| A variety of experiments were conducted that explored the characteristics and consequences of sucrose-enhanced diets in rats. These experiments demonstrated that rats consumed about 150 to 200 ml of 10% sugar solution for extended periods of time and incurred several physiological alterations. Rats given continuous, but not intermittent, access to sucrose showed marked differences in organ and body weight which was strongly associated with the daily sucrose intake values. No changes in the densities of neuronal or filial cell populations within select limbic and diencephalic structures were detected after long-term sucrose drinking. However, the sudden removal of sucrose from rats produced increased agonistic-like behaviours that resembled those of addicted humans. Female, but not male rats injected with lithium (3 mEq/kg) and pilocarpine (30 mg/kg) following 3 weeks of 10% sucrose consumption showed faster seizure onset times than animals receiving only water. The effect was moderately correlated with volume of sugar solution consumed per day. Additional experiments showed that neither housing density, nor options for wheel running, nor the addition of multiple bottles of sucrose influenced daily volumes of sucrose consumption. However, relatively high dosages of beta-estradiol (≥0.5 mg/kg) injected subcutaneously once every 4 days to simulate the oestrus cycle, produced significant, but transient depression in sucrose intake in female rats. Finally, it was determined that both natural and artificial geomagnetic-like fields could enhance sucrose drinking in rats. |
