Kallioniemi O P, Nieminen M M, Lehtinen J, Veneskoski T, Koivula T
Department of Clinical Chemistry, Tampere University Hospital, Finland.
Eur J Respir Dis. 1987 Sep;71(3):170-6.
To study the origin of increased serum placental-like alkaline phosphatase (PLAP-like) activity in smokers, heat stable alkaline phosphatase activity was assayed from serum and bronchoalveolar lavage (BAL) fluid in 83 smoking and non-smoking patients. PLAP-like activity was increased in about 80% of the smokers, independently of the underlying lung disease. Isoenzyme activities in BAL fluid correlated (r = 0.631, p less than 0.001) with serum values. When adjusted for the albumin concentration, mean PLAP-like activity in BAL fluid was almost 1000-fold higher than that in serum, suggesting local synthesis of PLAP-like isoenzymes in the lungs. Although a direct dose-response effect was not observed, the values in serum and in BAL fluid tended to be higher in patients smoking over 10 cigarettes daily as compared to patients smoking less. In ex-smokers the results indicated that PLAP-like activity decreased to the level observed in non-smokers within 5 years after cessation of smoking. PLAP activity was L-leucine sensitive compatible with the Nagao-variant type of PLAP in almost all cases. In three patients the activity was due to the L-leucine resistant (true placental) isoenzyme.
为研究吸烟者血清中胎盘样碱性磷酸酶（PLAP样）活性升高的来源，我们检测了83例吸烟和不吸烟患者血清及支气管肺泡灌洗（BAL）液中的热稳定碱性磷酸酶活性。约80%的吸烟者PLAP样活性升高，与潜在的肺部疾病无关。BAL液中的同工酶活性与血清值相关（r = 0.631，p < 0.001）。校正白蛋白浓度后，BAL液中PLAP样活性的平均值比血清中高近1000倍，提示肺部存在PLAP样同工酶的局部合成。虽然未观察到直接的剂量反应效应，但与每天吸烟少于10支的患者相比，每天吸烟超过10支的患者血清和BAL液中的值往往更高。对于戒烟者，结果表明戒烟后5年内PLAP样活性降至非吸烟者的水平。几乎在所有病例中，PLAP活性对L-亮氨酸敏感，与Nagao变异型PLAP一致。在3例患者中，活性是由L-亮氨酸抗性（真正的胎盘）同工酶引起的。
