Locations Of Alanine Aminotransferase In Amphioxus And The Changes Of Acute Inflammation Factors After Treatment With LPS And Vibrio Alginolyticus

A prominent systemic physiological reaction of the organism was caused byinfection,tissue injury and trauma,and in turn nervous-endocrine system wasreactivated by reactants and released the catecholamines (CAs).Thus acute phaseresponse was caused in the organism involved in acute phase proteins (APPs).Firstly,the presence and location of AAT in amphioxus was studied by Westernblotting and immunohistochemical methods.The results first revealed that AATpresent in amphioxus,a cephalochordate.Also it was demonstrated that AATdistributed in cellular plasma in hepatic diverticulum,the pouch that protrudesforward as an outpocketing of the digestive tube and extends along the right side ofthe posterior part of the pharynx,which has long been considered to be the precursorof vertebrate liver.In vertebrate,AAT is primary synthesized in liver.In view of thefact that AAT synthesized in hepatic diverticulum of amphioxus,the hepaticdiverticulum of amphioxus is physiological equal to the vertebrate liver.Thissupported the Müller's argument that vertebrate liver is evolved by the hepaticdiverticulum of amphioxus.Secondly,acute phase response and some APPs were studied in amphioxus.Itwas first revealed that presence of seven kinds of APPs in amphioxus humoral fluid,including Alanine aminotransferase (AAT),Aspartate transaminase (AST),Lactatedehydrogenase (LDH),Alkaline phosphatase (ALP),r-Glutamyltransferase(GGT) andα-Hydroxybutyrate Dehydrogenase (HBDH).Also it was demonstratedthat these proteins content changed respectively after the acute challenge withlipopolysaccharide,while the total protein remains basically unchanged.Among theseproteins,AAT,AST,GGT,LDH,HBDH and ALP increased dramatically after LPStreatment,while the other protein,RBP,decreased significantly.These resultsindicated that the similar acute phase response presented in eutherians has alreadyexisted in amphioxus,a cephalochordate.Thirdly,we studied acute phase response in amphioxus by detection of the change of the above mentioned acute proteins after got amphioxus infected by vibrioalginolyticus,a common disease-baring germ in sea water.The results revealed thatthe changes of these proteins extended the same trends after the disease germ infectedas the changes after LPS challenged.But changes in concentration ranges of six APPswere relatively small and six curves were relatively gentle.These results also provedthe presence of the same acute phase response profile in amphioxus,as observed ineutherians.Thus it pushed the evolutionary existence of the eutherian-like acute phaseresponse back to the protochordate lineage.Fourthly,we determined CAs,including epinephrine(E),norepinephrin(NE) anddopamine(DA),with HPLC method optimized after LPS challenged amphioxus.Theresults demonstrated that E,DE and DA are present in amphioxus humoral fluid,andE was firstly found in amphioxus.Moreover,it was demonstrated that the threesubstances,E,DE and DA,increased dramatically and quickly after LPS treatment.Also,it was revealed that the changes of three substances were more quickly than thechanges of the above mentioned APPs during the same LPS treatment.Thesesuggested that the three substances existed as neurotransmitter.The presence and thechange of the CAs in amphioxus after treated with LPS indicated the evolutionaryexistence of CAs and acute phase response in the protochordate lineage.In short,from neurotransmitters of CAs to APPs of amphioxus,as well as themain organ involved in the synthesis of APPs,these all indicated that the similar acutephase response system presented in eutherians has already existed in amphioxus,acephalochordate.