Comparative study of alcohol metabolism in stroke-prone spontaneously hypertensive rats and Wistar-Kyoto rats fed normal or low levels of dietary protein.

Our previous experiments have shown that the appetite or preference for alcohol is affected by the rat strain and nutritional status, such as dietary protein levels. To determine the affected factors in alcohol preference, the alcohol metabolism in SHRSP (stroke-prone spontaneously hypertensive rats) and WKY (Wistar-Kyoto) rats fed with the standard level (15%) or low level (5%) purified egg protein diet (PEP) was investigated. The animals were kept on the experimental diets for 4 weeks. After 12 h fasting, a 15% ethanol solution was given in a dose of 100 mg ethanol per 100 g body weight with a gastric probe to all animals and the blood ethanol and acetaldehyde levels were determined. Compared with 15% PEP diet-fed SHRSP, WKY showed higher levels of blood ethanol and acetaldehyde. Furthermore, the same results were also observed in SHRSP and WKY fed with 5% PEP diet. On the other hand, regardless of the rat strain, rats fed a low level protein diet showed higher blood ethanol and acetaldehyde levels. We also found that there was no significant change in alcohol dehydrogenase (ADH) activity and acetaldehyde dehydrogenase (ALDH) activity between SHRSP and WKY. However, both SHRSP and WKY fed a 15% PEP diet showed higher ADH and ALDH activity compared with rats fed the 5% PEP diet. These results suggested that the affected factors of preference for alcohol may be correlated with blood ethanol and acetaldehyde levels after alcohol intake.