• Anesthesia and analgesia · Jun 2000

    Propofol inhibits Ca(2+) transients but not contraction in intact beating guinea pig hearts.

    • Y Nakae, S Fujita, and A Namiki.
    • Department of Anesthesiology, Sapporo Medical University School of Medicine, Sapporo, Japan. yurinaka@sapmed.ac.jp
    • Anesth. Analg. 2000 Jun 1;90(6):1286-92.

    UnlabelledWe investigated whether propofol inhibits Ca(2+) transients and left ventricular pressure (LVP) in intact beating guinea pig hearts at clinical concentrations and whether an inhibition of Ca(2+) transients by propofol results from an impairment of sarcolemmal or of sarcoplasmic reticulum (SR) function. By using a Langendorff's preparation, transmural left ventricular phasic intracellular Ca(2+) concentration ([Ca(2+)](i)) was measured by the fluorescence ratio of indo-1 emission at 385 nm and 456 nm and was calibrated to Ca(2+) transients (in nM). The Ca(2+) transients during each contraction were defined as available [Ca(2+)](i). Sixty hearts were perfused with modified Krebs-Ringer's solution containing lipid vehicle and propofol (1 and 10 microM) in the absence and presence of ryanodine, thapsigargin, and nifedipine, while developed LVP and available [Ca(2+)](i) were recorded. Propofol (10 microM) decreased available [Ca(2+)](i) by 11.0% +/- 1.3% without decreasing developed LVP (% of control, P < 0.05). Propofol (10 microM) caused a leftward shift in the curve of developed LVP as a function of available [Ca(2+)](i). Propofol (10 microM) with nifedipine (1 microM), but not with ryanodine (1 microM) or thapsigargin (1 microM), decreased available [Ca(2+)](i) by 15.5% +/- 1.7% (P < 0.05). Propofol decreases available [Ca(2+)](i) without decreasing cardiac contraction, and it enhances myofilament Ca(2+) sensitivity in intact beating hearts at clinical concentrations. The inhibition of available [Ca(2+)](i) by propofol may be mainly mediated by an impairment of sarcoplasmic reticulum Ca(2+) handling rather than the sarcolemmal L-type Ca(2+) current.ImplicationsThis is the first study of the effects of propofol on intracellular Ca(2+) concentration and myofilament Ca(2+) sensitivity under physiologic conditions in intact isolated beating guinea pig hearts.

      Pubmed     Full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…