunomodulatory action.
甘氨酰-L-谷氨酰胺（GLG）是β-内啡肽的羧基末端二肽，可抑制脑干神经元活动。它还与β-内啡肽一同存在于垂体分泌小泡中，提示该二肽具有神经分泌作用。我们使用植物血凝素（PHA）刺激淋巴细胞增殖试验和刀豆蛋白A（ConA）诱导抑制细胞试验评估了该化合物的潜在免疫调节作用。然而，低剂量（10^(-12) M）的GLG增强了人淋巴细胞对PHA诱导的增殖反应；而高剂量（10^(-7) M）的该二肽则始终观察到免疫抑制作用。在抑制细胞诱导试验中，当GLG与ConA一起使用时，我们观察到抑制活性呈剂量依赖性抑制。这些结果清楚地表明，GLG对至少两种免疫功能指标产生剂量依赖性双向调节作用，并证实存在第二种具有强大免疫调节作用潜力的垂体肽。
