| BACKGROUND AND PURPOSES:Many kinds of sensorineuralhearing loss are related to immunity,but this is always ignored in clinical work.There is damnification of immunity in some diseases,such as :some of sudden hearing loss, Meniere disease,otosclerosis,chronic otitis media,the trauma of temporal bone and some systemic immunologic diseases accompied by hearing loss. Presently,there are many names of immunologic diseases in inner ears,and "autoimmune inner ear disease(AIED)" is the tentative name of all those immunologic diseases in inner ears.It is impossible to subject the inner ear to biopsy if the function of inner ears isn't affected.So it is limited to study these diseases and to realize the mechanism of these diseases.Setting up an animal model of these diseases is one effective way to explore the mechanism of these diseases.The main antigens which were used in many studies were type II collagen(C II ),the endolabyrin(homogeneous animals and heterogenous animals) and the sera of heterogenous animals.The methods of setting up animal models mainly concluded : systemic immunity,local challenge of inner ears and systemic immunity accompanied by local challenge.But local challenge of inner earsis not logical. Although various antigens evoked strong immune reaction,this model acted only as some of the mechanisms of AIED in clinical diseases(the antigen exposed to immune system under the conditions of operation and trauma). Type II Collagen is simpler than other antigens and the antibody to type II Collagen has been found in patients' sera.Some researchers have set up the AIED models in different animals,but the difference of the results was great and the viewpoints were different.There was few research to observe the intercellular adhesion molecule l(ICAM-l) in the early stage of immunity of the inner ears .The purposes of this experiment are those :one is to find whether CII plays an important role in AIED,the other is to observe the expression of ICAM-1 at the early stage of animal model.This experiment will set up AIED model in guinea pigs with chicken type II collagen(CC II ) and examin the function of the inner ears,observe the morphologic changes and the expression of ICAM-1 of inner ears at the early stage of the animal model.MATERIALS AND METHODS: Sixty five guinea pigs positive inpreyer reflex,weighing from 150 to 200 grams,were randomly divided into 3 groups.Group I (10 guinea pigs,20 ears), the normal control group,were under no treatment,and at the same time as group 111,5 of the 10 guinea pigs were sacrificed respectively. Group II (15 guinea pigs,l died ,28 ears),the collagenic group,at the first time were injected subcutaneously with 0.1 ml complete Freundadjuvant(CFA),and at the following 5 times were injected subcutaneously with 0.1 ml incomplete Freundadjuvant(IFA) weekly. Seven guinea pigs were sacrificed respectively on 3rd and 14th day after the last injection. Group 111(40 guinea pigs,3 died),the experimental group, at the first time were injected subcutaneously with 0.1 ml the emulsion of CC II (400 u g) and CFA, and at the following 5 times were injected subcutaneously with 0.1 ml the emulsion of CClI(200u g) and IFA weekly. 19 and 18 guinea pigs were sacrificed respectively on 3rd and 14th day after the last injection. Auditory brainstem response audiometry(ABR) was recorded in each group before the sacrifiction.The inner ears of 2 animals in group I and II and 5 animals in group IIIwere used for scanning electron microscope,and the others were used to observe the expression of ICAM-1 .The data were disposed by software SPSS.RESULTS1. ABR The latencies of all waves and the interpeak latencies of I -III had no significance in group I compared with those in group II (P>0.05),delayed in group III compared with those in group I and group II (P<0.05),and delayed in the animals of 3rd day compared with those in the animals of 14th day(P<0.05).Threshold had no significance in group I compared with this in group II (P>0.05),increased in group III compared with th... |
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