水素クリアランス法による肝組織血流量測定—経門脈・経肝動脈および経気管的水素負荷の比較

Hepatic blood flow by the hydrogen clearance method:Estimation of the routes for hydrogen administration

　水素クリアランス法に基く局所組織血流量の測定は1964年Auklandら^1）によって報告され，現在，脳，心筋，消化管，腎などに広く応用されている。肝は，動脈及び門脈から二重の血行をうけ，他臓器のように単純に本法を応用することには問題がある。そこで，理論的工夫^2）や電解式水素クリアランス計の応用などが試みられているが，未だ満足のいくものはない。

　著者らは，水素で飽和した生理食塩水（以下H_2-salineと略す）を直接門脈内又は肝動脈内に注入して得られる肝組織血流量（以下HBFと略す）が，より理論的HBFであると考え，従来の吸入法による値と比較検討した。

The different routes for hydrogen administration in the clearance method were evaluated in the measurement of hepatic blood flows. Seven mongrel dogs were used in this experiment. Four routes for hydrogen administration were intended in each dog anesthetized with GOF: 1)10% hydrogen gas inhala-tion accompanying with bolus injection of 40ml isotonic saline into the portal vein (Group I) , 2) 10% hydrogen-gas inhalation (Group II) , 3) bolus injection of 40ml hydrogen saturated isotonic saline into the portal vein (Group III), and 4) into the hepatic artery (Group IV). The hepatic blood flows were 57.4±13.7ml/min/100g in Group I, 56.5± 10.4ml, min/100g in Group II, 97.5±23.0ml/ min 100g in group III, and 95.7±19.7ml/ min 100 g in Group IV. The values of Group III and IV were significantly (p<0.005) higher than those in Groups I and II, and closely similar to reported ones obtained in a direct method by an electro-magnetic flow meter. We conclude that hepatic blood flows obtained by bolus injection of hydrogen saturated isotonic saline into the portal vein or the hepatic artery may be more accurate than those by hydrogen-gas inhalation.