2006 Volume 42 Issue 4 Pages 117-130
An alternative model for the measurement of ureteral peristalsis is described using the goat ureter. Ureters from freshly slaughtered goats (Capra aegagous hircus) were collected from a local slaughter house. The peristaltic reflex of these preparations was recorded using a specially designed apparatus. The preparations were mounted so that contractile responses to drugs could be recorded isometrically. Histological studies were undertaken to enable a correlation to be made between the anatomical observations and the functional studies. The spontaneous peristaltic reflex of the goat ureter (7 ± 2 per 2 min) showed a 50% increase in the frequency of contraction (13.66 ± 1.6, P<0.001) after application of histamine at a concentration of between 6.512 μM and 13.024 μM, but was blocked completely by 10.4 μM of pheniramine (P>0.05). The reflex was not blocked by the H2 blocker ranitidine (P<0.001). The effects of acetylcholine were variable. Calcium chloride at 6.8 μM resulted in a tetanic response (P<0.001). Nicorandil showed partial inhibition of spontaneous peristaltic reflex at 189.4 μM and complete inhibition at 473.4 μM (P<0.001). Although acetylcholine did not show any appreciable effect on the isometric contractions at a maximum dose of 275.2 μM, adrenaline increased the frequency of contractions by 8.2 ± 6.5 (P<0.001), while salbutamol and isoprenaline had no effect. The histology revealed a striking resemblance to the human ureter, with a structure that explained the responses obtained. The anatomic, physiologic and histological similarities to the human ureter make it an effective alternative in tropical countries for research on ureteral peristalsis.