ACE levels in CSF were lower in patients with NMO/NMOs (34.3+/-5.61 ng/ml) than in MS patients (42.5+/-8.19 ng/ml, P(corr)=0.035) and controls (44.7+/-4.02 ng/ml, P(corr)<0.0003) while ACE2 levels were lower in NMO/NMOs (1.13+/-0.49 ng/ml) and MS (1.75+/-0.86 ng/ml) patients than in controls (2.76+/-0.23 ng/ml, P(corr)<0.001 for both).