Presence of dendroaspis natriuretic peptide and its binding to NPR-A receptor in rabbit kidney.
Natriuretic peptides help to maintain sodium and fluid volume homeostasis in a healthy cardio-renal environment. Since the identification of Dendroaspis natriuretic peptide (DNP) as a new member of the natriuretic peptide family, DNP has been considered as an important regulator of natriuresis and dieresis. The present study was undertaken to investigate the presence of immunoreactive Dendroaspis natriuretic peptide (DNP) and its specific receptor in rabbit. DNP was detected in heart, kidney, liver, brain, and plasma by radioimmunoassay (RIA). DNP contents of cardiac atrium and ventricle, renal cortex and medulla, liver, and brain were 1.42 ± 0.15, 1.0 6 ± 0.08, 2.55 ± 0.21, 1.81 ± 0.16, 1.36 ± 0.22, and 0.69 ± 0.15 pg/mg of wet weight, respectively. The concentration of DNP in plasma was 235.44 ± 15.44 pg/ml. By quantitative in vitro receptor autoradiography, specific ¹²⁵I-DNP binding sites were revealed in glomeruli, interlobular artery, acuate artery, vasa recta bundle, and inner medulla of the kidney with an apparent dissociation constant (K(d)) of 0.29 ± 0.05, 0.36 ± 0.03, 0.84 ± 0.19, 1.18 ± 0.23, and 10.91 ± 1.59 nM, respectively. Basal rate of 3', 5'-cyclic guanosine monophosphate (cGMP) production by particulate guanylyl cyclase (GC) activation of glomerular membranes was basally 13.40 ± 1.70 pmol/mg protein/min. DNP caused an increment of cGMP production in similar magnitude to that caused by ANP, BNP, and urodilatin, while the production of cGMP by CNP was significantly lower than that by DNP. Our results show that plasma levels of DNP were higher when compared to other tissues. DNP produces cGMP via the NPR-A receptor subtype in the kidney, similarly to ANP and BNP, suggesting that plasma DNP could have similar functions as ANP and BNP.
Department of Physiology, Institute for Medical Sciences, Center for Healthcare Technology Development, Chonbuk National University Medical School, Jeonju 561-180, Republic of Korea.
Soo Mi
SM
Kim
Yoon Ah
YA
Kim
Sun Young
SY
Kim
Suhn Hee
SH
Kim
Kyung Woo
KW
Cho
Sung Zoo
SZ
Kim
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000032:analysis / Q000096:biosynthesis; D001345:Autoradiography; D001665:Binding Sites; D001921:Brain / Q000502:physiology / Q000648:ultrastructure; D006152:Cyclic GMP / Q000096:biosynthesis; D004231:Diuresis; D004546:Elapid Venoms / Q000097:blood / Q000652:urine; D006162:Guanylate Cyclase / Q000378:metabolism; D006321:Heart / Q000502:physiology; D036341:Intercellular Signaling Peptides and Proteins; D007668:Kidney / Q000502:physiology* / Q000648:ultrastructure; D008099:Liver / Q000502:physiology / Q000648:ultrastructure; D008297:Male; D009318:Natriuresis; D020097:Natriuretic Peptide, Brain / Q000032:analysis / Q000096:biosynthesis; D020098:Natriuretic Peptide, C-Type / Q000032:analysis / Q000096:biosynthesis; D010455:Peptides / Q000097:blood / Q000652:urine; D011485:Protein Binding; D011817:Rabbits; D011863:Radioimmunoassay; D017461:Receptors, Atrial Natriuretic Factor / Q000378:metabolism*
C075597:Dendroaspis natriuretic peptide; D004546:Elapid Venoms; D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; D020097:Natriuretic Peptide, Brain; D020098:Natriuretic Peptide, C-Type; D009320:Atrial Natriuretic Factor; D006162:Guanylate Cyclase; D017461:Receptors, Atrial Natriuretic Factor; D006152:Cyclic GMP