Parkes D G, Coghlan J P, Scoggins B A
Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Australia.
Life Sci. 1989;45(24):2303-12. doi: 10.1016/0024-3205(89)90112-4.
The rapid hemodynamic effects of several N- and C-terminal deleted fragments of ANF, a potent ANF analogue and the recently characterised brain natriuretic peptide (BNP) were investigated in conscious sheep, and compared to the rapid hemodynamic actions of ANF 1-28. The hypotensive potency of all peptides studied was as follows: ANF 1-28 = PLO58 greater than 5-27 = ANF 5-28 = BNP greater than ANF 7-28 greater than ANF 13-28 = ANF 5-25. All peptides reduced blood pressure via a decrease in total peripheral resistance, excluding ANF 5-25 and 13-28 which were without effect on any parameter measured. These changes were associated with reflex increases in both heart rate and cardiac output, and a slight reduction in stroke volume. The duration of hypotensive/vasodilator action of ANF 1-28, 5-27, 5-28, 7-28 and BNP was approximately 3-4 minutes, whereas that of PLO58 was 7-8 minutes. In conclusion, amino acid deletions from the C- and N-terminal of the ANF molecule reduced the hypotensive/vasodilator potency of the peptide in conscious sheep. BNP produced similar rapid hemodynamic changes to ANF 1-28, suggesting that the two peptides may co-regulate blood pressure and possibly body fluids to promote fluid and cardiovascular homeostasis.
