Figure 7.

Effects of chronic oxaliplatin treatment on serotonin levels in the stomach. (A) Representative amperometric traces of the current generated by serotonin (5-hydroxy tryptamine (5-HT)) oxidation at the mucosal surface of the stomach. The current (nA) was converted to 5-HT (µM) by calibrating carbon fibre electrodes with a 10 µM 5-HT solution, as depicted in vertical scales. Mechanical stimulation of the gastric mucosa produced a compression-evoked release (peak) of 5-HT, which decayed back to basal levels (steady state) in both sham (grey traces) and oxal-treated mice (black traces). The dotted lines represent the baseline. (B) Group data comparing ‘peak’ and ‘steady state’ 5-HT levels between sham and oxal-treated mice. (C) ECL cells visualised by fluorescent immunohistochemical detection of 5-HT (red) in the mucosa of the gastric body (scale bar = 50 µm). (D) Quantification of ECL cells (5-HT + ve) in the gastric body of sham- and oxal-treated mice normalised per number of gastric pits. Data are presented as the mean ± SEM. The number of animals is shown in parentheses. ** p < 0.01.