1) In untreated 5 cases (A), the total number of mast cells was 15275 (average: 3055) in mesentery and 7916 (average: 1583.2) in greater omentum.
On the other hand, the number of atypical mast cells was 1125 (average: 225) in mesentery and 568 (average: 113.6) in greater omentum. The destruction ratio was 7% in both tissues. 2) The control group (B), in which 0.9% saline solution was injected, showed no definite change in the total number and destruction ratio. 3) In the group injecting cancer extract (C), the total number of mast cells in mesentery and omentum decreased and the destruction ratio increased in two tissues. 4) In the group injecting heparin alone (D), the number of mast cells increased remarkably compared to the former group (C), but the destroyed cells did not increase. 5) The next group (E) which was administered with histamine alone, showel the remarkable increase of mast cells and moderate increase in the destruction ratio. 6) The increase of mast cells by administration of heparin was mild in cases of cancer extract injection. In this group, however, the increase of destroyed cells was demonstrated moderately in mesentery and highly in omentum. 7) When the administration of histamine was added to cancer extract injection, the number of mast cells increased to some degree in comparison to the group (C) injected with cancer extract alone.
However, companing to the control group (B) mast cells in mesentery showed no definite increase, while those in greater omentum showed a relationaly marked increase. The destruction ratio increased markedly in former tissue and moderately in latter tissue. 8) The administration of ACTH (adrenocorticotropin) aggravated the decrease of mast cells by cancer extract injection and the destroyed cells increased remarkably in each of two tissues. 9) When ACTH was administrated after heparinization in cases pretreated by cancer extract, the number of mast cells in mesentery and omentum decreased slightly. The destruction ratio increased markedly in the former and slightly in the latter. 10) When the administration of nitromin was added to the cancer extract injection, the cumulative effect of both caused the most profound decrease of mast cells and the most distinct destruction ratio in mesentery and omentum through whole experimental groups.