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fourth day. Control animals are maintained under similar conditions but are fed the ISOMIL diet without ethanol. This method can be associated with significant mortality (9-23%; N'Gouemo et al., 1996).

Inhalation

Alcohol intoxication is initiated by administration of a loading dose of ethanol (1.6g/kg; 8%, wt/vol). Some investigators administer the alcohol dehydrogenase inhibitor pyrazole to enhance and stabilize the blood ethanol concentrations (Goldstein and Pal, 1971). Animals are then placed in a closed inhalation chamber as illustrated in Figure 1, and alcohol dependence is induced by continuous exposure to alcohol vapors for 2 to 7 days. Air is continuously delivered to the chamber at a rate of 10 liters per minute to provide for the respiratory need of the animals. Ethanol (95%) is evaporated into the air so that the experimental chamber holding the animal receives air with an ethanol concentra tion of 7 to 35 mg/liter. Control chambers are similarly configured, but with the absence of ethanol vapor.

Liquid Diet

Alcohol can also be chronically administered in a liquid diet. Rats have an aversion to alcohol. However, high alcohol intake can be induced with a nutritionally complete liquid diet used as the only food source, such as the Lieber-DeCarli diet (Dyets, Inc., Bethlehem, PA) (Lieber and DeCarli, 1982). Control animals receive a similar diet in which an isocaloric amount of maltose is substituted for ethanol. The ethanol concentration is typically 6 to 7% (vol/vol) and is administered for 4 to 21 days. At the end of the alcohol exposure period, animals are switched to a regular diet. Mice can be treated with a similar diet, but the ethanol concentration may be lower (4.5 to 6.5%) and the exposure period is typically 2 to 6 days. Mice can also be "kindled" by repeated withdrawal (periods of 1 to 2 days of

FIGURE 1 Schematic representation of a system for administration of ethanol by inhalation modified after Ruwe et al. (1986). Ethanol (95%) is delivered by a solvent metering pump into a 250-ml vaporization chamber. The airtight vaporization chamber is maintained at 37° C by a water bath. Air is delivered into the vaporization chamber with an air pump to provide a flow rate of 2.5 to 4 liters per minute. Animals are exposed to ethanol-vapor concentrations of 7 to 35 mg/liter of air in a Plexiglas experimental chamber. A food tray and water bottle are securely affixed to the experimental chamber, giving the animal free access to food and water. The sample port allows air within the experimental chamber to be sampled for determination of ethanol concentrations. (See color insert.)

FIGURE 1 Schematic representation of a system for administration of ethanol by inhalation modified after Ruwe et al. (1986). Ethanol (95%) is delivered by a solvent metering pump into a 250-ml vaporization chamber. The airtight vaporization chamber is maintained at 37° C by a water bath. Air is delivered into the vaporization chamber with an air pump to provide a flow rate of 2.5 to 4 liters per minute. Animals are exposed to ethanol-vapor concentrations of 7 to 35 mg/liter of air in a Plexiglas experimental chamber. A food tray and water bottle are securely affixed to the experimental chamber, giving the animal free access to food and water. The sample port allows air within the experimental chamber to be sampled for determination of ethanol concentrations. (See color insert.)

abstinence during the chronic ethanol feeding), which potentiates the severity of withdrawal seizures (Becker and Hale, 1993; Pinel, 1980; Ripley et al., 2002).

Blood Sampling and Measurement of Blood Alcohol Concentrations

Blood alcohol concentrations are typically measured during intoxication, at the onset of withdrawal symptoms, and during the fully developed withdrawal syndrome. Blood samples are usually collected from the tail vein in mice or by intracardiac sampling in deeply anesthetized rats using large-bore (21-gauge) needles to prevent hemolysis. Blood samples are stored in tubes containing heparin or the anticoagulant potassium oxalate and sodium fluoride (Becton Dickinson Vacutainer Systems, Rutherford, NJ). Blood ethyl alcohol concentrations are measured using gas chromatog-raphy (Brown and Long, 1988) or determined in the plasma using the alcohol dehydrogenase method, which requires a spectrophotometer to measure the absorbance at 340 nm (Pointe Scientific, Canton, MI).

Seizure Monitoring Following Alcohol Withdrawal

Spontaneous Seizures

On administration of the last dose of ethanol, the animals are placed in a Plexiglas observation chamber located in a sound-attenuated room (Gonzalez et al., 1989). The behavior of each animal is recorded on videotape at 30 frames per second for about 84 hours from the time of ethanol discontinuation. The videotapes are scanned at high speed to identify segments with evidence of seizure-like behavior and then at slower speeds for scoring. The incidence and severity of the following behaviors are recorded: (1) myoclonic jerks of the head or trunk; (2) jumping episodes; (3) generalized tonic-clonic seizures consisting of loss of upright posture and repetitive extension and retraction of the limbs and trunk; and (4) rigid, tonic extension of the limbs. Myoclonic jerks occur most frequently during the first 6 hours following alcohol withdrawal. The incidence of generalized tonic-clonic seizures is maximal between 24 and 60 hours after alcohol withdrawal; tonic seizures are most frequent at 60 to 84 hours following withdrawal.

Audiogenic Seizures

Mice and rats subjected to alcohol withdrawal are susceptible to AGS between 10 and 26 hours following the last doses of alcohol (Freund, 1969; Riaz and Faingold, 1994). AGSs are induced in a sound-attenuating chamber using an electric bell that produces a sound volume of about 122 dB at the middle of the acoustic chamber. The bell tone is presented either until a seizure is triggered or for 60 seconds.

The animal's behavior is recorded on videotape for subsequent review. The incidence and type of seizures (wild running, bouncing clonus, tonic) are noted, and the overall severity is scored according to the scale of Jobe et al. (1973) (Table 2) and also Chapter 20). Audiogenic seizures can be measured repeatedly in the same animal with high interrater reliability.

Handling-Induced Convulsions

Mice are observed for seizure activity in response to various degrees of stimulation. Animals that exhibit spontaneous seizures or a tonic-clonic seizure within seconds of being handled during removal from their home cages receive the highest seizure scores. If no seizure occurs immediately with routine handling, animals are picked up by the tail and observed for an additional 2 seconds. If they still fail to exhibit a seizure, they are gently spun by the tail through a 180- to 360-degree arc. A score is assigned as defined in Table 3 based on the degree of stimulation required to elicit the seizure (handling alone, tail lift, or spinning) and the type of seizure (clonic, tonic, tonic-clonic) (Becker et al., 1997; Crabbe and Kosobud, 1990; Goldstein and Pal, 1971). HIC can be measured repeatedly in the same animal with high interrater reliability.

TABLE 2 Behavioral Rating Scale for Audiogenic Seizures

Score

Description of Behavior

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Beat The Battle With The Bottle

Beat The Battle With The Bottle

Alcoholism is something that can't be formed in easy terms. Alcoholism as a whole refers to the circumstance whereby there's an obsession in man to keep ingesting beverages with alcohol content which is injurious to health. The circumstance of alcoholism doesn't let the person addicted have any command over ingestion despite being cognizant of the damaging consequences ensuing from it.

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