FUTURE-DIRECTIONS FOR REDUCTIONISTIC RESEARCH IN GASTRIC-SECRETION AND DEFENSE

Our theme centers on the complex processes that constitute and regulat e the function of the gastric mucosa. Although some investigators prom ote the critical importance of a given element, such as acid, blood fl ow, or mucus, it is clear that both gastric secretory function and muc osal defense and repair mechanisms are multifactorial and are regulate d by redundant control circuits. While it is true that critical studie s can be performed in vivo with intact mucosa, at the same time it is frequently difficult, using these methods, to define the specific cell ular elements involved in the regulation of secretion, defense, and re pair. We now recognize that ulcer disease does not occur simply when t his balance is thrown off. To the contrary, ulcer disease commonly occ urs when the normal mucosal mechanisms are perturbed by Helicobacter p ylori-associated gastro-duodenitis or nonsteroidal anti-inflammatory d rugs. In the absence of such perturbation, the redundancy of the regul atory mechanisms underlying gastric secretion and the multiple lines o f defense and healing would render ulcer disease rare indeed.