Affiliations: Department of Hepato-Biliary-Pancreatic Surgery, Osaka
City University Graduate School of Medicine, Abeno, Osaka 545-8585, Japan | Department of Food and Health Science, Graduate School
of Medicine and Dentistry, Okayama University, Shikatacho, Okayama, 00-8558,
Japan | Department of Graduate Medical Education and General
Practice, Osaka City University Graduate School of Medicine, Osaka 545-8585,
Japan
Note: [] Address for correspondence: Shigekazu Takemura, Department of
Hepato-Biliary-Pancreatic Surgery, Osaka City University Graduate School of
Medicine, Osaka 545-8585, Japan. Tel.: +81 6 6645 3841; Fax: +81 6 6646 6057;
E-mail: takemura@med.osaka-cu.ac.jp
Abstract: A large number of studies have reported the action of
K_{ATP} channel openers in accelerating the proliferation of
hepatocytes and many other cell types in vitro. Few studies, however, have
examined the proliferative effect of K_{ATP} channel openers
in vivo. The aim of this study was to determine whether the
K_{ATP} channel opener minoxidil accelerates liver
regeneration after partial hepatectomy (PH) in vivo. Male Wistar rats
underwent a 70% partial hepatectomy (PH) after receiving a subcutaneous
injection of minoxidil (0.01 mg/kg or 0.03 mg/kg). Some of the rats were
intravenously treated with 5-hydroxydecanoic acid (5-HD, 10 mg/kg) just before
the minoxidil injection. Seventy-two hours after PH, DNA synthesis was
immunohistochemically assessed by bromodeoxyuridine (BrdU) incorporation into
the nuclei. Minoxidil induced significant and dose-dependent increase in the
BrdU labeling index after PH, and 5-HD reversed this minoxidil-induced change.
Minoxidil did not significantly affect the changes in liver weight and liver
function after PH. The hepatic levels of prealbumin decreased by about 60%
after PH and minoxidil inhibited the decrease. In conclusion, the
K_{ATP} channel opener minoxidil enhanced DNA synthesis
after PH without affecting the liver function.
