In vitro evaluation of the contractile response to endothelin-1 of the circular and longitudinal myometrial layers of the uterine horn of nongravid mares.

Objective: To characterize the in vitro response of circular and longitudinal myometrial layers of the uterine horn (CMLH and LMLH, respectively) of horses to endothelin (ET)-1 by use of specific ETA (BQ-123) and ETB (IRL-1038) receptor antagonists.

Sample Population: Uteruses from 10 nongravid mares in anestrus.

Procedure: Muscle strips from the CMLH and LMLH were suspended in tissue baths and connected to force-displacement transducers interfaced with a polygraph.

Laparoscopic repair of ruptured urinary bladder in a stallion.

A 12-year-old stallion was evaluated because of pollakiuria; endoscopy of the urinary tract during general anesthesia revealed that the urinary bladder was intact. After recovery, the stallion developed clinical and biochemical signs of bladder rupture, which was confirmed by endoscopy. Cystoplasty in adult stallions represents a unique surgical dilemma; the large distance between the incision site and the bladder necessitates the repair be accomplished under maximum tension with minimal exposure.