Immunohistochemical localization of prostaglandin F2 alpha in reperfused gerbil brain.

Immunohistochemical localization of prostaglandin (PG) F2 alpha synthesized during recirculation following experimental forebrain ischemia was studied in Mongolian gerbils. The bilateral carotid arteries were clamped for 5 minutes, and the brains were frozen in situ after 5 minutes of recirculation. Sham-operated gerbils not subjected to arterial occlusion served as controls. Cryostat sections containing dorsal hippocampus 10 microns in thickness were incubated in rabbit anti-PGF2 alpha serum and stained with avidin-biotin-peroxidase complex after fixation in carbodi-imide and Zamboni's solution. In specimens from control animals, blood vessels were faintly stained with anti-PGF2 alpha serum, while neurons and glial cells were less intensely stained or unstained. Specimens from reperfused gerbils demonstrated strongly positive staining for PGF2 alpha in blood vessels, neurons (especially hippocampal pyramidal neurons), and glial cells. Staining for PGF2 alpha in the reperfused animals was substantially diminished by pretreatment with indomethacin (10 mg/kg, i.p.). The results indicate that recirculation after forebrain ischemia results in an increase in PGF2 alpha in neurons, glial cells, and blood vessels.