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Relationships between secondary lamellar structure and dorsal aortic oxygen tension in Salmo gairdneri with gills damaged by zinc

1983; Finnish Zoological and Botanical Publishing Board; Volume: 20; Issue: 3 Linguagem: Inglês

1797-2450

Heikki Tuurala,

Zebrafish Biomedical Research Applications

T . • г 1 ■ I i 1983) we have proposed a mechanism for the Low concentrations ol dissolved oxygen / . г -n * г ч u i_ , . . . ■ . • , ' ° . regulation ol gill gas transler capacity by the increased the toxicity ol zinc to rainbow trout ■ ° , ,, P J? r, , , . . /т i j тш -j ■ J j u • .u intralamellar shunting ol blood through the basal (Lloyd 1960), indicating some disturbance in the , , c iU ь, . , 9 , ... 4 ' i ' г ,i г u rs • »u » channels ol the secondary lamellae in the gills, gas exchange ol the hsh. During the exposure to ,.„• ,. ж , ? , f , 0 . .. . r°, i* f ■ While the dillusion distance to most ol the blood lethal concentrations ol zinc, hsh died ol tissue j , , A n , . ,c, • , ш,л t, ' t , in-70 spaces ol the secondary lamellae is so short that P0n hypoxia (Skidmore 1970; Burton et al. 1972). L,, ,n . . и u »l 2 о ui +u 1 t ■ j jj i ol blood flowing through them should reach the Sublethal concentrations ol zinc decreased dorsal , .0 ., ° , ,, . r, -r/о и .i lmri same value as in the external water, the distance aortic P0„ sigmlicantly (Sellers et al. 1975). f . , , , , .' , ., . г,.. . у? & . ' v , f . , ' . trom water to the basal channels is so long that Disturbances in gas exchange of the hsh seem to , , , n . „ .. , , ^ ,a • j j u • /т i j blood flowing through them does not reach lull be due to the gill damage induced by zinc (Lloyd . . r? ° . incn ci j о m u 1 mo л/..uо saturation. Consequently the ditlerence between 1960; Skidmore & Tovell 1972; Matthlessen & OT jr. uи J j *l г .• i т> £.1 .то loc.поп. tl • Pm„ and Fa0„ should depend on the fractional Brafield 1973: Tuurala & Soivio 1982). The main 2j л .u2 u u i » uu *u r rr • i *11 . i j4 i . f., blood flow through channels to which the 02 ellect of zinc on the gills is the detachment ol the . f . .. . j&, j-rr • , , „ „ , j 1 ■ transfer is limited by dillusion. secondary lamellar epithelium from the underlying T .u. j • j , • , L , C, . . ., j «• In this study, zinc was used as a tool in order to pillar cell system. This increases the dillusion ■ j'-L . f , . ,, Sг L.jjiirс increase the dillusion distance from water to the distance Irom water to blood and also the fusion ol .. j riU . . .. • ... j i .1 i -1 blood spaces ol the secondary lamellae, especially the adjacent secondary lamellae, decreasing the . Г , . f ,u , ,, гч i *■ ... J /c., . , „7rT, ,. .тол т. i о ln the basal parts ol the lamellae. Dorsal aortic gill area (Skidmore & lovell 1972). iuurala & • c iV_ , jj^u с • • /Лот • u ^ • i , j oxygen tension ol the hsh was measured and the Soivio (1982) using morphometrical methods .,(0 i j • u » • ,u j . j . ' iii i • srills were analysed using morphometric methods analysed the structural and circulatory changes in ? j . u .u V ^ , , . / ... , , ,, ' s , ^ in order to see how the structural changes rainbow trout gill secondary lamellae exposed to , t j • , ■ . nT n° , ! .1 i 0 , • гч • oc u correlated with the increase in the Plo„ Pao„ sublethal concentrations ol zinc. During 9b h ,-«• • j rl 2 2 , л • u • с .l ditlerence in the same hsh. exposure to 1.25 mg/1 ol zinc the fusion ol the