Chronic exposure to low doses of HgCl2 avoids calcium handling impairment in the right ventricle after myocardial infarction in rats.
Chronic exposure to low doses of HgCl2 avoids calcium handling impairment in the right ventricle after myocardial infarction in rats.
复制标题
DOI：
10.1371/journal.pone.0095639
复制
发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Vassallo PF
中科院分区：
文献类型：
--
作者：
Faria Tde O;Costa GP;Almenara CC;Angeli JK;Vassallo DV;Stefanon I;Vassallo PF
右心室收缩功能障碍是心肌梗死（MI）后死亡和心力衰竭的主要危险因素。重金属暴露与多种心血管疾病（例如心肌梗死）的发生有关。本研究的目的是调查长期接触低剂量氯化汞 (HgCl2) 是否会加剧 MI 后右心室条带的功能恶化。将雄性 Wistar 大鼠分为四组：对照组（媒介物）； HgCl2（4 周内暴露 - 第 1 剂 4.6 µg/kg，后续剂量 0.07 µg/kg/天，肌肉注射以弥补每日损失）； MI 手术诱导组和 HgCl2-MI 组。 MI后一周，研究右心室条带的形态学和血流动力学测量以及等长张力。在评估的形态学或血流动力学参数中，与单独的 MI 相比，慢性 HgCl2 暴露并没有加重损伤。在基础条件下，尽管 L-max 的最大等长力相似，但与对照组相比，MI 组的松弛时间有所增加，但 HgCl2-MI 组的松弛时间不受影响。在 MI 组中观察到肌浆网 (SR) 功能受损和肌膜钙流入减少，这与 SERCA2a 减少和 PLB 蛋白表达增加相关。慢性 HgCl2 暴露大鼠中的 MI 诱导不会导致 L-max 产生的力、松弛功能或 -dF/dt 发生任何改变，除了 SR 功能降低的趋势之外。这些发现可以部分解释为仅在该组中观察到的肌膜钙流入正常化和 NCX 蛋白表达增加。这些结果表明，长期暴露于低剂量的 HgCl2 可能通过作用于 NCX、PLB 和 SERCA2a 蛋白表达来防止 MI 中观察到的 SR 功能受损和肌膜钙流入减少。
Right ventricle systolic dysfunction is a major risk factor for death and heart failure after myocardial infarction (MI). Heavy metal exposure has been associated with the development of several cardiovascular diseases, such as MI. The aim of this study was to investigate whether chronic exposure to low doses of mercury chloride (HgCl2) enhances the functional deterioration of right ventricle strips after MI. Male Wistar rats were divided into four groups: Control (vehicle); HgCl2 (exposure during 4 weeks- 1st dose 4.6 µg/kg, subsequent dose 0.07 µg/kg/day, i.m. to cover daily loss); MI surgery induced and HgCl2-MI groups. One week after MI, the morphological and hemodynamic measurements and isometric tension of right ventricle strips were investigated. The chronic HgCl2 exposure did not worsen the injury compared with MI alone in the morphological or hemodynamic parameters evaluated. At basal conditions, despite similar maximum isometric force at L-max, relaxation time was increased in the MI group but unaffected in the HgCl2-MI compared to the Control group. Impairment of the sarcoplasmic reticulum (SR) function and reduction in the sarcolemmal calcium influx were observed in MI group associated with SERCA2a reduction and increased PLB protein expression. Induction of MI in chronic HgCl2 exposed rats did not cause any alteration in the developed force at L-max, lusitropic function or −dF/dt except for a tendency of a reduction SR function. These findings could be partially explained by the normalization in the sarcolemmal calcium influx and the increase in NCX protein expression observed only in this group. These results suggest that chronic exposure to low doses of HgCl2 prevents the impaired SR function and the reduced sarcolemmal calcium influx observed in MI likely by acting on NCX, PLB and SERCA2a protein expression.
登录
查看更多内容
与高血压发育无关，急性暴露于铅增加心肌收缩力。
DOI：
10.1590/1414-431x20122190
发表时间：
2013-02
期刊：
Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas
影响因子：
--
作者：
Fioresi M;Furieri LB;Simões MR;Ribeiro RF Jr;Meira EF;Fernandes AA;Stefanon I;Vassallo DV
通讯作者：
Vassallo DV
影响因子：
8.3
作者：
Park, Sung Kyun;Lee, Sunghee;Basu, Niladri;Franzblau, Alfred
通讯作者：
Franzblau, Alfred
影响因子：
20.1
作者：
PFEFFER, MA;PFEFFER, JM;BRAUNWALD, E
通讯作者：
BRAUNWALD, E
DOI：
10.1016/s1532-0456(03)00110-8
发表时间：
2003-07-01
影响因子：
3.9
作者：
Moreira, CM;Oliveira, EM;Vassallo, DV
通讯作者：
Vassallo, DV
影响因子：
10.4
作者：
CLARKSON, TW
通讯作者：
CLARKSON, TW