title: A murine model for multiple laparoscopies: I. Early lymphoid response to intraperitoneal insufflation of CO2.
abstract: In a model for multiple laparoscopies proliferation of T-lymphocytes was an early, but transitory, immunologic reaction in the spleen to intraperitoneal CO2 insufflation. Intraperitoneal insufflations of approximately 3.5 ml of CO2 were given daily to three groups of BALB/c mice for 11, 20, and 32 consecutive days, respectively. Air insufflation was given to experimental controls. The observations in the insufflation model are summarized as follows: 1) Multiple CO2 insufflation approximately doubled the number of splenic T lymphocytes. 2) The percentage value was highest on the day of the last insufflation. The difference between this value in each of the three groups was statistically not significant; ie, there was no dose-response relationship in the range of 11-32 insufflations. 3) There was a dose-response effect in the range of 3-9 insufflations. 4) The number of splenic T lymphocytes decreased with each day after the end of treatment. Untreated control values were reached in 12-16 days. 5) Air insufflation had only a minimal effect on the proliferation of T lymphocytes in the spleen. In this model there is correlation between early proliferation of T lymphocytes in the spleen and the late occurrence of a high incidence of malignant lymphoma (approximately 60%). The long-term survivors of CO2 insufflation also developed a wide spectrum of intraabdominal malignancies. It was speculated that CO2 insufflation provided an abnormal internal environment that affected a variety of target tissues. Prolonged CO2 accumulation might have modified nucleic acid structure via chronic intracellular acidosis. Could the neoplastic sequelae in this model be a clue to a similar sequel in humans after multiple laparoscopies?
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000633:toxicity*; D005260:Female; D006965:Hyperplasia; D010535:Laparoscopy / Q000009:adverse effects*; D008198:Lymph Nodes / Q000473:pathology; D008214:Lymphocytes / Q000187:drug effects*; D008223:Lymphoma / Q000209:etiology; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000473:pathology
chemical_list: D002245:Carbon Dioxide