Hung C R, Cheng J T
Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China.
Chin J Physiol. 1994;37(4):213-8.
The effects of cimetidine and NaHCO3 on gastric acid back-diffusion (either the H+ loss or the Na+, K+ and CA++ gain in the gastric lumen) and mucosal ulceration were studied in rats with chronic feeding of betel quid chewing (BQC)- or its individual component-containing food. After 30 and 90 days of feeding, the animal was fasted for 24 hrs and vagotomized. An acid solution (100 mM HCl plus 54 mM NaCl) with or without drugs was irrigated in the rat stomach for 3 hrs. The results indicated that BQC and its individual component produced a variety of change in enhancement in acid solution-induced acid back-diffusion and mucosal hemorrhagic ulceration but in decrease of gastric mucus secretion. These parameters were dose-dependently reversed by intragastric cimetidine (50-300 mg/kg) in BQC-treated rats. Similar but lesser effect than cimetidine (300 mg/kg) was obtained by intragastric administration of NaHCO3 (52 mg/kg). It is concluded that in BQC- or its component-feeding rats, the enhancement in acid back-diffusion and the reduction in mucus secretion are at least in part responsible for the formation of hemorrhagic ulceration which can be inhibited by intragastric cimetidine or NaHCO3.
在长期喂食含槟榔咀嚼物(BQC)或其单一成分食物的大鼠中,研究了西咪替丁和碳酸氢钠对胃酸反向弥散(即胃腔内氢离子丢失或钠离子、钾离子和钙离子增加)及黏膜溃疡形成的影响。在喂食30天和90天后,动物禁食24小时并进行迷走神经切断术。将含有或不含有药物的酸性溶液(100 mM盐酸加54 mM氯化钠)灌入大鼠胃内3小时。结果表明,BQC及其单一成分在酸性溶液诱导的胃酸反向弥散增强和黏膜出血性溃疡形成方面产生了多种变化,但胃黏液分泌减少。在经BQC处理的大鼠中,胃内给予西咪替丁(50 - 300 mg/kg)可使这些参数呈剂量依赖性逆转。胃内给予碳酸氢钠(52 mg/kg)可获得与西咪替丁(300 mg/kg)相似但较弱的效果。得出的结论是,在喂食BQC或其成分的大鼠中,胃酸反向弥散增强和黏液分泌减少至少部分是导致出血性溃疡形成的原因,而胃内给予西咪替丁或碳酸氢钠可抑制这种情况。