Posselt A M, Kwong L K, Vreman H J, Stevenson D K
Am J Dis Child. 1986 Feb;140(2):147-50. doi: 10.1001/archpedi.1986.02140160065034.
The effect of a single prophylactic dose of tin protoporphyrin on the carbon monoxide (CO) excretion rate of antibiotic-treated neonatal rats before and after hematoma formation was evaluated. The CO excretion rate, reflecting the rate of bilirubin production, of tin protoporphyrin-treated (TP-H) rats 24 hours after injection of 65 mole of tin protoporphyrin per kilogram (time [t] = 0 hours) was approximately 18% lower than those of the saline-control (S-C) and saline-hematoma (S-H) rats, but this difference was no longer evident at t = 43 hours. After hematoma formation at t = 44 hours, the CO excretion rate of the S-H rats increased rapidly; this increase was delayed and lessened in the TP-H rats. At eight hours posthematoma (t = 52 hours), the CO excretion rate of the TP-H rats was significantly lower than that of the S-H rats, 53 +/- 2 vs 73 +/- 3 microL/kg/hr, respectively. A maximal rate of 89 +/- 5 microL/kg/hr was reached 25 hours posthematoma in the S-H rats (t = 69 hours), as compared with 80 +/- 3 microL/kg/hr at 44 hours posthematoma in the TP-H rats (t = 88 hours). The recovery of injected blood as CO over a 68-hour study period was approximately 90% for the S-H rats and approximately 65% for the TP-H rats. At t = 112 hours, hepatic heme oxygenase activity of the TP-H rats was still significantly lower than that of the S-H and S-C rats; however, plasma bilirubin concentrations of all three groups were similar. These studies demonstrate that tin protoporphyrin is an effective in vivo inhibitor of endogenous heme catabolism as measured by the CO excretion rate in antibiotic-treated neonatal rats with and without artificially created hematomas.
评估了单次预防性剂量的锡原卟啉对血肿形成前后接受抗生素治疗的新生大鼠一氧化碳（CO）排泄率的影响。每千克注射65微摩尔锡原卟啉（时间[t]=0小时）后24小时，经锡原卟啉处理（TP-H）的大鼠的CO排泄率反映胆红素生成速率，比生理盐水对照（S-C）和生理盐水-血肿（S-H）大鼠低约18%，但在t = 43小时时这种差异不再明显。在t = 44小时形成血肿后，S-H大鼠的CO排泄率迅速增加；TP-H大鼠的这种增加延迟且减弱。血肿形成后8小时（t = 52小时），TP-H大鼠的CO排泄率显著低于S-H大鼠，分别为53±2与73±3微升/千克/小时。S-H大鼠在血肿形成后25小时（t = 69小时）达到最大速率89±5微升/千克/小时，而TP-H大鼠在血肿形成后44小时（t = 88小时）为80±3微升/千克/小时。在68小时的研究期内，S-H大鼠注射血液作为CO的回收率约为90%，TP-H大鼠约为65%。在t = 112小时，TP-H大鼠的肝血红素加氧酶活性仍显著低于S-H和S-C大鼠；然而，三组的血浆胆红素浓度相似。这些研究表明，通过在有或没有人工制造血肿的抗生素治疗新生大鼠中测量CO排泄率，锡原卟啉是内源性血红素分解代谢的有效体内抑制剂。
