378
D. HAROLD COPP
Table I
Calcium and Phosphate in Serum and in the Environments
Environment and
Total Ca
Ionic Ca
Total P
Representative Species
(mmole/liter)
(mmole/liter)
(mmole/liter)
Environment
Pacific Ocean
Brakish water
Lake Huron
Marine Invertebrate
Nephropsb
Cyclostomes
Hagfish, E. stoutii
Lamprey, P . marinus
Ratfish, H . wllieib
Marine shark, C. Zeucus
Freshwater shark,
Chimaerid
Elasmobranchs
C. leucas nicaraguensis
Teleost
Marine, P. clathratus
Freshwater, M . atlaneia
Man, H . sapienp
Mammal
10.0 f 0 . 1
2-5
0 . 9 f O . l
11.95
5 . 4 f O . l
2.60 f 0 . 1
4 . 8 f 0 . 3
4.50 f 0 . 9
3 . 0 f 0 . 2
3 . 2 f 0 . 8
2 . 5 f 0 . 2
2.32 f 0.08
10.0
-
0 . 9 f 0 . 1
3 . 0 f 0 . 4
1.74 f 0 . 2
3.10 f 0 . 4
1 . 7 f O . l
2 . 0 f 0 . 9
1 . 8 f 0 . 2
1.15
0.00
0.003
-
1 . 5 f 0 . 2
1 . 3 f O . 1
2 . 2 f 0 . 4
2 . 0 f 0 . 6
1 . 6 f 1 . 7
2 . 0 f 0 . 2
1 . 2 f 0 . 4
Urist (1963).
Urist (1966).
Copp (1963).
In contrast, all vertebrates have some capacity to regulate their serum
calcium at a level different from that in the surrounding environment
(see Table I). This is an important factor in their ability to adapt to
varying environmental conditions.
A. Calcium Regulation in Mammals
In mammals, the level of calcium in plasma and extracellular fluid is
regulated with great precision (Copp, 1964). In 273 adult men, the
average value for total plasma calcium was 9.10 f 0.24 mg% (mean A
standard deviation) and the diurnal fluctuation in individuals was less
than ~ 0 . 3
mg % (Carruthers et al., 1964). Approximately half of the total
calcium is diffusible and ionized. Precise control of ionic calcium is important for it affects many vital processes, including neuromuscular
excitability, muscle contraction, activity of many enzymes, and permeability of cell membranes to water and electrolytes. Rasmussen and
D. HAROLD COPP
Table I
Calcium and Phosphate in Serum and in the Environments
Environment and
Total Ca
Ionic Ca
Total P
Representative Species
(mmole/liter)
(mmole/liter)
(mmole/liter)
Environment
Pacific Ocean
Brakish water
Lake Huron
Marine Invertebrate
Nephropsb
Cyclostomes
Hagfish, E. stoutii
Lamprey, P . marinus
Ratfish, H . wllieib
Marine shark, C. Zeucus
Freshwater shark,
Chimaerid
Elasmobranchs
C. leucas nicaraguensis
Teleost
Marine, P. clathratus
Freshwater, M . atlaneia
Man, H . sapienp
Mammal
10.0 f 0 . 1
2-5
0 . 9 f O . l
11.95
5 . 4 f O . l
2.60 f 0 . 1
4 . 8 f 0 . 3
4.50 f 0 . 9
3 . 0 f 0 . 2
3 . 2 f 0 . 8
2 . 5 f 0 . 2
2.32 f 0.08
10.0
-
0 . 9 f 0 . 1
3 . 0 f 0 . 4
1.74 f 0 . 2
3.10 f 0 . 4
1 . 7 f O . l
2 . 0 f 0 . 9
1 . 8 f 0 . 2
1.15
0.00
0.003
-
1 . 5 f 0 . 2
1 . 3 f O . 1
2 . 2 f 0 . 4
2 . 0 f 0 . 6
1 . 6 f 1 . 7
2 . 0 f 0 . 2
1 . 2 f 0 . 4
Urist (1963).
Urist (1966).
Copp (1963).
In contrast, all vertebrates have some capacity to regulate their serum
calcium at a level different from that in the surrounding environment
(see Table I). This is an important factor in their ability to adapt to
varying environmental conditions.
A. Calcium Regulation in Mammals
In mammals, the level of calcium in plasma and extracellular fluid is
regulated with great precision (Copp, 1964). In 273 adult men, the
average value for total plasma calcium was 9.10 f 0.24 mg% (mean A
standard deviation) and the diurnal fluctuation in individuals was less
than ~ 0 . 3
mg % (Carruthers et al., 1964). Approximately half of the total
calcium is diffusible and ionized. Precise control of ionic calcium is important for it affects many vital processes, including neuromuscular
excitability, muscle contraction, activity of many enzymes, and permeability of cell membranes to water and electrolytes. Rasmussen and