In vitro vasospasm assay and cytokine production in response to hemin. A. In vitro vasospasm of mouse aortic ring slice after 5-minute incubation with supernatant from primary microglial cell culture (PMG) exposed to 40 μM hemin for 24 hours. Each PMG culture was exposed to one mouse aortic ring and this was repeated four times. Error bars are standard deviations. B. TNF-α was measured in the PMG supernatant after 24 hours of hemin exposure. This was repeated four times to get standard deviations in this graph. No difference was seen between wild type (WT), TRIF−/−, and MyD88−/− PMG per the Bonferroni correction. One way ANOVA for both vasospasm and TNF-α secretion were significant (P <0.03, P <0.02, respectively).