小柯机器人

美国哈佛大学Adam E. Cohen等研究人员合作发现，一种生物电相变形成首次脊椎动物的心跳。这一研究成果于2023年9月27日在线发表在国际学术期刊《自然》上。

研究人员利用全光学电生理学捕获了斑马鱼的第一次心跳，并分析了围绕这一奇特事件的心脏兴奋性和传导的发展。最初的几次搏动突然出现，搏动间歇不规则，在原始心脏中连贯传播，而且发出搏动的位置因动物和时间而异。由Ca_V1.2驱动的动作电位上冲在不变圆分叉上的鞍节点噪声很好地描述了生物电动态。这项研究表明，单细胞生物电特性的渐进和基本不同步发展如何产生从静止到协调搏动的刻板和稳健的组织尺度过渡。

研究人员表示，规律的心跳对脊椎动物的生命至关重要。在成熟的心脏中，这一功能是由解剖定位的起搏器驱动的。相比之下，起搏能力在早期胚胎心脏中广泛分布，这就提出了一个问题：在胚胎发育过程中，组织尺度的活动是如何首先建立然后维持的？从单个电事件的时间尺度来看，心脏从无声到跳动的最初过渡从未被表征过，人们对早期心跳的空间和时间结构仍然知之甚少。

附：英文原文

Title: A bioelectrical phase transition patterns the first vertebrate heartbeats

Author: Jia, Bill Z., Qi, Yitong, Wong-Campos, J. David, Megason, Sean G., Cohen, Adam E.

Issue&Volume: 2023-09-27

Abstract: A regular heartbeat is essential to vertebrate life. In the mature heart, this function is driven by an anatomically localized pacemaker. By contrast, pacemaking capability is broadly distributed in the early embryonic heart1,2,3, raising the question of how tissue-scale activity is first established and then maintained during embryonic development. The initial transition of the heart from silent to beating has never been characterized at the timescale of individual electrical events, and the structure in space and time of the early heartbeats remains poorly understood. Using all-optical electrophysiology, we captured the very first heartbeat of a zebrafish and analysed the development of cardiac excitability and conduction around this singular event. The first few beats appeared suddenly, had irregular interbeat intervals, propagated coherently across the primordial heart and emanated from loci that varied between animals and over time. The bioelectrical dynamics were well described by a noisy saddle-node on invariant circle bifurcation with action potential upstroke driven by CaV1.2. Our work shows how gradual and largely asynchronous development of single-cell bioelectrical properties produces a stereotyped and robust tissue-scale transition from quiescence to coordinated beating.

DOI: 10.1038/s41586-023-06561-z

Source: https://www.nature.com/articles/s41586-023-06561-z

Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
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