Daikenchuto raises plasma levels of motilin in cancer patients with morphine-induced constipation

Abstract

Daikenchuto, a Japanese herbal medicine, has been used to treat the gastrointestinal disorder, and it has been recently suggested that one of the mechanisms for the empirical effect of daikenchuto involves humoral changes in the gastrointestinal peptides. We examined daikenchuto's effect on the symptoms of gastrointestinal obstructions and the plasma levels of various gastrointestinal peptides [motilin, calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP), somatostatin, and substance P] in seven patients having obstructions of morphine-induced gastrointestinal motility (constipation). Blood samples were taken before, and on 1, 3, and 7, day after administration, followed by the extracting procedure, and submitted to a highly sensitive enzyme immunoassay system for gastrointestinal peptide-like immunoreactive substances (IS). A clinical efficacy of daikenchuto was achieved in 4 of the 7 patients. Plasma motilin-IS levels in the responder group significantly increased on day 7 after oral administration of daikenchuto compared with the nonresponder group and were closer to the levels of normal subjects. These results suggest that the pharmacological effects of daikenchuto in improvement of morphine-induced constipation are closely related to changes in plasma motilin-IS levels.