Influence of nitric oxide-mediated vasodilation on the blood pressure measured with the tail-cuff method in the rat

Abstract

Systolic blood pressure (SBP) is frequently measured in rats by the tail cuff method, which usually comprises pulse/flow disappearance and reappearance during cuff inflation (Inf) and deflation (Def), separated by an interval between cycles (IBC). Although Def values are habitually used to estimate SBP, in 58 Wistar rats we found (Def-Inf) to be -6 +/- 1 mmHg, indicating that Def < Inf in most cases. When the IBC was lengthened to 2 min, (Def-Inf) was increased to -17 +/- 2 mmHg, indicating the probable accumulation of a vasodilating metabolite. This increase of (Def-Inf) was prevented by papaverine, indicating its relation to smooth muscle contractility. Adrenergic blockade did not prevent the increase of (Def-Inf), but pretreatment with L-NAME decreased it to -5 +/- 2 mmHg (p < 0.05). Simultaneous measurement of SBP by tail-cuff method and carotid cannulation revealed that the Inf value was the most accurate estimation of intravascular SBP. We conclude that: (1) the Inf value should be taken as representative of SBP, since depending on the duration of suprasystolic compression the Def value can underestimate it, and (2) nitric oxide accumulation due to flow deprivation was the main cause of SBP underestimation by Def values.

Overweight during lactation and its implications for biometric, nutritional and cardiovascular parameters of young and adult male and female rats

“…Haemodynamic evaluation was performed by indirect measurement of systolic blood pressure and heart rate through the tail-cuff method ( 22 , 23 ) . The assays occurred in the morning after 3 d of acclimatisation using the ADInstruments ML125 NIBP (Non-Invasive Blood Pressure) system connected to the ADInstruments PowerLab/400 digital–analogue converter.…”

Diminished expression of dihydropteridine reductase is a potent biomarker for hypertensive vessels

“…The animals were maintained at a constant temperature of 21±2°C and 55±8% relative humidity on a normal 12–12 h light–dark cycle. The SBP of SHR and WKY rats at 5, 8 and 13 wk of age was measured indirectly using the tail‐cuff method in conscious rats, as described previously 16. Blood pressure was measured six times, and the average was used for individual data.…”

Amaranth seed protein hydrolysates have in vivo and in vitro antihypertensive activity

“…Rats were placed in a chamber at 37°C for 10 min, and then transferred to a standard setup (2008; Fritz & Rinaldi, 2007) with heating pad and acrylic restrainer, tail cuff and pulse sensor (Narco Biosystems, Houston, TX). The tail cuff was connected to a cylinder of compressed air through an arrangement of inlet and outlet valves that permitted inflation and deflation of the cuff at a constant rate.…”