The aim of the current study was to demonstrate the distribution of VEGFR-2 on glioma microvascular endothelial cells on a nanoscale and investigate changes in VEGFR‑2 activity following treatment with the VEGFR‑2 inhibitor and agonist sorafenib and bradykinin, respectively. Three groups were evaluated in this study: Control glioma microvascular endothelial cells, sorafenib‑treated glioma microvascular endothelial cells and bradykinin‑treated glioma microvascular endothelial cells. Changes in the activity of VEGFR‑2 on the glioma microvascular endothelial cell membranes following treatment with sorafenib and bradykinin were characterized by atomic force microscopy (AFM). Colloidal gold‑labeled immune complexes and AFM were used to visualize the distribution of VEGFR‑2 on the cell membranes. In the control group, VEGFR‑2, which was observed as numerous globular structures, was evenly distributed on the cell surface membranes. The majority of the receptors were active. In the sorafenib group, only a few globular structures were observed on the cell membranes, with a density significantly lower than that in the control group (P<0.01). Furthermore, compared with the control group, fewer of the receptors were active. In the bradykinin group, numerous globular structures were densely distributed on the cell membranes, with a density significantly higher than that in the control group (P<0.01). The distribution and activity of VEGFR‑2 on glioma microvascular endothelial cell membranes treated with sorafenib and bradykinin suggested that the activity of VEGFR‑2 could be regulated by its inhibitor or agonist.

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