A novel procedure for initiation of voluntary ethanol consumption in the rat was evaluated in terms of ease of initiation, consistency, and resulting brain ethanol levels. The "jello shot" consists of 10% ethanol in gelatin along with a caloric source (Polycose). Initiation of "jello shot" consumption in Sprague-Dawley rats required no food or water restriction and resulted in initial daily (8.4±0.6 g/kg body weight) and eventual hourly (1.1±0.1 g/kg body weight) intake of ethanol comparable to other procedures using either alcohol-preferring or non-genetically selected rats. Rat intake of ethanol via "jello shots" recovered quickly from environmental alterations and surgical implantation of a guide cannula. During 1-hr free access sessions, consumption of the "jello shot" occurred during the initial 10 minutes and resulted in a dose-related increase in ethanol levels in nucleus accumbens measured using microdialysis. These brain ethanol levels were comparable to those achieved using other selfadministration methods. However, when 0.5 g/kg ethanol was gavaged either in "jello shot" or saline, there was about a 20% decrease in brain ethanol concentrations after gavage of the "jello shot" compared to saline. Even so, lack of a need for initial food or water deprivation and the rapidity with which stable self-administration can be achieved both suggest utility of the "jello shot" as a completely voluntary ethanol procedure. Keywordsethanol self-administration; water deprivation; nucleus accumbens; gelatin; Polycose Alcohol ranks second only to tobacco in terms of the magnitude of adverse public health consequences of its abuse. It is important to develop animal models that emulate conditions of human abuse in order to study neural mechanisms implicated in the etiology of alcoholism. Animal models of alcoholism usually induce animals to drink sufficient quantities of ethanol by initial temporary food or water restriction to encourage rats to partake of unfamiliar tastes. For example, Czachowski et al. (1999) initiates ethanol consumption by providing the 10% ethanol solution as the only available fluid for three days before operant training. Additionally, the fluid received as a result of barpressing is the only fluid available during the first 5-7 days of operant training. Even when sucrose or saccharin is added to the ethanol solution to provide additional reinforcement, rats still need to be initially water deprived in order to encourage them to consume the novel sweet taste (reviewed in Samson & Czachowski 2004). Another 1 Mail proofs to:Joanna Peris, Ph.D. Department of Pharmacodynamics, Box 100487, University of Florida, Gainesville FL 32610, Phone: 352-392-9768, Fax: 352-392-9187, Email: peris@cop.ufl.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is pub...

Capillary electrophoresis coupled with laser-induced fluorescence detection (CE-LIF) provides 15-s temporal resolution of amino acid levels in microdialysate, which, for the first time, allows almost real time measurement of changes during episodes of behavior. We trained Sprague-Dawley rats to self-administer either 10% ethanol-containing gelatin or non-alcoholic gelatin in a typical operant chamber. After rats reached stable daily levels of responding, microdialysis probes were inserted into nucleus accumbens and samples were collected before, during and after operant sessions with on-line analysis via CE-LIF. During the first 15 min of the operant session, there was a significant increase in taurine that correlated with the amount of ethanol consumed (R2 = 0.81) but no change in rats responding for plain gel. There were large, consistent increases in glycine in both the ethanol and plain gel groups which correlated with the amount of gel consumed. A smaller increase was observed in rats with free non-operant access to plain gel compared to the increase seen with the same amount of gel consumed under operant conditions. When rats were given a time out after each delivery of gel in the operant protocol, the greatest increase of glycine was obtained with the longest time out period. Thus, increases in glycine in nucleus accumbens appear to be related to anticipation of reinforcement.

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