The effects of blood motilin and gastrin on electrical activity and emptying of the intrathoracic stomach after esophagectomy for cancer

Abstract

To observe the effects of blood motilin and gastrin on the electrical activity and emptying of the intrathoracic stomach after esophagectomy for cancer. Electrogastrography and determination of blood motilin and gastrin were carried out in 52 subjects, including 20 normal volunteers and 32 esophageal cancer patients before and 1, 3, 6, 12 months after operation. Gastric emptying of radiopaque granula was studied in 35 of the 52 subjects, including 5 normal volunteers, 7 preoperative patients and 23 postoperative patients. The preoperative gastric emptying of radiopaque granula was 28.0 +/- 8.0 pieces 120 second after eating the test meal, significantly less than that of the normal controls [(38.0 +/- 2.0) pieces, t = 3.515, P = 0.006], and decreased to (16.0 +/- 4.8) pieces one month after esophagectomy (t = 6.987, P = 0.000), and then recovered to 16.8 +/- 4.8 one year after surgery but still could not reach normal (t = 9.387, P = 0.0000). Compared with the normal controls, the amplitude of electrogastrogram (EGG) of the preoperative patients was (229 +/- 118) microv, not significantly different from that of the controls [(226 +/- 62) microv, t = 0.085, P = 0.933], and the frequency of EGG of the preoperative patients was (3.1 +/- 0.2) times per minute, not significantly different from that of the controls too [(3.2 +/- 0.1) times per minute, t = 0.872, P = 0.387]. But the frequency and amplitude of EGG of the patients one month after operation were (2.9 +/- 0.3) times per minute and (172 +/- 46) microv respectively, both significantly decreased in comparison with those of the normal controls (t = 2.336, P = 0.024; and t = 3.118, P = 0.003). The amplitude reached normal [(223 +/- 60) microv, t = 0.145, P = 0.885] 1 year after surgery, but the frequency still remained at a low level [(3.0 +/- 0.1) times per minute, t = 2.208, P = 0.033). The level of blood motilin of the preoperative patients was (488 +/- 197) ng/L, significantly higher than that of the controls [(248 +/- 98) ng/L, t = 5.030, P = 0.000], and the blood gastrin level of the preoperative patients was (26 +/- 15) ng/L, significantly higher than that of the controls [(20 +/- 12) ng/L, t = 2.741, P = 0.043]. One year after operation the blood motilin level maintained at a high level [(443 +/- 129) ng/L, t = 3.725, P = 0.001], and the gastrin level remained at a high level too [(48 +/- 23) ng/L, t = 3.703, P = 0.001]. Physiologically important, persistent elevation of blood gastrin and motilin in the patients who underwent esophagectomy for cancer facilitates the recovery of electrical activity and emptying of the intrathoracic stomach.