['To study the cellular distribution of endothelin receptors A and B (ETrA and ETrB) in the post-traumatic sensorimotor cortex and hippocampus.', "We inflicted closed head trauma to male Sprague-Dawley rats and visualized ETrA and ETrB immunoreactivity with 3,3'-diaminobenzidine.", 'ETrA immunolabeling was the most prominent in pyramidal neurons 24 and 48 hours post-trauma, while it reached its peak in the microvasculature at hour 4. ETrB immunolabeling was observed in endothelial cells, perivascular neurons, smooth muscle cells (SM) and pericytes, the expression being the most pronounced 24 hours post-trauma.'] Are spatial alterations in endothelin receptor expression temporally associated with the altered microcirculation after brain trauma?