Junila J, Huttunen P, Kaarela O, Waris T
Department of Surgery, Oulu University Central Hospital, Finland.
Cryobiology. 1992 Dec;29(6):674-8. doi: 10.1016/0011-2240(92)90070-i.
The aim of this study was to investigate the development of the demarcation line in the rabbit ear upon injury by experimental freezing and thawing. For this purpose the sequential changes in noradrenaline (NA) content in the tissue and nerve of the ear were determined by liquid chromatography. Frostbite was inflicted with a glass bottle filled with liquid nitrogen and specimens were taken from the injured area, the probable demarcation line area and the healthy area 1, 3, and 7 days after frostbite. Control samples were taken from the normal contralateral ear. Tissue NA levels in the injured area and the probable demarcation line area were significantly lower than those in corresponding areas of the control ear after 1 day. Day 3 NA levels in the demarcation line area were 90% higher than those on Day 1 in this area and were not significantly different from Day 3 levels in the control ear. By Day 7, NA levels in the demarcation line area were down to 70% of the Day 3 levels. NA levels in the central nerve at the probable demarcation line were much higher than those in the control ear nerve and also showed a peak on Day 3. In conclusion, the results suggest that NA is released from the adrenergic nerves and the reaction at the probable demarcation line is strongest on the third day.
本研究的目的是通过实验性冻融来研究兔耳损伤后分界线的发展情况。为此，采用液相色谱法测定耳部组织和神经中去甲肾上腺素（NA）含量的连续变化。用装满液氮的玻璃瓶造成冻伤，并在冻伤后1天、3天和7天从损伤区域、可能的分界线区域和健康区域采集标本。对照样本取自对侧正常耳朵。冻伤后1天，损伤区域和可能的分界线区域的组织NA水平显著低于对照耳相应区域。在分界线区域，第3天的NA水平比该区域第1天的水平高90%，且与对照耳第3天的水平无显著差异。到第7天，分界线区域的NA水平降至第3天水平的70%。可能的分界线处中枢神经中的NA水平远高于对照耳神经中的水平，且在第3天也出现峰值。总之，结果表明NA从肾上腺素能神经释放，且在可能的分界线处第3天的反应最强。
