可卡因和去甲肾上腺素对新生大鼠心肌细胞原代培养物的影响。

Welder A A, Eselin J A, Melchert R B, Davis S K, O'Dell J F

College of Pharmacy, University of Oklahoma Health Sciences Center, Oklahoma City 73190.

J Toxicol Environ Health. 1992 Jun;36(2):75-90. doi: 10.1080/15287399209531626.

Sudden cardiac death associated with cocaine (Coc) abuse in healthy, physically active individuals became a grave concern in the late 1980s. It is well documented that physical activity increases circulating plasma catecholamine levels. Catecholamines as well as Coc are independently capable of inducing toxic cardiac effects. The purpose of this investigation was to evaluate the synergistic or additive toxic effects of norepinephrine (NE) and Coc in primary myocardial cell cultures obtained from 3- to 5-d-old Sprague-Dawley rats. Alterations in lactate dehydrogenase release (LDH), lysosomal neutral red retention (NR), beating activity, and morphology were evaluated after treatment of the cells for 1-24 h with 1 x 10(-3) M Coc alone, 1 x 10(-5) M Coc alone, 1 x 10(-5) M NE alone, 1 x 10(-3) M Coc with 1 x 10(-5) M NE, or 1 x 10(-5) M Coc with 1 x 10(-5) M NE. LDH release was elevated significantly after 24 h only with those cells exposed to 1 x 10(-3) M Coc alone and 1 x 10(-3) M Coc + 1 x 10(-5) M NE. Using NR retention as a score for lysosomal treatment of the cells with 1 x 10(-5) M Coc and 1 x 10(-3) M Coc alone did not decrease dye retention significantly. However, 1 x 10(-5) M NE combined with 1 x 10(-3) M Coc significantly reduced lysosomal dye retention as early as 1 h after treatment. After 24 h, 1 x 10(-5) M NE alone and 1 x 10(-5) M NE combined with 1 x 10(-5) M Coc significantly increased lysosomal fragility. Beating activity was altered in all treatment groups. Contractile activity was slow and irregular or completely absent with 1 x 10(-5) and 1 x 10(-3) M Coc, respectively. When NE (1 x 10(-5) M) was combined with both concentrations of Coc, there was distinct focalization of sharp, rapid contractions within the cells, which were asynchronous and/or arrhythmic in nature. Those cells exposed to 1 x 10(-5) M NE with 1 x 10(-5) M Coc for 24 h appeared hypercontracted with marked pseudopodia and cytoplasmic granule formation distinctly different from that exhibited by the cells exposed to 1 x 10(-5) M Coc alone. These data demonstrate that NE potentiates the adverse effects of Coc on contractile activity and morphology of spontaneously contracting neonatal myocardial cells maintained in culture.

20世纪80年代末，健康且经常运动的个体因滥用可卡因（Coc）导致的心源性猝死成为一个严重问题。有充分文献记载，体育活动会使循环血浆儿茶酚胺水平升高。儿茶酚胺以及可卡因都能独立诱发毒性心脏效应。本研究的目的是评估去甲肾上腺素（NE）和可卡因对从3至5日龄Sprague-Dawley大鼠获取的原代心肌细胞培养物的协同或相加毒性作用。在用1×10⁻³ M可卡因单独处理、1×10⁻⁵ M可卡因单独处理、1×10⁻⁵ M去甲肾上腺素单独处理、1×10⁻³ M可卡因与1×10⁻⁵ M去甲肾上腺素联合处理或1×10⁻⁵ M可卡因与1×10⁻⁵ M去甲肾上腺素联合处理细胞1至24小时后，评估乳酸脱氢酶释放（LDH）、溶酶体中性红保留（NR）、搏动活性和形态的变化。仅在那些单独暴露于1×10⁻³ M可卡因和1×10⁻³ M可卡因 + 1×10⁻⁵ M去甲肾上腺素的细胞中，24小时后LDH释放显著升高。以NR保留作为细胞溶酶体处理的评分，单独用1×10⁻⁵ M可卡因和1×10⁻³ M可卡因处理并未显著降低染料保留。然而，1×10⁻⁵ M去甲肾上腺素与1×10⁻³ M可卡因联合处理在处理后1小时就显著降低了溶酶体染料保留。24小时后，单独的1×10⁻⁵ M去甲肾上腺素以及1×10⁻⁵ M去甲肾上腺素与1×10⁻⁵ M可卡因联合处理显著增加了溶酶体脆性。所有处理组的搏动活性均发生改变。收缩活性分别在1×10⁻⁵和1×10⁻³ M可卡因处理下缓慢且不规则或完全消失。当去甲肾上腺素（1×10⁻⁵ M）与两种浓度的可卡因联合时，细胞内出现明显的尖锐、快速收缩的局灶化，这些收缩本质上是异步和/或心律失常的。暴露于1×10⁻⁵ M去甲肾上腺素与1×10⁻⁵ M可卡因24小时的那些细胞出现过度收缩，伴有明显的伪足和细胞质颗粒形成，与单独暴露于1×10⁻⁵ M可卡因的细胞表现明显不同。这些数据表明，去甲肾上腺素增强了可卡因对培养的自发收缩新生心肌细胞的收缩活性和形态的不利影响。