Human and experimental studies of the changes of exocrine pancreatic tissue in hemorrhagic shock

Exocrine pancreatic tissues from 36 human autopsy cases of hemorrhagic shock and from experimental shock rats with 50% blood loss by cardiac puncture were studied by light and electron microscopic techniques. For rule out the possibility of the autolysis, experimental autolytic changes of pancreas were also investigated. 1) In the autopsy cases, the most common case of a fatal hemorrhage was from rupture of aneurysm (66%). By light microscopy, all cases showed acinar anisocytosis and 21 cases (65.7%) showed some localized atrophic areas of acinar cells. But it was difficult to confirm any difference of interstitial changes between shock cases and controls. By electron microscopy, marked dilatation and possible confluence of rough endoplasmic reticulums were observed associated with decrease of mitochondriae and zymogen granules in the above described atrophic areas. 2) In experimental cases, blood pressure soon fell to 30 mmHg after blood loss, then recovered gradually. The pancreatic tissues of the rats were resected in 0.5, 1, 2, 4, 16 and 24 hours after 50% blood loss. By light microscopy, atrophy of acinar cells was observed in teleinsular areas at 0.5 to 16 hours after blood loss. But similar to the autopsy cases, there was not particular difference in interstitial changes between the shock cases and controls. By electron microscopy, swollen mitochondriae (0.5-4 hours cases), dilatation of rough endoplasmic reticulums (2-24 h), lysosomal change containing degenerated mitochondriae, rough endoplasmic reticulums and zymogen granules (1-16 h) and the release of lysosomal degeneration products (0.5-24 h) were observed. 3) Finally above changes were confirmed to be not related with postmortem autolysis and it is concluded that these may represent the cardinal pathological changes induced by hemorrhagic shock per se.