Page - 70 - in Advances in Neuroimmunology

BrainSci. 2016,6, 16 Figure2.PotentiatedMicroglialActivation intheEntorhinalCortexbyRepeatedEthanolExposure. OX-42 (CD11b) is upregulated in the entorhinal cortex of ethanol-exposed rats as shown in representativephotomicrographsofthe(A–C)entorhinalcortexfor(B)Con/EtOHand(C)EtOH/EtOH groupscomparedto (A) controls.AnalysisofOX-42 immunoreactivity indicatedthat theEtOH/EtOH grouphadsignificantlymorepositivepixels thantheCon/EtOHgroupinthe(D) entorhinalcortex. Data expressed as a percentage of ad libitum control (not shown). Images were taken at 200ˆ magnificationwith insetsat600ˆmagnification. Scalebar=100μm;inset30μm. *p<0.05compared toad libitumandCon/Congroups;#p<0.05comparedtoCon/EtOH. Table4.NoCorrelationbetweenOX-42andModelParametersorMicrogliaNumber. - Hippocampus EntorhinalCortex Parameter Con/EtOH EtOH/EtOH Con/EtOH EtOH/EtOH IntoxicationBehavior S=0.433 S=0.523 S=0.628 S=0.371 Dose/Day p=´0.321 p=´0.053 p=´0.488 p=´0.456 TotalDose p=´0.303 p=´0.0267 p=´0.331 p=´0.575 BEC p=0.424 p=´0.572 p=´0.082 p=0.032 PercentWeightLoss p=´0.222 p=0.249 p=0.029 p=0.319 Iba-1+Cells p=0.161 p=0.539 p=´0.136 p=0.357 3.3. LackofED-1orOX-6PositiveCells TheED-1antibodywasusedtoidentifyphagocyticmicroglia,whereasOX-6wasusedtovisualize the upregulation ofMHC-II [26,29]. No ED-1 (Figure 3) positive cellswere observedwithin the parenchymaof thehippocampusorentorhinalcortexofanyanimal inanygroup.NoOX-6 (Figure4) positivecellswereobservedwithin theparenchymaof thehippocampusorentorhinalcortexofany group, except foroneEtOH/EtOHtreatedanimal. ThisanimalhadseveralOX-6cells in themore posterior regionsof thehippocampusandentorhinalcortex (Figure4D,H)butwasnotanoutlier for anyintoxicationparameter includingBEC, intoxicationbehavior,orethanoldoseperday. Interestingly, themorphologyof thesecells still appeared tobecharacteristicof the lowgrade,partial activation state ofmicroglia as they are ramifiedandnot amoeboid [26]. ED-1 andOX-6positive cellswere visible in bloodvessels, thehippocampalfissure, andalong themeninges in all treatment groups (Figures3and4)similar to thatobservedpreviously followingbingeethanolexposure [22,60]. Thus, repeatedexposure to four-daybingeethanol treatment failed tosignificantly inducemicroglia toa phagocyticphenotypeorstate thatexpressedMHC-II in thebrainparenchyma. 70