肺炎球菌孵育的血浆对乳头肌收缩力的抑制作用。

Depression of papillary muscle contractility by plasma incubated with pneumococci.

作者信息

Reed W P, Leach J K, Chick T W, Goldblum S E, Albright E, Chavez R P

出版信息

Am Heart J. 1986 Jul;112(1):84-8. doi: 10.1016/0002-8703(86)90683-6.

Abstract

Mechanisms of death in pneumococcal disease are poorly understood. We have previously shown that intravenous pneumococcal products in dogs caused a mean decrease in cardiac output of 58%. The present study used measurements of the force and rate of contraction of isolated rabbit papillary muscle to determine whether pneumococci (PNC) altered myocardial contractility. Nine papillary muscles were superfused with various solutions including Tyrode's, Tyrode's incubated with sonicated type 1 PNC, normal rabbit plasma, and rabbit plasma incubated with PNC. Compared to untreated Tyrode's solution, PNC-treated Tyrode's solution did not alter papillary muscle contractility. However, compared to untreated rabbit plasma, plasma incubated with PNC caused a mean decrease of 18% in the force of contraction and 16.7% in the maximum rate of force development in nine studies. We conclude that PNC do not directly affect papillary muscle contractility. However, the interaction of PNC and plasma does cause a decrease in rabbit papillary muscle contractility.

摘要

肺炎球菌疾病的死亡机制尚不清楚。我们之前已表明，给犬静脉注射肺炎球菌制剂会使心输出量平均下降58%。本研究通过测量离体兔乳头肌的收缩力和收缩速率，以确定肺炎球菌（PNC）是否会改变心肌收缩力。九条乳头肌用不同溶液进行灌流，这些溶液包括台氏液、与经超声处理的1型PNC一起孵育的台氏液、正常兔血浆以及与PNC一起孵育的兔血浆。与未处理的台氏液相比，经PNC处理的台氏液并未改变乳头肌收缩力。然而，在九项研究中，与未处理的兔血浆相比，与PNC一起孵育的血浆使收缩力平均下降了18%，使最大力发展速率下降了16.7%。我们得出结论，PNC不会直接影响乳头肌收缩力。然而，PNC与血浆的相互作用确实会导致兔乳头肌收缩力下降。