Atrial natriuretic peptide stimulates Na+‐dependent Ca2+ efflux from freshly isolated adult rat cardiomyocytes

FEBS Letters

Houchi, Hitoshi²  Kitagawa, Tetsuya¹  Tamaki, Toshiaki²  Horike, Kazuya¹  Tsuchiya, Koichiro²  Katoh, Itsuo¹  Minakuchi, Kazuo²  Yoshizumi, Masanori² 

[1] Department of Cardiovascular Surgery, University of Tokushima School of Medicine, Tokushima 770, Japan;Department of Pharmacology, University of Tokushima School of Medicine, Tokushima 770, Japan

关键词: Atrial natriuretic peptide;    Ca2+ efflux;    Na+/Ca2+ exchange;    Guanosine 3′;    5′-cyclic monophosphate;    Natriuretic peptide receptor;    Cardiomyocyte;    ANP;    atrial natriuretic peptide;    BNP;    brain natriuretic peptide;    CNP;    C-type natriuretic peptide;    cGMP;    guanosine 3′;    5′-cyclic monophosphate;    [Ca2+]i;    cytosolic free calcium concentration;    K-H solution;    Krebs-Henseleit bicarbonate buffer solution;    NPR;    natriuretic peptide receptor;   

DOI  :  10.1016/S0014-5793(97)01470-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In the present study, we examined the effect of atrial natriuretic peptide (ANP) on Ca²⁺ efflux from freshly isolated adult rat cardiomyocytes. Rat ANP(1–28) stimulated the efflux of ⁴⁵Ca²⁺ from the cells in a concentration-dependent manner (10⁻⁸ M to 10⁻⁶ M). The ⁴⁵Ca²⁺ efflux was not affected by removal of extracellular Ca²⁺, but was dependent on the presence of extracellular Na⁺. In addition, rat ANP(1–28) caused ²²Na⁺ influx into the cells. The ⁴⁵Ca²⁺ efflux was also stimulated by C-type natriuretic peptide-22 (CNP-22), but not by rat brain natriuretic peptide-45 (BNP-45). It was also observed that both rat ANP(1–28) and CNP-22 stimulated guanosine 3′,5′-cyclic monophosphate production within the cells. These results indicate that ANP stimulates Na⁺-dependent ⁴⁵Ca²⁺ efflux from freshly isolated adult rat cardiomyocytes, probably through Na⁺/Ca²⁺ exchange, and that the stimulatory effect of ANP on Ca²⁺ efflux may be mediated via the natriuretic peptide receptor which has been shown to couple to guanylate cyclase. Since it is reported that Na⁺/Ca²⁺ exchange is important in calcium homeostasis within cells, ANP may play a role in the extrusion of intracellular Ca²⁺ from isolated adult rat cardiomyocytes.

【 授权许可】

Unknown