摘要：It has been known for years that free access to sugar solutions can cause weight gain and/or obesity in rats. We recently reported that brief access to sugar solutions can affect the hypothalamic neuropeptides that help to regulate energy balance. In this paper, we present the results in which we examined the effects of these sugars on the expression of several neuropeptides within specific hypothalamic regions. We provided Sprague Dawley rats 24 h access to 15% solutions of glucose, fructose, sucrose or high fructose corn syrup (HFCS) and then dissected portions of the paraventricular hypothalamic nuclei (PVN), the ventromedial hypothalamus (VMH) and the lateral hypothalamus (LH). We then evaluated the expression of several neuropeptides in these tissues, all of which were previously shown to be influenced by free access to sugar solutions using PCR array. Of the four sugar solutions tested, only fructose decreased expression of cholecystokinin (CCK) significantly, and only in the PVN. Glucose and sucrose significantly increased the expression of Tumor Necrosis Factor α (TNF-α) only in the PVN. Fructose and sucrose decreased Growth Hormone (GH) in the VMH. Further analysis indicated that it was fructose intake that was negatively correlated with both CCK and GH expression. Rats that had access to sugar solutions consumed less chow but maintained control levels of total caloric intake. We conclude that 24 h free access to different sugars can influence the expression of several hypothalamic neuropeptides in different ways. Changes in the expression of these neuropeptides do not disrupt total daily energy intake immediately but may nevertheless contribute to the obesity caused by long term access to sugar solutions.
关键词：fructose; HFCS; glucose; sucrose; energy regulation
