Alteration of salivary amylase concentration in submandibular gland (SMG) of Wistar rats by the effect of Bevacizumab, 5-Fluorouracil and Oxaliplatin.

Objectives: Bevacizumab, 5-Fluorouracil and Oxaliplatin inhibit neovascularization and tumor proliferation. Reports on these combined therapeutic schemes and their effect in salivary glands are scarce. A marker of functional activity in GSM was evaluated experimentally by determining the concentration of salivary amylase.
Methods: Forty-eight three-month-old male Wistar rats with body weight (bw) 300/350 grams were used divided into: G1 (control, n: 8), G2 (5-fluorouracil+Leucovorin Calcium, n:8), G3 (Bevacizumab, n:8), G 4 (Oxaliplatin, n:8), G5 (5-Fluorouracil+Leucovorin Calcium+ Bevacizumab+Oxaliplatin, n:8), G6 (paired feeding, no drug, n:8). They received ad libitum feeding, except G6. Doses applied intraperitoneally: G2 (20mg and 10 mg/kg bw for 5 consecutive days), G3(10 mg/kg bw on days 1 and 15), G4 (8 mg/kg bw on days 1 and 15) and G5 (drugs of G2, G3 and G4 were administered). The animals were fasted, anesthetized, GSM were removed and sacrificed. Salivary amylase concentration was measured by spectrophotometric method. Comparison between groups was performed by Analysis of Variance, setting p value > 0.05 for statistical significance. Protocol approved CICUAL: FCM - FO - UNC.
Results: The means were:137.9 ± 4.64, 60.95±4.64, 120.93 ± 4.96, 26.17 ±4.64, 10.77 ±4.64 and 82.87 ±4.64 U/gram of gland for G1, G2, G3, G4, G5 and G6. G1 showed a significantly higher salivary amylase concentration relative to the other groups (p>0.0001). G4, G5 and G1,G3 had the lowest and highest amylase concentration respectively .
Conclusions: The combined administration of cytostatics and monoclonal antibodies would alter the functional activity of GSM due to the deleterious action of cytostatic drugs, not due to Bevacizumab. Further study on parotid gland will be carried out.