Jacobs D M, Sturtevant R P
Anat Rec. 1982 May;203(1):101-13. doi: 10.1002/ar.1092030110.
The ultrastructure of rat gastric parietal cells was studied at six timepoints of the 24-hour day. The rats, maintained on a 12 hour:12 hour light-dark regimen, had been subjected to either a 40-hour fast or to a 4-hour mid-light restricted feeding period. At each time point, the volume density (Vv) of secretory canaliculi, surface density (Sv) of microvesicles and RER, and the numerical density (Nv) of multivesicular bodies were determined in cells of the neck and base of glands. Circadian variation of the four variables was suggested in both experiments. Canalicular and microvesicular measurements suggested that a rhythm in gastric acid secretion may persist during fasting; a peak and trough, respectively, occurred in the late dark phase, as in our previous report on ad libitum-fed rats. Restriction of feeding to that which is normally the rat's resting phase caused an apparent 180 degree phase-shift in the rhythm. The data suggested, however, that additional factors may have influenced the cellular activity pattern. At all timepoints in both experiments cells of the neck of glands had higher RER and canalicular values than did cells of the base of glands. This suggests that parietal cells in glandular necks may be more active than those farther removed from the stomach lumen. There was no correlation between the Nv of multivesicular bodies and glandular location of the cells.
在一天24小时中的六个时间点对大鼠胃壁细胞的超微结构进行了研究。这些大鼠维持12小时光照：12小时黑暗的作息制度，分别经历了40小时禁食或4小时的光照中期限时喂食期。在每个时间点，确定腺体颈部和底部细胞中分泌小管的体积密度（Vv）、微泡和粗面内质网的表面密度（Sv）以及多囊泡体的数量密度（Nv）。两个实验均提示这四个变量存在昼夜节律变化。对分泌小管和微泡的测量表明，禁食期间胃酸分泌的节律可能持续存在；如我们之前关于随意进食大鼠的报告所述，分别在黑暗后期出现高峰和低谷。将喂食限制在通常是大鼠休息阶段的时间，导致节律出现明显的180度相移。然而，数据表明可能有其他因素影响了细胞活动模式。在两个实验的所有时间点，腺体颈部细胞的粗面内质网和分泌小管值均高于腺体底部细胞。这表明腺颈部的壁细胞可能比离胃腔较远的壁细胞更活跃。多囊泡体的数量密度与细胞的腺体位置之间没有相关性。
