Some effects of hypophysectomy on gastrointestinal function and structure

The dependence of gastric mucosal structure and function on hormonal activity has been the subject of many investigations (Welbourn and Ward, 1962; Zollinger and Craig, 1960; Grossman, 1950). The conflicting nature of experimental findings and interpretations, particularly as related to the effect of adrenal cortical hormones on gastric secretion, is reflected in many articles reviewing this subject (Bachrach, 1963; Sulman and Kirsner, 1963; Smith, Delamore and Williams, 1961; Clarke, Neill, and Welbourn, 1960; Wiederanders, Classen, Gobbel, and Doyle, 1960; Gray, 1957; Kirsner, 1957). Similarly, there is contradiction among reports dealing with the relationship between hormonal activity and small intestinal absorption (Adlersberg, Colcher, and Drachman, 1951), although the literature contains fewer papers on this subject. At best it can be stated that there are more articles presenting evidence that adrenal cortical hormones increase gastric secretion and accelerate intestinal absorption than there are denying this contention. Hypophysectomy has been reported to decrease gastric secretion (Abrams and Baker, 1954; Enriquez de Salamanca, Garcia-Morato Castafno, LopezPorruia, and Castro-Rial Canosa, 1953; Crafts and Walker, 1947; Cutting, Dodds, Noble, and Williams, 1937). Intestinal absorption of carbohydrate and fat has also been reported to decline following hypophysectomy or adrenalectomy (Russell, 1938; Verzair and McDougall, 1936). Among the mechanisms implicated in these gastrointestinal responses to endocrine ablation are mucosal atrophy (Haeger, Jacobsohn, and Kahlson, 1953), cellular involution (Abrams and Baker, 1954), and the loss of various direct or indirect influences of adrenal cortical hormones (Clarke et al., 1960; Verzar and McDougall, 1936; Baker, 1957; Baker and Clark, 1961; Stempien and Dagradi, 1954) or other hormones (Welbourn and Ward, 1962; Clarke et al., 1960; Abrams and Baker, 1954; Baker and Clark, 1961). The experiments in this paper were designed to assess further some of the mechanisms involved in gastrointestinal responses to hypophysectomy. A series of chronic studies of hypophysectomized dogs are reported.