Ishii Yukimoto, Asai Satoshi, Kohno Tadashi, Ito Asuka, Iwai Shigetomi, Ishikawa Koichi
Departments of Pharmacology and Third Department of Surgery, Nihon University School of Medicine, Itabashi-ku, Tokyo, Japan.
Surgery. 2002 Nov;132(5):849-56. doi: 10.1067/msy.2002.127947.
We have previously reported that by means of a breath test with intravenously administered L-[1-13C] phenylalanine (13Cphe), hepatopathy could be quantitatively evaluated by measuring expiratory 13CO2 levels in a short period. It is known that phenylalanine hydroxylase activity (PAHA) plays an important role in phenylalanine metabolism. We examined the relationship between changes in PAHA and the results of the 13Cphe breath test during hepatic regeneration in a rat model of 70% hepatectomy, to assess their usefulness for evaluating hepatic regeneration.
Male Wistar rats (Shizvoka Laboratory Animal Center, Hamamatsu, Japan) weighing 230 to 290 g were subjected to 70% hepatectomy under anesthesia with sodium pentobarbital. One, 2, 3, 5, 7, and 14 days postoperatively, 30 mg/kg 13Cphe was intravenously injected into the femoral vein, and the increase in exhaled 13CO2 (Delta 13CO2) was measured for 15 minutes. Simple laparotomy was performed in control rats. After the breath test, the regenerated liver was removed and weighed. The amount of DNA, amount of hepatic tissue total protein (TP), and PAHA were determined.
The r between liver weight/body weight and PAHA, between DNA and PAHA, and between TP and PAHA were 0.832, 0.720, and 0.758, respectively. Breath test graphs revealed that liver weight/body weight, DNA, and TP showed the best correlations with the peak value of Delta 13CO2 (liver weight/body weight percentage, r = 0.801; DNA, r = 0.660; TP, r = 0.706), and r between PAHA and peak value was 0.638.
These results suggest that measurement of PAHA in regenerated liver is an effective method for following up liver function after hepatic resection. Moreover, the 13Cphe breath test may also be useful to evaluate liver function after partial hepatectomy.
我们之前报道过，通过静脉注射L-[1-¹³C]苯丙氨酸（¹³Cphe）进行呼气试验，可在短时间内通过测量呼出的¹³CO₂水平对肝病进行定量评估。已知苯丙氨酸羟化酶活性（PAHA）在苯丙氨酸代谢中起重要作用。我们在70%肝切除大鼠模型的肝再生过程中，研究了PAHA变化与¹³Cphe呼气试验结果之间的关系，以评估它们在评估肝再生方面的实用性。
体重230至290克的雄性Wistar大鼠（日本滨松市Shizvoka实验动物中心）在戊巴比妥钠麻醉下接受70%肝切除术。术后1、2、3、5、7和14天，将30毫克/千克的¹³Cphe静脉注射到股静脉中，并测量15分钟内呼出的¹³CO₂增加量（Δ¹³CO₂）。对照大鼠进行单纯剖腹手术。呼气试验后，取出再生肝脏并称重。测定DNA含量、肝组织总蛋白（TP）含量和PAHA。
肝重/体重与PAHA之间、DNA与PAHA之间以及TP与PAHA之间的r分别为0.832、0.720和0.758。呼气试验图显示，肝重/体重、DNA和TP与Δ¹³CO₂峰值的相关性最佳（肝重/体重百分比，r = 0.801；DNA，r = 0.660；TP，r = 0.706），PAHA与峰值之间的r为0.638。
这些结果表明，测量再生肝脏中的PAHA是肝切除术后肝功能随访的有效方法。此外，¹³Cphe呼气试验可能也有助于评估部分肝切除术后的肝功能。
