for the ion and is often expressed as the percentage of the total (exchangeable)
amount of that ion in the body that moves in (K j) or out (K o ) of the fish each hour.
This provides a relatively simple and accurate method for comparing the permeability of different fish in various circumstances. Sticklebacks in sea-water were
found to exchange 20% of their total exchangeable sodium each hour, while in fresh
water only about 1% was moved. Potassium was exchanged far less rapidly; in
sea-water only 0.4 m-equiv/kg h was transferred (compared to 11 m-equiv/kg h
for sodium), but this increased about 3-fold in fresh water.
Table 7.9 Total sodium f/uxes * in fish bathed in various media
~
""
~o
:to
«:::..,.,
tl 'K (0/0 of total
:<: . ~
tl
:t
exchangeable
weight
t::.. ..
~ ~ Na lh)
grams
""Osteichthyes
Carassius auratus'» 2
FW
27
(I
90-220
(Goldfish)
190 mM Na CI
553
8
Opsanus tau 3
10°/0 SW
52
(I
200-700
(Toadfish)
SW
805
16
Blennius pholis 4
10010 SW
50
8
2.5-7
(Blenny)
SW
2700
45
Platichthys f/esus s
FW
43
(I
60-390
(Flounder)
SW
2600
45
Anguilla anguilla 6
FW
4
(0.1
60-120
(Eel)
SW
1321
33
Fundulus beteroclitusl, s
FW
60
(0.1
9-20
(Killifish)
SW
2020
35
Gasterosteus aculeatus 9
FW
60
1
1-2
(Stickleback)
SW
1000
20
Tilapia mossambica'"
FW
200
3
0.5-3
SW
6000
66
Serranus scriba lt
SW
3100 Aprox.60
30-80
(Sea-water perch)
Chondrichthyes
Scyliorhinus caniculus l 2
SW
59
0.5
40-380
(Spotted dogfish)
Squalus acanthias l 3
SW
90
0.9
4000
(Spiny dogfish)
Hemiscyllium plagiosum'»
SW
75
0.74
155-1100
(Lip shark)
': . given from measurements of outflux.
References : IBoURGUET, LAHLOU, and MAETZ (1964); 2LAHLOU et al. (1969 a); 3LAHLOU and
SAWYER (1969); 4HouSE (1963); sM OTAIS and MAETZ (1965); MOTAIS et al. (1966); 6MAETZ,
MAYER and CHARTIER-BARADUC (1967 a); 7MAETZ, SAWYER, PICKFORD, and MAYER (1967 b) ;
sPOTTS and EVANS (1967); 9MuLLINS (1950); 10POTTS et at. (1967); tlMOTAIS and MAETZ
(1964); l2MAETZ and LAHLOU (1966); l3BuRGER and TOSTESON (1966); 14CHAN, PHILLIPS, and
CHESTER JONES (1967 b).
219
amount of that ion in the body that moves in (K j) or out (K o ) of the fish each hour.
This provides a relatively simple and accurate method for comparing the permeability of different fish in various circumstances. Sticklebacks in sea-water were
found to exchange 20% of their total exchangeable sodium each hour, while in fresh
water only about 1% was moved. Potassium was exchanged far less rapidly; in
sea-water only 0.4 m-equiv/kg h was transferred (compared to 11 m-equiv/kg h
for sodium), but this increased about 3-fold in fresh water.
Table 7.9 Total sodium f/uxes * in fish bathed in various media
~
""
~o
:to
«:::..,.,
tl 'K (0/0 of total
:<: . ~
tl
:t
exchangeable
weight
t::.. ..
~ ~ Na lh)
grams
""Osteichthyes
Carassius auratus'» 2
FW
27
(I
90-220
(Goldfish)
190 mM Na CI
553
8
Opsanus tau 3
10°/0 SW
52
(I
200-700
(Toadfish)
SW
805
16
Blennius pholis 4
10010 SW
50
8
2.5-7
(Blenny)
SW
2700
45
Platichthys f/esus s
FW
43
(I
60-390
(Flounder)
SW
2600
45
Anguilla anguilla 6
FW
4
(0.1
60-120
(Eel)
SW
1321
33
Fundulus beteroclitusl, s
FW
60
(0.1
9-20
(Killifish)
SW
2020
35
Gasterosteus aculeatus 9
FW
60
1
1-2
(Stickleback)
SW
1000
20
Tilapia mossambica'"
FW
200
3
0.5-3
SW
6000
66
Serranus scriba lt
SW
3100 Aprox.60
30-80
(Sea-water perch)
Chondrichthyes
Scyliorhinus caniculus l 2
SW
59
0.5
40-380
(Spotted dogfish)
Squalus acanthias l 3
SW
90
0.9
4000
(Spiny dogfish)
Hemiscyllium plagiosum'»
SW
75
0.74
155-1100
(Lip shark)
': . given from measurements of outflux.
References : IBoURGUET, LAHLOU, and MAETZ (1964); 2LAHLOU et al. (1969 a); 3LAHLOU and
SAWYER (1969); 4HouSE (1963); sM OTAIS and MAETZ (1965); MOTAIS et al. (1966); 6MAETZ,
MAYER and CHARTIER-BARADUC (1967 a); 7MAETZ, SAWYER, PICKFORD, and MAYER (1967 b) ;
sPOTTS and EVANS (1967); 9MuLLINS (1950); 10POTTS et at. (1967); tlMOTAIS and MAETZ
(1964); l2MAETZ and LAHLOU (1966); l3BuRGER and TOSTESON (1966); 14CHAN, PHILLIPS, and
CHESTER JONES (1967 b).
219