Meffert M K, Haley J E, Schuman E M, Schulman H, Madison D V
Department of Neurobiology, Stanford University Medical Center, California 94305.
Neuron. 1994 Nov;13(5):1225-33. doi: 10.1016/0896-6273(94)90060-4.
Four potent metalloporphyrin inhibitors of heme oxygenase were used to assess whether carbon monoxide production was required for induction of LTP in the CA1 region of the hippocampus. Although the metalloporphyrins produced a similar and substantial inhibition of heme oxygenase activity in hippocampal slices, only two compounds reduced the amount of LTP elicited by tetanic stimulation (chromium mesoporphyrin IX and zinc protoporphyrin IX). Both chromium mesoporphyrin IX and zinc protoporphyrin IX inhibited nitric oxide synthase in the hippocampus; tin mesoporphyrin IX and zinc deuteroporphyrin IX bis glycol neither reduced LTP induction nor inhibited NOS activity, although they did inhibit heme oxygenase. None of these metalloporphyrins reversed established LTP. Thus, together these data do not support carbon monoxide as a mediator in either LTP induction or expression/maintenance and emphasize further the nonselectivity of some metalloporphyrins.
使用四种有效的血红素加氧酶金属卟啉抑制剂来评估海马体CA1区中长时程增强（LTP）的诱导是否需要一氧化碳的产生。尽管金属卟啉对海马切片中的血红素加氧酶活性产生了相似且显著的抑制作用，但只有两种化合物减少了强直刺激引发的LTP量（中卟啉铬IX和原卟啉锌IX）。中卟啉铬IX和原卟啉锌IX均抑制海马体中的一氧化氮合酶；中卟啉锡IX和双乙二醇氘代锌卟啉IX既未降低LTP诱导，也未抑制一氧化氮合酶活性，尽管它们确实抑制了血红素加氧酶。这些金属卟啉均未逆转已建立的LTP。因此，这些数据共同不支持一氧化碳作为LTP诱导或表达/维持的介质，并进一步强调了某些金属卟啉的非选择性。
