臨牀消化器内科 Vol.12 No.2(2)


特集名 高齢者と消化管
題名 加齢と胃酸分泌能
発刊年月 1997年 02月
著者 屋嘉比 康治 帝京大学医学部第三内科
【 要旨 】 最近まで,胃酸分泌は加齢とともに低下すると一般的には考えられてきた.著者らの検討でもBAOおよびMAOが50歳代以降低下しており,さらに単離壁細胞の実験においても壁細胞の酸分泌活勤が加齢によって低下していることが認められ報告してきた.しかし,H.pylori時代を迎え,萎縮性胃炎の主要な原因としてH.pyloriが取り上げられ,これまで胃粘膜萎縮は加齢に伴う生理的な現象と考えられてきたが,萎縮は長期のH.pylori感染症の結果である可能性が出てきた.また,高齢者でも胃粘膜萎縮のない場合は酸分泌は減少しないことが報告されており,さらに高齢者において酸分泌が増加しているとの報告も認められる.それらの研究において,H.pylori感染が酸分泌減少に関与していることが示されており,加齢による酸分泌機能の低下がH.pylori感染率の増加あるいは長期感染の結果であることが示唆されている.加齢による酸分泌機能の低下が生理的な現象といえるか再検討すべきときである.
Theme GI Tract in the Elderly
Title Aging and Gastric Acid Secretion
Author Koji Yakabi Internal Medicine, Teikyo University Ichihara Hospital
[ Summary ] Until recently, it was generally accepted that gastric acid secretion decreased with advarcing age. In our previous study, BAO and MAO were shown to decrease with age after the sixth decade. In vitro studies using isolated parietal cells have also shown the acid secretion response of parietal cells to decrease with age. After the flood of studies on H.pylori, however, H.pylori infection was assumed to be the main canse of atrophic gastritis. The view that gastric mucosal atrophy might be the result of long-term H.pylori infection replaced the concept that atrophy was dependent on physiologic change occurring with age. There have now been studies which showed that gastric acid secretion does not decrease with age. A recent study found that acid recretion was higher in the elderly than in the young. From these studies, it was suggested that H.pylori infection is related to decreased acid secretion, meaning that this decrease in acid secretion with age results from an increased rate of infection or from long-term infection with H.pylori. The view that the decrease in acid secretion is a physiological phenomenon has to be studied reconsidered the era of H.pylori investigation.
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