Motility of the ureter of the spontaneously hypertensive rat.

ABSTRACT

BACKGROUND: The spontaneously hypertensive rat (SHR) is a commonly used animal model of hypertension and transplantation studies provide evidence for a renal element to the aetiology of the hypertensive process. AIMS: This study was designed to test the hypothesis that the contractile function of the ureter of the SHR differs to that of the normotensive control Wistar-Kyoto (WKY) rat. METHODS: Ureter segments from SHR (n = 16) and WKY (n = 16) were cannulated and pressurised in vitro. Acetylcholine (ACh) was used to stimulate phasic contractile pressure responses. RESULTS: SHR ureter contractile frequencies were significantly greater than those of WKY (6.6 ± 0.8 vs. 3.8 ± 0.2 min(-1) in 10(-5) M ACh; p < 0.01). Magnitudes of contractile responses were not significantly different (SHR 14.3 ± 1.5 mmHg, WKY 15.2 ± 2.1 mmHg). CONCLUSIONS: SHR ureteral contractile function differs significantly to that of normotensive WKY. Ureteral dysfunction may be a contributory causative factor in the aetiology of the hypertensive disease process.