Orientación de las consecuencias

Blood pressure showed a significant diet*sex interaction and also varied significantly with the time of day, therefore results are presented mainly as graphs with time on the x-axis. For all challenges except the anxiety challenge the telemetered animal had a companion in the cage and group n were as follows: CD, male n=6, female n=6, FD male n=5, female n=5, SD, male n=5, female n=5 and FSD, male n=5, female n=5.

2.5.1 R

A 7-day period was allowed and rats were left alone with cage mates and minimal disturbance in sound-proofed room on a 12h (07.00am-07.00pm) light-dark cycle. During this period blood pressure and heart rate measurements were recorded using Dataquest A.R.T data acquisition system (DSI, St-Pauls MN USA) on a scheduled recording format (30s/15min.). This was done to ensure a reduction in blood pressure from the date of surgery and a levelling out of blood pressure observed. Over the course of seven days a levelling out of blood pressure and heart rate was observed in all animals with clear circadian rhythmicity. This was assumed to be the best representation of basal blood pressure and heart rate post surgery.

2.5.2 B

All animals were allowed to recover for seven days before commencing basal blood pressure recording. Telemetry animals and cage mates were fed standard non-purified chow (AIN- 93G, Harlan Teklad. Maddison WI.) and water ad libitum. Telemetry data acquisition software (DSI) recorded data continuously for 48 hours to measure day and night basal blood pressure variables, heart rate and activity. Rats were recorded at 30sec intervals over this period and data were analysed either by fitting separate fourier curves to all data points (2880 data points per animal per day) within treatment groups, or by compressing the data to hourly means over a representative 24h period.

2.5.3 A

To induce a stress response upon the telemetered animals, an anxiety challenge was devised. Cage mates of all telemetered animals were removed and placed into separate wire mesh and plastic cages for 24 hours. Telemetry data acquisition software (DSI) was set to record data continuously for 24 hours immediately after the telemetered animal and cage mate had been separated, to provide a measureable stress response in the telemetry animals. Rats were recorded at 30s. interval for 24h (starting at ~10.00am) and data analysed as above. Once the 24 hours had elapsed, all telemetered animals were reunited with the same cage mate.

2.5.4 N

-

-L-

(L-NAME)

N(G)-nitro-L- arginine methyl ester (L-NAME), is a non-specific inhibitor of nitric oxide synthase and hence, causes vasoconstriction by removing the vasodilator influence of NO and is widely used to induce hypertension in mammals. L-NAME was provided in drinking water at 150 mg L-1(150 µg ml-1). 150mg of L-NAME was weighed and added to a 1L flask of fresh water and made fresh, daily. Once the solution had been mixed adequately the water was poured into small animal drinking bottles ready for feeding. Telemetry animals and cage mates (untelemetered) were fed standard non-purified chow (AIN-93G, Harlan Teklad. Maddison WI.) ad libitum. A seven day feeding regime was decided to be the best experimental approach to ensure a consistent intake of the L-NAME treated water. Adult rats were found to drink on average 27ml day-1 (Section 5.5.1), with no effect of prenatal dietary group. Therefore during the challenge the rats were consuming on average 4.12 mg L-NAME day-1. Telemetry data acquisition software (DSI) was set to record data at scheduled intervals (30s/15min) for 7 days to measure day and night basal blood pressure variables, heart rate and activity. Rats were recorded at 15min intervals for 7 days. Data were analysed either by fitting separate fourier curves to all data points (672 data points per animal [96 per day]) within treatment groups, or by compressing the data to hourly means. All animals were given a 7 day wash out period after L-NAME feeding.

2.5.5 S

Telemetry animals and cage mateswere fed purified control chow with added 4% NaCl (TD.08162 Teklad Harlan, Maddison WI.) and fresh water ad libitum. Telemetry data acquisition software (DSI) was set to record data at scheduled intervals (30s/15min) for 7 days to measure day and night basal blood pressure variables, heart rate and activity. All animals were given a 7 day wash out period after salt feeding. Data were analysed either by fitting separate fourier curves to all data points (672 data points per animal [96 per day]) within treatment groups (Fourier figure), or by compressing the data to hourly means.

2.5.6

A 10% fructose solution was prepared by weighing 50g of fructose and adding to a 500ml of fresh water. Having mixed adequately, the solution was poured into small animal drinking bottles for feeding, fructose solution was prepared fresh, daily. Telemetry animals and cage mates (untelemetered) were fed standard non-purified control chow (AIN-93G, Harlan Teklad. Maddison WI.) and 10% fructose solution ad libitum. Telemetry data acquisition software (DSI) was set to record data at scheduled intervals (30s/15min) for 7 days to measure day and night basal blood pressure variables, heart rate and activity. Data were analysed either by fitting separate fourier curves to all data points (672 data points per animal [96 per day]) within treatment groups, or by compressing the data to hourly means.

2.5.7 V

Telemetry animals were removed from group housed cages and individually housed in activity analysis cages (Lafayette Instruments USA) for 7 days. While housed in the activity cages, animals had unrestricted access to the running wheels and any activity was voluntary. Every 24 hours total activity was measured in wheel revolutions by an electronic counter and recorded. All animals were fed standard non-purified chow (AIN-93G, Harlan Teklad. Maddison WI.) and water ad libitum for the duration of the activity challenge. Telemetry data acquisition software (DSI) was set to record data continuously for 24 hours to measure day and night basal blood pressure variables, heart rate and activity. Data were analysed either by fitting separate fourier curves to all data points (672 data points per animal [96 per day]) within treatment groups (Fourier figure), or by compressing the data to hourly means. On completion of the experiments all animals were euthanized by subjecting the animal to a rising concentration of CO2and cervical dislocation to confirm death. The telemetry implant units (TA11PA-C40) were then dissected from the animals. The implant units were then cleaned and returned to Data Sciences International Ltd. for reconditioning before reuse.