Expression of Kir4.1 immunoreactivity (IR) in glial tumor from patients with and without epilepsy. (A) Control white matter showing Kir4.1 IR in processes of perivascular astrocytes. (B) Astrocytoma grade II (A II); (C-F) Representative photomicrographs of Kir4.1 IR in astrocytoma grade III (A III; C and D) and glioblastoma multiforme (GBM; E and F) with (C and E) and without epilepsy (D and F); inserts: high magnifications, showing cytoplasmic staining, with weak IR in epilepsy-associated tumors. Sections were counterstained with hematoxylin. Scale bars: A: 40 μm; B-F: 160 μm. (F) Representative immunoblot of total homogenates from control cortex and GBM (with and without epilepsy) that revealed a band at a molecular weight of approximately 40 kDa.