Increasing EtOH Concentration Research Articles

Cross‐Sensitization to Binge Alcohol Intake Following Binge Intake of Palatable Diets

Obesity and alcoholism, two of the most common chronic conditions in the United States, may be behaviorally linked as binge intake of palatable diets, such as diets high in fat (HFD), and binge alcohol (EtOH) intake may utilize similar neurocircuitry. We hypothesized that binge intake of one modality (i.e. HFD) may sensitize the shared neurocircuitry to further activation by another modality (i.e. EtOH). Therefore, we combined a binge HFD intake model in mice where HFD access is limited to one 24hr session per week (Limited Access HFD: LAH) with a patterned EtOH access schedule that also promotes binge‐like intake in a two‐bottle choice model (Limited Access EtOH: LAE; 4hrs/day, 4days/wk). Control mice were given the same EtOH access schedule but were given continuous ad libitum access to HFD (60% calories from fat) or control Chow diet (10% calories from fat). Six‐week old male C57Bl/6J mice were weight matched, individually housed, and assigned to HFD+LAE, Chow+LAE, or LAH+LAE groups (n=10 per group). All groups of mice were given increasing EtOH concentrations over the course of the study (10% EtOH for three weeks, 15% EtOH for two weeks, and 20% EtOH for two weeks). Body mass was measured daily while EtOH/water intake and EtOH preference were assessed after every drinking session. Over the course of the study, HFD+LAE mice gained significantly more weight than Chow+LAE or LAH+LAE mice (p=0.001; one‐way ANOVA). While weight gain was predominantly linear in HFD+LAE and Chow+LAE mice, LAH+LAE mice showed weight cycling indicating a binge‐like eating pattern. LAH+LAE mice consumed significantly more EtOH than Chow+LAE or HFD+LAE mice (p=0.001, repeated measures two‐way ANOVA), suggesting that binge intake of HFD led to increased binge EtOH intake patterns in LAH mice. LAH+LAE and Chow+LAE mice showed higher preference towards EtOH than HFD+LAE mice (p=0.001, repeated measures two‐way ANOVA). Together, these results suggest limited access to palatable diets induce binge‐like eating patterns that further cross‐sensitize to binge alcohol intake and mitigates the loss of alcohol preference in mice given continuous HFD.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

A comprehensive comparative study on morphology and pervaporative performance of porous-supported mesoporous zeolitic membranes

Abstract Mordenite (MOR) and faujasite (FAU) were formed as a membrane layer on tubular mullite and disk-shaped α-alumina supports for pervaporation (PV) dehydration of ethanol (EtOH). Structural analyses were carried out using XRD, SEM and EDAX. EtOH/water PV process was utilized to assess the membranes performances. The experiments show the fairly high separation factor representing the defect-free membrane layer and legible nonzeolitic pores on the top-layer. The effects of synthesis parameters including ceramic support, repetition of coating, seeding method, crystallization time (14 and 18 h) and temperature (160, 170 and 180 °C), and Si/Al ratio of the precursor gel formulation (12 and 16) on the membranes structures and their PV performances were investigated. Furthermore, the effective operational conditions (feed concentration (50, 70 and 90 wt% EtOH) and temperature (25 and 45 °C), and vacuum on permeate side (80 and 130 mmHg)) on PV performance of the membranes were studied. According to a combined performance parameter, pervaporation separation index (PSI), the MOR layer on α-alumina (MOR_D-II) can be reported as the best membrane for EtOH/water PV process. Permeation flux (43.43%), separation factor (30.39%) and PSI (62.35%) decrease with increasing EtOH concentration in feed (50–90 wt%). However, increasing feed temperature increases permeation flux and decreases separation factor, whereas applying higher vacuum in the permeate side leads to the opposite trend.

Specific polarizability of sand-clay mixtures with varying ethanol concentration.

We utilise a concept of specific polarizability (c s ), represented as the ratio of mineral-fluid interface polarization per pore-normalised surface area S p , to demonstrate the influence of clay-organic interaction on complex conductivity measurements. Complex conductivity measurements were performed on kaolinite- and illite-sand mixtures as a function of varying ethanol (EtOH) concentration (10% and 20% v/v). The specific surface area of each clay type and Ottawa sand was determined by nitrogen-gas-adsorption Brunauer-Emmett-Teller method. We also calculated the porosity and saturation of each mixture based on weight loss of dried samples. Debye decomposition, a phenomenological model, was applied to the complex conductivity data to determine normalised chargeability (m n ). Specific polarizability estimates from previous complex conductivity measurements for bentonite-sand mixtures were compared with our dataset. The c s for all sand-clay mixtures decreased as the EtOH concentration increased from 0% to 10% to 20% v/v. We observe similar c s responses to EtOH concentration for all sand-clay mixtures. Analysis of variance with a level of significance α = 0.05 suggests that the suppression in c s responses with increasing EtOH concentration was statistically significant for all sand-clay mixtures. On the other hand, real conductivity showed only 10% to 20% v/v changes with increasing EtOH concentration. The c s estimates reflect the sensitivity of complex conductivity measurements to alteration in surface chemistry at available surface adsorption sites for different clay types, likely resulting from ion exchange at the clay surface and associated with kinetic reactions in the electrical double layer of the clay-water-EtOH media. Our results indicate a much larger influence of specific surface area and ethanol concentration on clay-driven polarization relative to changes in clay mineralogy.

Functional Upregulation of STIM-1/Orai-1-Mediated Store-Operated Ca2+ Contributing to the Hypertension Development Elicited by Chronic EtOH Consumption.

Chronic ethanol (EtOH) consumption has been associated with deleterious effects on the cardiovascular system by abnormal calcium (Ca2+) handling. Store-operated Ca2+ entry (SOCE) is related to cardiovascular remodeling which leads to the hypertension development, and the coupling between STIM-1 (ER Ca2+ sensor) and Orai-1 (channel pore) is a key mechanism to control SOCE through of store-operated Ca2+ channels (SOCCs). However, the role of STIM-1/Orai-1-mediated SOCE and its cross-talk with EtOH-triggered vascular remodeling and hypertension remain poorly understood. We address this subject in the present study by evaluating how chronic EtOH consumption induces alterations in Ca2+ handling via SOCE. Male Wistar Kyoto (WKY) and Spontaneously Hypertensive (SHR) rats were subjected to the intake of increasing EtOH concentrations (5-20%, for 30 days). Systolic blood pressure (SBP) and EtOH concentration were measured; cardiovascular remodeling was assessed by histomorphometry; and function/ expression of STIM-1/Orai-1-mediated Ca2+ influx were evaluated by isometric contraction and western blot experiments. Compared to the WKY-Control, our results show that: (1) chronic EtOH consumption caused a significant elevation of SBP in both strains; (2) cardiac hypertrophy and hypertrophic aortic wall remodeling much more pronounced in WKY-EtOH; (3) decreased capacity of ER to store and release Ca2+; (4) increased STIM-1/Orai-1-mediated SOCCs activation, which was selectively inhibited by YM-58483; and (5) increased expression of STIM-1 in WKY-EtOH and SHR-Control rats. These findings suggest that hypertrophic aortic remodeling and abnormal contraction triggered mainly by Ca2+ overload via STIM-1/Orai-1-mediated SOCE through SOCCs are involved hypertension developed by EtOH consumption.

Functional Upregulation of STIM‐1/Orai‐1‐Mediated Store‐Operated Ca2+ Entry Contributing to the Aortic Remodeling and Hypertension Development by Chronic EtOH Consumption

Chronic ethanol (EtOH) consumption has been associated with deleterious effects on the cardiovascular system by abnormal calcium (Ca2+) handling. Store‐operated Ca2+ entry (SOCE) is related to cardiovascular remodeling which leads to the hypertension development, and the coupling between STIM‐1 (Ca2+ sensor) and Orai‐1 (channel pore) is a key mechanism to control SOCE through of store‐operated Ca2+ channels (SOCCs). However, the role of STIM‐1/Orai‐1‐mediated SOCE and its cross‐talk with EtOH‐triggered vascular remodeling and hypertension remain poorly understood. We address this subject in the present study by evaluating how chronic EtOH consumption induces alterations in Ca2+ handling via SOCE. Male Wistar Kyoto (WKY) and Spontaneously Hypertensive (SHR) rats were subjected to the intake of increasing EtOH concentrations (5–20%, for 30 days). Systolic blood pressure (SBP) and EtOH concentration were measured; cardiovascular remodeling was assessed by histomorphometry; and function/expression of STIM‐1/Orai‐1‐mediated Ca2+ influx were evaluated by isometric contraction and western blot experiments. Compared to the WKY‐Control, our results show that: (1) chronic EtOH consumption caused a significant elevation of SBP in both strains; (2) cardiac hypertrophy and hypertrophic aortic wall remodeling much more pronounced in WKY‐EtOH; (3) decreased capacity of reticulum to store and release Ca2+; (4) increased STIM‐1/Orai‐1‐mediated SOCCs activation, which was selectively inhibited by YM‐58483; and (5) increased expression of STIM‐1 in WKY‐EtOH and SHR‐Control rats. These findings suggest that hypertension developed by EtOH consumption has as one of its origins the hypertrophic aortic remodeling and abnormal contraction triggered mainly by Ca2+ overload via STIM‐1/Orai‐1‐mediated SOCE through SOCCs.Support or Funding InformationThis work was supported by the Fundação Coordenação de Aperfeiçoamento de Pessoal de Nível Superior‐CAPES (BEX 8477/13‐2); the Fundação de Amparo a Pesquisa do Estado de São Paulo‐FAPESP (2014/01569‐0); the Ministerio de Economía y Competitividad, España (SAF: 2013‐44108‐P and FPI BES‐2014‐069005).

Electrophysiological properties and augmented catecholamine release from chromaffin cells of WKY and SHR rats contributing to the hypertension development elicited by chronic EtOH consumption

It is known that chronic ethanol (EtOH) consumption leads to hypertension development and has been associated with deleterious effects on the cardiovascular system. Whether this condition alters calcium (Ca2+) signaling and exocytosis in adrenal chromaffin cells (CCs) as the case is for genetic hypertension, is unknown. We explored this question in four randomized experimental groups, male Wistar Kyoto (WKY/EtOH) and Spontaneously Hypertensive (SHR/EtOH) rats were subjected to the intake of increasing EtOH concentrations (5–20%, for 30 days) and their respective controls (WKY/Control and SHR/Control) received water. WKY/EtOH developed hypertension and cardiac hypertrophy; blood aldehyde dehydrogenase (ALDH) and H2O2 were also augmented. In comparison with WKY/Control, CCs from WKY/EtOH had the following features: (i) depolarization and higher frequency of spontaneous action potentials; (ii) decreased Ca2+ currents with slower inactivation; (iii) decreased K+ currents; (iv) augmented K+-elicited cytosolic Ca2+ transients ([Ca2+]c); (v) enhanced K+-elicited catecholamine release. These cardiovascular, blood and CCs changes were qualitatively similar to those undergone by SHR/Control and SHR/EtOH. The results suggest that the hypertension elicited by chronic EtOH has pathogenic features common to genetic hypertension namely, augmented [Ca2+]c transients and catecholamine release from their CCs.

Oral operant ethanol self-administration in the absence of explicit cues, food restriction, water restriction and ethanol fading in C57BL/6J mice.

Mouse models of ethanol (EtOH) self-administration are useful to identify genetic and biological underpinnings of alcohol use disorder. These experiments developed a novel method of oral operant EtOH self-administration in mice without explicitly paired cues, food/water restriction, or EtOH fading. Following magazine and lever training for 0.2 % saccharin (SAC), mice underwent nine weekly overnight sessions with lever pressing maintained by dipper presentation of 0, 3, 10, or 15 % EtOH in SAC or water vehicle. Ad libitum water was available from a bottle. Water vehicle mice ingested most fluid from the water bottle in contrast to SAC vehicle mice, which despite lever pressing demands, drank most of their fluid from the liquid dipper. Although EtOH in SAC vehicle mice showed concentration-dependent increases of g/kg EtOH intake, lever pressing decreased with increasing EtOH concentration and did not exceed that of SAC vehicle alone at any EtOH concentration. Mice reinforced with EtOH in water ingested less EtOH than mice reinforced with EtOH in SAC. EtOH in water mice, however, showed concentration-dependent increases in g/kg EtOH intake and lever presses. Fifteen percent EtOH in water mice showed significantly greater levels of lever pressing than water vehicle mice and a significant escalation of responding across weeks of exposure. Naltrexone pretreatment reduced EtOH self-administration and intake in these mice without altering responding in the vehicle control condition during the first hour of the session. SAC facilitated EtOH intake but prevented observation of EtOH reinforcement. Water vehicle unmasked EtOH's reinforcing effects.

Molecular mechanisms of action of different concentrations of ethanol in water on ordered structures of intercellular lipids and soft keratin in the stratum corneum

Ethanol (EtOH) is one of the bases in topically applied medicines that promote the skin permeation of drugs. Although the effects of EtOH have been attributed to structural modifications in the stratum corneum, the underlying mechanisms, especially the influence of different concentrations of EtOH, have not been examined extensively. Structural modifications in the stratum corneum of hairless mouse due to the application of EtOH/water mixture were herein investigated at the molecular level using synchrotron X-ray diffraction. The results revealed that all EtOH concentrations examined greatly modified the short lamellar structures containing the aqueous layer in intercellular lipids and the structure of keratin fibrils in corneocytes, which can take up hydrophilic compounds. However, the long lamellar and the hydrocarbon-chain packing structures were unaffected by EtOH. Changes to the short lamellar structures were not proportional to the concentration of EtOH. However, the keratin fibril structures changed gradually with increasing EtOH concentration. The X-ray diffraction experiments enabled the effects of different EtOH concentrations on the morphology of the stratum corneum to be assessed by using a number of experimental samples to avoid variations due to individual differences. The results indicated that alterations to the short lamellar structures appeared to be related to the skin permeability of drugs with the application of EtOH/water mixture, and monotonous structural changes in the keratin fibrils with an increase in EtOH concentration may contribute to this permeation as supplement. These results will be useful for the development of new drug formulations containing EtOH.

Time-Course of Neuroendocrine Changes and Its Correlation with Hypertension Induced by Ethanol Consumption

Ethanol (ETOH) consumption has been associated with endocrine and autonomic changes, including the development of hypertension. However, the sequence of pathophysiological events underlying the emergence of this effect is poorly understood. This study aimed to establish a time-course correlation between neuroendocrine and cardiovascular changes contributing to the development of hypertension following ETOH consumption. Male adult Wistar rats were subjected to the intake of increasing ETOH concentrations in their drinking water (first week: 5%, second week: 10%, third and fourth weeks: 20% v/v). ETOH consumption decreased plasma and urinary volumes, as well as body weight and fluid intake. Furthermore, plasma osmolality, plasma sodium and urinary osmolality were elevated in the ETOH-treated rats. ETOH intake also induced a progressive increase in the mean arterial pressure (MAP), without affecting heart rate. Initially, this increase in MAP was correlated with increased plasma concentrations of adrenaline and noradrenaline. After the second week of ETOH treatment, plasma catecholamines returned to basal levels, and incremental increases were observed in plasma concentrations of vasopressin (AVP) and angiotensin II (ANG II). Conversely, plasma oxytocin, atrial natriuretic peptide, prolactin and the hypothalamus-pituitary-adrenal axis components were not significantly altered by ETOH. Taken together, these results suggest that increased sympathetic activity may contribute to the early increase in MAP observed in ETOH-treated rats. However, the maintenance of this effect may be predominantly regulated by the long-term increase in the secretion of other circulating factors, such as AVP and ANG II, the secretion of both hormones being stimulated by the ETOH-induced dehydration.

Complex resistivity signatures of ethanol in sand–clay mixtures

We performed complex resistivity (CR) measurements on laboratory columns to investigate changes in electrical properties as a result of varying ethanol (EtOH) concentration (0% to 30% v/v) in a sand-clay (bentonite) matrix. We applied Debye decomposition, a phenomenological model commonly used to fit CR data, to determine model parameters (time constant: τ, chargeability: m, and normalized chargeability: mn). The CR data showed a significant (P≤0.001) time-dependent variation in the clay driven polarization response (~12 mrad) for 0% EtOH concentration. This temporal variation probably results from the clay-water reaction kinetics trending towards equilibrium in the sand-clay-water system. The clay polarization is significantly suppressed (P≤0.001) for both measured phase (ϕ) and imaginary conductivity (σ″) with increasing EtOH concentration. Normalized chargeability consistently decreases (by up to a factor of ~2) as EtOH concentration increases from 0% to 10% and 10 to 20%, respectively. We propose that such suppression effects are associated with alterations in the electrical double layer (EDL) at the clay-fluid interface due to (a) strong EtOH adsorption on clay, and (b) complex intermolecular EtOH-water interactions and subsequent changes in ionic mobility on the surface in the EDL. Changes in the CR data following a change of the saturating fluid from EtOH 20% to plain water indicate strong hysteresis effects in the electrical response, which we attribute to persistent EtOH adsorption on clay. Our results demonstrate high sensitivity of CR measurements to clay-EtOH interactions in porous media, indicating the potential application of this technique for characterization and monitoring of ethanol contamination in sediments containing clays.

Electrical signatures of ethanol–liquid mixtures: Implications for monitoring biofuels migration in the subsurface

Ethanol (EtOH), an emerging contaminant with potential direct and indirect environmental effects, poses threats to water supplies when spilled in large volumes. A series of experiments was directed at understanding the electrical geophysical signatures arising from groundwater contamination by ethanol. Conductivity measurements were performed at the laboratory scale on EtOH-water mixtures (0 to 0.97 v/v EtOH) and EtOH-salt solution mixtures (0 to 0.99 v/v EtOH) with and without a sand matrix using a conductivity probe and a four-electrode electrical measurement over the low frequency range (1-1000 Hz). A Lichtenecker-Rother (L-R) type mixing model was used to simulate electrical conductivity as a function of EtOH concentration in the mixture. For all three experimental treatments increasing EtOH concentration resulted in a decrease in measured conductivity magnitude (|σ|). The applied L-R model fitted the experimental data at concentration ≤0.4v/v EtOH, presumably due to predominant and symmetric intermolecular (EtOH-water) interaction in the mixture. The deviation of the experimental |σ| data from the model prediction at higher EtOH concentrations may be associated with hydrophobic effects of EtOH-EtOH interactions in the mixture. The |σ| data presumably reflected changes in relative strength of the three types of interactions (water-water, EtOH-water, and EtOH-EtOH) occurring simultaneously in EtOH-water mixtures as the ratio of EtOH to water changed. No evidence of measurable polarization effects at the EtOH-water and EtOH-water-mineral interfaces over the investigated frequency range was found. Our results indicate the potential for using electrical measurements to characterize and monitor EtOH spills in the subsurface.

Ethanol Increases Fetal Human Neurosphere Size and Alters Adhesion Molecule Gene Expression

Ethanol (ETOH) consumption by pregnant women can result in Fetal Alcohol Spectrum Disorder (FASD). To date, the cellular targets and mechanisms responsible for FASD are not fully characterized. Our aim was to determine if ETOH can affect fetal human brain-derived neural progenitor cells (NPC). Neural progenitor cells were isolated by positive selection from normal second trimester fetal human brains (n = 4) and cultured, for up to 72 hours, in mitogenic media containing 0, 1, 10, or 100 mM ETOH. From 48 to 72 hours in culture, neurospheres generated in these conditions were filmed using time-lapse video microscopy. At the end of 72 hours, neurosphere diameter and roundness were measured using videographic software. Mitotic phase analysis of cell-cycle activity and apoptotic cell count were also performed at this time, by flow cytometry using propidium iodide (PI) staining. Real-time PCR was used to estimate expression of genes associated with cell adhesion pathways. Neurosphere diameter correlated positively (r = 0.87) with increasing ETOH concentrations. There was no significant difference in cell-cycle activity and no significant increase in apoptosis with increasing ETOH concentrations. Time-lapse video microscopy showed that ETOH (100 mM) reduced the time for neurosphere coalescence. Real-time PCR analysis showed that ETOH significantly altered the expression of genes involved in cell adhesion. There was an increase in the expression of alpha and beta Laminins 1, beta Integrins 3 and 5, Secreted phosphoprotein1 and Sarcoglycan epsilon. No change in the expression of beta Actin was observed while the expression of beta Integrin 2 was significantly suppressed. ETOH had no effect on NPC apoptosis but, resulted in more rapid coalescence and increased volume of neurospheres. Additionally, the expression of genes associated with cell adhesion was significantly altered. ETOH induced changes in NPC surface adhesion interactions may underlie aspects of neurodevelopmental abnormalities in FASD.

Enhanced ex vivo buccal transport of propranolol: evaluation of phospholipids as permeation enhancers.

The aim of the present study was to evaluate the effects of two phospholipid permeation enhancers, lysophosphatidylcholine (LPC) and didecanoylphosphatidylcholine (DDPC), along with a fusidic acid derivative, sodium taurodihydrofusidate (STDHF) and ethanol (EtOH) on the buccal transport of propranolol hydrochloride (PPL) using an ex vivo buccal diffusion model. The permeation rate of [3H]PPL as measured by steady-state fluxes increased with increasing EtOH concentration. A significant flux enhancement (P<0.05) was achieved by EtOH at 20 and 30 %v/v concentrations. At a 0.5 %w/v permeation enhancer concentration, the buccal permeation of [3H]PPL was significantly enhanced by all the enhancers studied (i.e., LPC, DDPC and STDHF) compared to the control (phosphate-buffered saline pH 7.4, PBS). LPC and DDPC displayed a greater degree of permeation enhancement compared with STDHF and EtOH-PBS mixtures with an enhancement ratio of 3.2 and 2.9 for LPC and DDPC, respectively compared with 2.0 and 1.5 for STDHF and EtOH:PBS 30:70 %v/v mixture, respectively. There was no significant difference between LPC and DDPC for the flux values and apparent permeability coefficients of [3H]PPL. These results suggest that phospholipids are suitable as permeation enhancers for the buccal delivery of drugs.

Influence of ethanol on the thickness and free energy of film formation of DMPC foam films

Foam films prepared from 1,2-dimirystoil-sn-glycero-3-phosphorylcholine (DMPC) dispersions in water–ethanol mixtures were investigated. Their thickness and contact angle (foam film/meniscus) were measured. Experimental results show that an increase of EtOH concentration in the film forming dispersions leads to a decrease in the film thickness. At EtOH concentrations above 40% v/v the foam films have a bilayer structure without any noticeable core of solvent. The film thickness remains constant with the further increasing of the EtOH concentration up until 50% v/v. This behaviour is corroborated by the strong increase in the contact angles (a decrease in the free energy of film formation) with increasing EtOH concentration. Ellipsometric measurements on the thickness of adsorbed DMPC monolayers and surface pressure isotherms of DMPC spread on the water–ethanol subphases show that the effective area per lipid molecule decreases, resulting in a larger monolayer thickness, when the EtOH concentration in the subphase is increased. An increase of the EtOH concentration leads to a dehydration of the DMPC molecules and a reduction in strength and range of the repulsive hydration force between the film monolayers. The film thickness and the free energy of film formation are governed by the balance of the van der Waals attraction and the repulsive hydration force between the foam film surfaces.

Comparison of ethanol and trichloracetic acid fractionation for measurement of proteolysis in Emmental cheese

Abstract Crude fractionation of cheese by various precipitants and subsequent determination of soluble nitrogen (N) represents a well-established method for quantification of proteolysis in cheese. Attempts have been made to replace precipitation with 12% trichloracetic acid (TCA) by fractionation with differing concentrations of ethanol (EtOH). In order to compare these procedures, aqueous extracts of Emmental cheeses were fractionated with EtOH at concentrations ranging from 30 to 70%. N recovery increased significantly with increasing cheese age and, for each cheese, decreased with increasing EtOH concentration. For young cheese, precipitation with 30–40% EtOH gave comparable results to fractionation with 12% TCA. For mature cheese, however, 70% EtOH was necessary to achieve N values corresponding to precipitation with 12% TCA. Analytical ultrafiltration of aqueous cheese extracts and N recovery in fractions thereof prepared by TCA and EtOH, as well as SDS-PAGE and RP-HPLC of the EtOH-soluble and EtOH-insoluble fractions, showed that variations in cut-off levels can be attributed to qualitative differences in extract composition.

Ethanol intake during scheduled and non-scheduled food presentations

Ethanol (ETOH) intake baselines were obtained using a continuous, two-choice presentation of one of a series of increasing ETOH concentrations and water. Following the development of stable water intakes using a schedule-induced polydipsia (SIP) procedure, increasing concentrations of ETOH were repeated in the operant chamber. This was followed by a reinstatement of the pre-polydipsia home cage procedures. It was found that: 1) scheduled delivery of food slightly lowered or did not change ETOH intake in contrast to non-scheduled presentations, 2) during non-scheduled food presentations, maximum ETOH intakes occured at higher concentrations than during scheduled presentations, and 3) post polydipsia water intakes were increased over pre-polydipsia baseline intakes. Because of these findings it was concluded that the use of SIP procedures to generate increased ETOH intakes appears to be questionable and comparisons between home cage (non-scheduled food) and SIP (scheduled food) ETOH intakes are not appropriate due to the different self-section functions for ETOH. These findings may be due to the different hydrational states of the animals when water is available in addition to ETOH (home cage) versus forced ETOH presentation (SIP).