Shigeki Koyama

Effects of pentagastrin and carbachol on the gastric histamine level in α-fluoromethylhistidine-treated mice and rats

SummaryThe gastric mucosal histamine level in mice increased by about 80% and 100% after fasting for 24 and 48 h, respectively. In non-fasted mice, α-fluoromethylhistidine (α-FMH), a specific histidine decarboxylase inhibitor, significantly decreased the histamine level, the reduction amounting to 35% and 49%, 2 h and 4 h after treatment, respectively. In mice fasted for 24 h, a significant decrease of 42% was observed 4 h after treatment. However, in mice fasted for 48 h, no significant decrease was seen even 4 h after α-FMH treatment. Therefore, the histamine-releasing effect of re-feeding and drugs on the gastric mucosa was examined in vivo, using animals fasted for 48 h and subsequently treated with α-FMH. Food given simultaneously with α-FMH to 48-h fasted mice significantly decreased the histamine level 4 h later. Pentagastrin and carbachol administered alone (0.25–2.0 mg/kg, i.p.) had no significant effect on the histamine level. However, the combined treatment with these drugs significantly decreased the histamine level. In rats fasted for 48 h and treated with α-FMH, pentagastrin (0.25 and 0.5 mg/kg, i.p.) but not carbachol (0.125 – 0.5 mg/kg, i. p.) caused a significant decrease in the mucosal histamine level. In contrast to mice, the effect of the combined treatment with pentagastrin and carbachol was not synergistic in rats. These findings suggest that gastrin acts synergistically with acetylcholine in the histamine release from the gastric mucosa in mice, whereas such synergism may not occur in rats.

Pediatric acute lymphocytic leukemia with osseous changes in jaws: Literature review and report of a case

A case of acute lymphocytic leukemia (ALL) in a child is presented. We also reviewed the recent literature of similar cases describing leukemic jaw bones involvement in Japan. Radiographic examinations of the patient disclosed diffuse osteolytic changes of the entire jaws, the corticated border of the crypts of developing teeth, loss of lamina dura, a thickened periodontal space and disappearance of the radiopaque lines that delineate the borders of the mandibular canal. Pronounced regression and restoration of the alveolar bone and the crypts were detectable on the radiographs taken after a course of the treatment for ALL.An apparent radiographic change of jaw bone after the treatment indicates that the radiographic examinations of children with leukemia in the leukemic process are of quite diagnostic value.