Herbicideacetochlorinhibitsadrenergicreceptor-mediatedcalciumoscillationsinrathepatocytesLIUFangyuan1）ZHANGBinbin1，2）CUIZongjie1）†（1）InstituteofCellBiology，BeijingNormalUniversity，100875，Beijing，China；2）CenterforBiotechnologyExperimentalTeaching，SchoolofPharmacy，BinzhouMedicalUniversity，264003，Yantai，Shandong，China）AbstractHerbicideacetochlorafterapplicationentersbothsurfaceandundergroundwaters，sothatacetochlorconcentrationsinriversandstreamscouldbesufficientlyhigh（nmol·L−1）toexertlong-termeffectsinaquaticanimals.Occupationalexposuremayposegreaterrisksduetoskinandinhalationexposures，resultinginmuchhighertransientbloodacetochlorconcentrations（μmol·L−1）.Previousworkshaveidentifiedliverasthemostsusceptibletoxicologicaltargetforacetochlor，andcytosoliccalciumisknowntoplayavitalroleinmultiplehepatocytefunctions.Thereforethepresentworkaimstoexamineacetochloreffectoncalciumoscillationsinducedbyadrenergicreceptoractivationinfreshlyisolatedrathepatocytes.Itwasfoundthatacetochloratlowerconcentrations（1，10μmol·L−1）addedsimultaneouslywithphenylepinephrine（PE）hadnoeffectonPE-inducedcalciumoscillations，butinhibitedreversiblycalciumoscillationsathigherdoses（50，100，200μmol·L−1）ofacetochlorinselectedhepatocytes.Briefprioracetochlorexposure（1，10，100μmol·L−1），however，hadnoapparenteffectoneitherbasalcalciumorsubsequentPE-inducedcalciumoscillations.Immunocytochemistryidentifiednon-uniformα1adrenergicreceptorexpressionamongisolatedhepatocytes.Immunohistochemistryofliverslicesrevealedadistinctpatternofα1adrenergicreceptordensityinliverlobules:agraduallow-to-highreceptordensitygradientfrompericentraltoperiportalregions.Thisreceptordensitygradientislikelyrelatedtoacetochlorinhibitioninselectedhepatocytes.Takentogetheritisconcludedthatacetochloratbloodconcentrationsattainableduringacuteskinexposureoracetochlorpoisoningmayexerttransientinhibitoryeffectsonα1receptorsignalingintheliver.Keywordsacetochlor；adrenergicreceptor；calciumo...
