Stress ulcers is a trouble complication of subarachnoid hemorrhage (SAH). Although gastrointestinal ulcerations may be attributed to increased HCL secretion in SAH; the exact mechanism of that complication has not been investigated definitively. We studied if vagal network degeneration may cause intestinal atrophy following SAH. Study was conducted on 25 rabbits, with 5 control group (Group-A), 5 SHAM group (Group-B), and 15 SAH group via injection of autologue blood to cisterna magna. Seven animals followed for seven days (Early Decapitated-Group-C) and eight animals followed 21 days (Late Decapitated-Group-D). The vagal nodosal ganglia (NGs), Auerbach plexuses and goblet cells of duodenums were examined by current stereological methods and compared statistically. The mean numbers of degenerated axon density/mm(2) of gastric branches of vagal nerves was 8 +/- 2, 34 +/- 11, 189 +/- 49 and 322 +/- 81 in the Group A, B, C, and D respectively. The mean numbers of degenerated neuron density/mm(3) of NGs was 5 +/- 2, 54 +/- 7, 691 +/- 87 and 2930 +/- 410 in the Group A, B, C, and D respectively. The mean numbers of degenerated Auerbach neurons 2 +/- 1, 4 +/- 1, 12 +/- 3 and 27 +/- 5/mm(3) in the Group A, B, C, and D respectively. The mean numbers of degenerated goblet cells/mm(3) were 4.3 +/- 1.02, 11.5 +/- 0.26, 143 +/- 26 and 937 +/- 65 Group A, B, C, and D respectively. Statistical analysis showed that vagal network ischemia could cause intestinal bleeding and so atrophy in SAH progression. Statistical analyses of groups were; Group-D/Group-A < 0.001, Group-D/Group-B < 0.005, Group-C/Group-A < 0.005. Undiscovered effect of ischemic vagal network injuries should be regarded as a major cause of stress ulcerations following SAH which has not been mentioned in the literature. (C) 2018 Elsevier Ltd. All rights reserved.