title: Goat ureter - an alternative model for measuring ureteral peristalsis.
abstract: 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 microM and 13.024 microM, but was blocked completely by 10.4 microM 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 microM resulted in a tetanic response (P<0.001). Nicorandil showed partial inhibition of spontaneous peristaltic reflex at 189.4 microM and complete inhibition at 473.4 microM (P<0.001). Although acetylcholine did not show any appreciable effect on the isometric contractions at a maximum dose of 275.2 microM, 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.
authors.affiliation: Department of Pharmacology, Mahatma Gandhi Institute of Medical Science, Sewagram, India. drsmitakarpate@gmail.com
authors.forename: Karpate
authors.initials: K
authors.lastname: Smita
authors.forename: Verma
authors.initials: V
authors.lastname: Sushil Kumar
authors.forename: John
authors.initials: J
authors.lastname: Premendran
authors.forename: Mohan Lal
authors.initials: ML
authors.lastname: Sharma
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001341:Autonomic Nervous System / Q000502:physiology; D002122:Calcium Chloride / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D006041:Goats; D006632:Histamine / Q000494:pharmacology; D007537:Isometric Contraction / Q000187:drug effects / Q000502:physiology; D023421:Models, Animal; D020108:Nicorandil / Q000494:pharmacology; D010528:Peristalsis / Q000187:drug effects / Q000502:physiology*; D014513:Ureter / Q000166:cytology / Q000294:innervation / Q000502:physiology*
chemical_list: D020108:Nicorandil; D006632:Histamine; D002122:Calcium Chloride; D000109:Acetylcholine; D004837:Epinephrine