Fig. 1

Intraarterial endothelin-1 does not trigger spreading depolarization in mice. a Timelines of intracarotid infusion experiments (left) and experimental setup (right). After the surgical preparation, saline was infused from carotid catheter at 1.5 μl/min. Then vehicle or endothelin-1 (ET-1) was infused through the carotid catheter. Numbers on each horizontal bars indicate infusion rate. For carotid infusions, catheter was inserted retrogradely into the external carotid artery and spreading depolarizations (SD) were detected using glass microelectrodes placed on both hemispheres and a laser Doppler on the ipsilateral hemisphere. b SD occurrence rates (upper panel) and total infusion volumes (lower panel). Four out of 19 mice (21%) developed SD during saline infusion. During vehicle infusion, one out of 7 mice had SD (14%), while endothelin-1 (ET-1) infusion triggered SD in 6 out of 12 mice (50%, p = 0.14, Chi-square test). In the presence of heparin, neither saline nor ET-1 infusion triggered an SD in any of the 8 mice studied (p = 0.011 versus no heparin, Chi-square test). Mean ± standard errors are shown