Robert F. Derr

Pain perception in decapitated rat brain

The question of humaneness of decapitation per se has been considered. The time required for the oxygen tension in decapitated rat brain to decline to a level at which the brain becomes unconscious was estimated to be 2.7 sec. Assuming that decapitation is a powerful arousal stimulus and that the resulting EEG activation (low voltage, fast activity) indicates a conscious awareness of pain and distress the maximum time the pain and distress could be perceived would be 2.7 sec. Hence, decapitation of rats per se may be considered humane.

Stress-induced consumption of ethanol by rats.

Abstract The natural aversion of rats to ethanol was overcome by subjecting rats to immobilization stress for a two-week period during which increasing concentrations of ethanol were offered in the drinking water. The rats subjected to this regimen consumed 47% of total calories as ethanol, indefinitely, following removal of the stress. Ethanol was consumed at a rate of 17.1 g/kg body weight along with sufficient stock diet to assure adequate nutrition in the absence of ethanol.

Abatement by acetate of an ethanol withdrawal syndrome

Abstract Acetate, the main end product of ethanol metabolism in the liver and a substrate of the cerebral small-pool Krebs-cycle, was tested for its ability to abate an ethanol withdrawal syndrome. Male Sprague-Dawley derived rats were rendered physically dependent on ethanol by intragastric administration of ethanol at a dosage of 9 to 15 grams per kilogram per day over a 4-day period. Oral administration of acetate was effective in abating the tremulous component of the ethanol withdrawal syndrome.

The ethanol withdrawal syndrome: a consequence of lack of substrate for a cerebral Krebs-cycle

The hypothesis is advanced that the ethanol withdrawal syndrome is a manifestation of dependence by a cerebral Krebs-cycle on substrates which are readily available during ethanol addiction but which are relatively unavailable during withdrawal.

Restraint stress inhibited healing in rats

Abstract The healing rate, as measured by bursting strength in 5 days, of jejunal anastomoses in normal rats is reduced by restraint stress. The reduced healing rate is not mediated by a restraint-induced decrease in food and water intake.

Supression of an ethanol withdrawal syndrome in rats by 3-hydroxybutyrate

An ethanol withdrawal syndrome was elicited by withholding ethanol from physically dependent, male Sprague-Dawley rats. Ethanol dependence had been induced by intragastric administration of ethanol at a dosage of 9 to 15 grams per kilogram per day over a four-day period. Oral administration of 3-hydroxybutyrate, a compound which is elevated in blood of ethanol dependent rats and is a substrate of both the cerebral small-pool and large-pool Krebs-cycle, was effective in suppressing the tremulous component of the ethanol withdrawal syndrome. 3-Hydroxybutyrate did not function as a central nervous system depressant at the dose levels employed.

Suppression of an ethanol withdrawal syndrome in rats by butyrate, lactate and β-hydroxybutyrate

Butyrate, lactate and beta-hydroxybutyrate, compounds which may be elevated in blood of ethanol dependent rats and substrates of the cerebral small-pool Krebs-cycle, were tested for their ability to suppress an ethanol withdrawal syndrome. Male Sprague-Dawley rats were rendered physically dependent on ethanol by intragastric administration of ethanol at a dosage of 9 to 15 grams per kilogram per day over a 4-day period. Oral administration of a mixture of butyrate, lactate and beta-hydroxybutyrate was effective in suppressing the tremulous component of the ethanol withdrawal syndrome.

Chronic alcohol consumption during pregnancy: alleviation of untoward effects by adequate nutrition

Abstract In many investigations of the fetal alcohol syndrome, a liquid diet containing 36% of total calories as ethanol was fed to rats during pregnancy. Since this diet was considered nutritionally adequate, it was thought that the observed effects were due to the teratogenicity of alcohol. It is now known that rats maintained on this diet do not obtain required nutrition during gestation. Hence, the results obtained in the past are due to both malnutrition and alcohol. In some recent studies, pregnant rats were fed a diet containing less than 36% of total calories as alcohol. These diets provided both adequate nutrition and chronic alcohol administration during pregnancy. The results from these studies suggest a close association between nutritional status of the animal and the effects of alcohol ingestion. Unlike in the past, further studies on fetal alcohol syndrome can now be carried out in the absence of malnutrition to determine whether alcohol will exhibit any teratogenic effects.

Separation of the tremorous and muscular rigidity components of the ethanol withdrawal syndrome in the rat.

The alcohol withdrawal syndrome consists of a kinetic tremor, the tremorous component, and a peculiar abnormality of tone called asterixis, the muscular rigidity component. The severity of the ethanol withdrawal syndrome in the rat is generally assessed by the severity of the tremors. 3-Hydroxybutyrate suppresses the tremorous component but not the muscular rigidity component of the ethanol withdrawal syndrome, thus effectively differentiating the two components in the rat.

Prevention of alcohol toxicity by adequate nutrients: Mechanism and potential application

Abstract A high blood alcohol level is necessary but not sufficient for the expression of ethanols toxic effects on the liver, pancreas, etc. The 26% alcohol liquid diet apparently abates the toxic effects of ethanol observed when the 36% alcohol diet is fed to rats by holding the blood alcohol concentration below that achieved with the 36% alcohol diet. The objective of this study was to determine the mechanism whereby the 26% alcohol liquid diet holds down the blood alcohol level. The area under the blood alcohol concentration versus time curve (AUC) was measured in rats intubated with the 26% alcohol diet. From this data a power function relation relating dose of alcohol and the AUC was derived. The hourly ingestion of liquid diet by rats fed either the 26% or 36% liquid alcohol diet was determined for 42 hours. The quantity of ethanol ingested per kg body weight over the 42 h time period was not significantly different between rats fed the 26% and those fed the 36% alcohol diets. However, the blood alcohol concentrations after 34 h (2 AM) and 41 h (9 AM) and the AUC calculated by the power function relations from the temporal ingestion of the diets were significantly different between rats ingesting the 36% and 26% alcohol diets. The mechanism whereby the blood alcohol level is held down when the 26% alcohol diet is fed involves four factors. First, lower alcohol dose is necessarily ingested per volume of diet with the 26% alcohol diet than with the 36% alcohol diet. Second, this study showed that a significant decrease in the AUC occurs when the 26% alcohol diet is ingested compared to alcohol without diet. Third, the AUC is a nonlinear power function of the alcohol dose. And fourth, we found a temporal difference in the ingestion of the alcohol dose which results in a smaller calculated AUC when the 26% alcohol diet is fed than when the 36% alcohol diet is fed. First-pass alcohol metabolism which is increased by nutrients occurs in the human. It is therefore possible that the ingestion of a food bar, containing all nutrients in the proportions in which they are recommended for the human, simultaneous with the ingestion of each ethanol drink, would also result in significantly lower blood alcohol levels and hence reduced toxicity in the human.