動脈壁トリブチリン水解酵素の研究

抄録

Recently from our laboratory, it has been reported that serum nonspecific carboxyl esterase (tributyrin hydrolase) might be converted to lipase (triolein hydrolase) in aorta.
In the present report, the characteristic of tributyrin hydrolase in rat arterial wall were elucidated in order to clarify the mechanism of conversion from esterase to lipase.
Tributyrin hydrolase activity was estimated in homogenate of rat arterial wall using glyceryl tri[1-¹⁴C]butyrate as a substrate.
Optimum pH was found broadly from 6.0 to 9.0. Ca²⁺, Mg²⁺ or Ni²⁺ inhibited the tributyrin hydrolase activity by 20-30%. Zn²⁺ or Na⁺ inhibited the activity by 30-40%. Cu²⁺ inhibited the activity by 70%. Mn²⁺ or Ba²⁺ had no effect on the activity. HDL increased tributyrin hydrolase activity to the extent of 160%. VLDL or LDL or apo C-II or apo C-III had no effect on the activity.