Naunyn Schmiedebergs Arch Pharmacol. 2013 Aug;386(8):665-70. doi: 10.1007/s00210-013-0874-z. Epub 2013 May 7.
Elucidation of cAMP and cGMP signalling in the heart remains a hot topic, and new regulatory mechanisms continue to appear. Studying the influence of phosphodiesterases on 5-HT4 receptor signalling in porcine atrium, a paper from this issue of the journal expands findings of a crosstalk between cardiac cGMP and cAMP signalling recently discovered in failing rat ventricle to a different species and cardiac region. The overall data suggest that cGMP, produced following stimulation of the NPR-B receptor for C-type natriuretic peptide (CNP), inhibits cAMP degradation by phosphodiesterase 3 and thereby enhances cAMP-mediated signalling from β-adrenoceptors and 5-HT4 receptors to inotropic effects. In porcine atrium, this effect can be seen both as an increase in inotropic effect and as a reduced fade of the inotropic effect with time. Thus, accumulating evidence brings together several active fields of research, including cardiac phosphodiesterases, compartmentation of cyclic nucleotide signalling and the field of natriuretic peptides. If present in human hearts, this effect of CNP may have clinical implications.
环磷酸腺苷（cAMP）和环磷酸鸟苷（cGMP）信号在心脏中的阐明仍然是一个热门话题，新的调节机制不断出现。本期杂志中的一篇论文研究了磷酸二酯酶对猪心房 5-羟色胺 4 受体信号的影响，该论文将最近在衰竭的大鼠心室中发现的心脏 cGMP 和 cAMP 信号之间的串扰扩展到了不同物种和心脏区域。总体数据表明，在 C 型利钠肽（CNP）的 NPR-B 受体被刺激后产生的 cGMP 抑制磷酸二酯酶 3 降解 cAMP，从而增强了β肾上腺素能受体和 5-羟色胺 4 受体介导的 cAMP 信号转导对心肌收缩力的作用。在猪心房中，这种作用既可以表现为心肌收缩力的增加，也可以表现为心肌收缩力随时间的衰减减少。因此，越来越多的证据将包括心脏磷酸二酯酶、环核苷酸信号转导区室化和利钠肽领域在内的几个活跃的研究领域联系在一起。如果这种 CNP 的作用存在于人类心脏中，可能具有临床意义。
