Natriuretic Peptides in Antarctic Teleosts and Cardiac Receptors
211
of binding sites specific for both ANP and BNP, and interacting with
BNP at different affinities was observed in the mammalian heart [28,29].
Recently, pBNP was shown to specifically bind two types ofNPRs in the
rectal gland of the elasmobranch Squalus acanthias [30]. Although BNP
has not yet been identified in fish, its high sequence homology with
respect to the other piscine NPs [31] suggests that in the various cardiac
regions of both notothenioids, and particularly in the atrium of T
bernacchii, NP sites able to bind a BNP-like peptide exist.
Since homologous NPs from both T bernacchii and C. hamatus are not
available, caution must be exercised in analyzing the results using
heterologous ligands. However, the present data are of interest in
relation to the presence of a heterogeneous NP system in Antarctic
teleosts whose potential physiological significance needs to be further
investigated.
Acknowledgments
This research was supported by the Italian National Programme for Antarctic
Research (PNRA) (B. Tota).
References
1. Evans DH (1990) An emerging role for a cardiac peptide hormone in fish
osmoregulation. Ann. Rev. Physiol. 52: 43-60
2. Olson KR (1992) Blood and extracellular fluid volume regulation: role of
the renin-angiotensin system, kallykrein-kinin system, and atrial natriuretic
peptides. In: Fish physiology, Hoar WS, Randall DJ eds Academic Press
Inc Orlando, Florida, Vol XUB pp 135-254
3. Takei Y, Balment RJ (1993) Biochemistry and physiology of a family of
eel natriuretic peptides. Fish Physiol Biochem 11: 183-188
4. Acierno R, Axelsson A, Tota B, Agnisola C, Nilsson S (1991) Hypotensive
effect of atrial natriuretic factor (ANF) in the Atlantic cod, Gadus rnorhua.
Compo Biochem Physiol 99C: 11-14
5. Olson KR, DuffDW (1992) Cardiovascular and renal effects of eel and rat
atrial natriuretic peptide in rainbow trout, Sa/rno gairdneri. J Comp Physiol
B, 162: 408-415
6. Oudit GY, Butler DG (1995) Cardiovascular effects of arginine vasotocin,
atrial natriuretic peptide, and epinephrine in freshwater eels. Am J Physiol
268: RI273-RI280
7. Sverdrup A, Helle KB (1994) Different patterns of relaxation by atrial
natriuretic peptide in major blood vessels of two distantly related teleosts.
Reg Peptides, 53:89-101
211
of binding sites specific for both ANP and BNP, and interacting with
BNP at different affinities was observed in the mammalian heart [28,29].
Recently, pBNP was shown to specifically bind two types ofNPRs in the
rectal gland of the elasmobranch Squalus acanthias [30]. Although BNP
has not yet been identified in fish, its high sequence homology with
respect to the other piscine NPs [31] suggests that in the various cardiac
regions of both notothenioids, and particularly in the atrium of T
bernacchii, NP sites able to bind a BNP-like peptide exist.
Since homologous NPs from both T bernacchii and C. hamatus are not
available, caution must be exercised in analyzing the results using
heterologous ligands. However, the present data are of interest in
relation to the presence of a heterogeneous NP system in Antarctic
teleosts whose potential physiological significance needs to be further
investigated.
Acknowledgments
This research was supported by the Italian National Programme for Antarctic
Research (PNRA) (B. Tota).
References
1. Evans DH (1990) An emerging role for a cardiac peptide hormone in fish
osmoregulation. Ann. Rev. Physiol. 52: 43-60
2. Olson KR (1992) Blood and extracellular fluid volume regulation: role of
the renin-angiotensin system, kallykrein-kinin system, and atrial natriuretic
peptides. In: Fish physiology, Hoar WS, Randall DJ eds Academic Press
Inc Orlando, Florida, Vol XUB pp 135-254
3. Takei Y, Balment RJ (1993) Biochemistry and physiology of a family of
eel natriuretic peptides. Fish Physiol Biochem 11: 183-188
4. Acierno R, Axelsson A, Tota B, Agnisola C, Nilsson S (1991) Hypotensive
effect of atrial natriuretic factor (ANF) in the Atlantic cod, Gadus rnorhua.
Compo Biochem Physiol 99C: 11-14
5. Olson KR, DuffDW (1992) Cardiovascular and renal effects of eel and rat
atrial natriuretic peptide in rainbow trout, Sa/rno gairdneri. J Comp Physiol
B, 162: 408-415
6. Oudit GY, Butler DG (1995) Cardiovascular effects of arginine vasotocin,
atrial natriuretic peptide, and epinephrine in freshwater eels. Am J Physiol
268: RI273-RI280
7. Sverdrup A, Helle KB (1994) Different patterns of relaxation by atrial
natriuretic peptide in major blood vessels of two distantly related teleosts.
Reg Peptides, 53:89-101