Proceedings of The Physiological Society

University of Oxford (2011) Proc Physiol Soc 23, C7

Oral Communications

Short term statin treatment does not affect blood pressure in 5 week old rats

P. H. Keskivali1, N. P. Curzen1,2, G. F. Clough1, C. Torrens1

1. Vascular Biology Group, Faculty of Medicine, University of Southampton, Southampton, United Kingdom. 2. Wessex Cardiothoracic Unit, University of Southampton, Southampton, United Kingdom.

Statins (HMG Co-A reductase inhibitors) have been proven to be effective in secondary prevention of cardiovascular disease (CVD) with increasing evidence for their effectiveness in primary prevention (Ridker et al., 2008). In rats, maternal protein restriction leads to raised blood pressure and endothelial dysfunction in adult male offspring, which can be improved with long term chronic statin treatment (Torrens et al., 2009). The aim of the current study was to determine if statin treatment over an early two week period had any effect on blood pressure. Female Wistar rats were fed either a control (C, 18 % casein) or protein restricted (PR, 9% casein) diet throughout gestation from conception to term. On delivery dams and pups were returned to standard chow. At 3 weeks of age pups were weaned and further divided into two subgroups of controls and those receiving statin. This gave the four experimental groups; control (C), control + statin (CS), protein restricted (PR) and PR + statin (PRS). At 5 weeks blood pressure was recorded using a non-invasive blood pressure monitor. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured and mean arterial pressure (MAP) was calculated. To minimise variations five stable readings were obtained, the highest and lowest of which were then discarded and the three remaining readings were used to calculate the mean. Results are expressed as mean ± SEM. Differences were assessed by one-way ANOVA. Significance was assumed at p<0.05. Maternal weight gain, litter size and birth weight were similar between the groups. Neither systolic pressure (mmHg: C, 130.5±9.5, n=9; CS, 113.1±6.4, n=9; PR, 121.4±11.8, n=7; PRS, 119.3±6.6, n=7) nor diastolic pressure (mmHg: C, 93.3±9.0, n=9; CS, 78.6±6.0, n=9; PR, 89.3±9.2, n=7; PRS, 85.0±8.6, n=7) were different in male offspring. This was also true in female offspring for both systolic (mmHg: C, 117.2±11.3, n=7; CS, 121.2±9.7, n=8; PR, 126.4±9.7, n=7; PRS, 125.0±9.8, n=8) and diastolic pressure (mmHg: C, 82.8±10.5, n=7; CS, 86.2±8.5, n=8; PR, 91.7±9.7, n=7; PRS, 85.8±4.4, n=8) The current data suggest that the blood pressure rises previously reported in this model are not present at five weeks of age. In addition, they show that even though long-term statin treatment has been shown to have positive effects in this model, they do not appear to be effective after a shorter exposure.

Where applicable, experiments conform with Society ethical requirements