ガストリン分泌能・ガストリン細胞分布よりみた慢性胃炎と腺境界

Clinicopathological Study of G-cell Area and Antral Gastritis

要旨　広範胃切除術を受けた44例(十二指腸潰瘍16例，胃潰瘍8例，胃癌20例)について，術前に胃酸分泌能，ガストリン分泌能を測定し，切除胃のガストリン細胞(G細胞)を酵素抗体法にて同定，G細胞総数，G細胞領域，慢性胃炎の程度を検索し，これらをまとめて検討した．ガストリン分泌能はG細胞総数と相関した．幽門腺萎縮，腸上皮化生は共にその程度が進行するにつれて，G細胞総数の減少をもたらし，同時にガストリン分泌能の低下をもたらすことが判明した．すなわち形態学的に認められる幽門腺領域の慢性胃炎の進行に伴い，同領域の機能としてのガストリン分泌能の低下の起こることが判明した．胃酸分泌能とガストリン分泌能との間には相関関係がなく，胃底腺領域と幽門腺領域の慢性胃炎の進行が無関係に起こることが示唆された．G細胞領域は幽門腺，偽幽門腺の分布と完全に一致する症例がなく，中村のF境界線とも一致しなかった．中村の通常型に当たる38例では，G細胞領域の面積は年齢，幽門腺萎縮，腸上皮化生の程度との間に相関関係を認めず，偽幽門腺の拡がりとも無関係であった．すなわち加齢に伴い偽幽門腺が噴門側に拡がっても，G細胞領域は拡がらないことが判明した．

　To determine the effect of varying degrees of chronic gastritis on the gastric secretion, five factors were analyzed in 44 patients (duodenal ulcer 16, gastric ulcer 8, gastric cancer 20); gastric acid output, postprandial gastrin response (percent peak gastrin responce, %PGR), degree of pyloric gland atrophy and intestinal metaplasia in the pyloric antrum, and total G-cell number (TGCN). G-cells were studied by the specific immunoperoxidase method. There was a significant positive correlation between TGCN and %PGR. TGCN was inversely related to degree of pyloric gland atrophy and intestinal metaplasia. There was a fall in postprandial gastrin response with increasing grade of pyloric gland atrophy and intestinal metaplasia. It is concluded that chronic gastritis causes a reduction in gastrin secretion associated with a decrease in G-cell population. No correlation was found between gastric acid output and postprandial gastrin response.

　G-cell distribution (G-cell area) was also studied. The size of G-cell area was estimated in 38 cases without extremely diffuse intestinal metaplasia, and it was not related toage, and degree of pyloric gland atrophy and intestinal metaplasia. There was no case with the proximal border of pseudopyloric gland distribution corresponding completely with that of G-cell area. Nakamura's F boundary line was not associated with G-cell area. It issuggested that G-cell area remains unchanged, although distribution of pseudopyloric gland and intestinal metaplasia extends with advancing age.