PMID- 19932691 OWN - NLM STAT- MEDLINE DCOM- 20100330 LR - 20211020 IS - 1872-6240 (Electronic) IS - 0006-8993 (Print) IS - 0006-8993 (Linking) VI - 1310 DP - 2010 Jan 15 TI - Phasic and tonic fluctuations in brain, muscle, and skin temperatures during motivated drinking behavior in rats: physiological correlates of motivation and reward. PG - 87-102 LID - 10.1016/j.brainres.2009.11.036 [doi] AB - Since brain metabolism is accompanied by heat production, measurement of brain temperature offers a method for assessing global alterations in metabolic neural activity. This approach, high-resolution (5-s bin) temperature recording from the nucleus accumbens (NAcc), temporal muscle, and facial skin, was used to study motivated drinking behavior in rats. Experienced animals were presented with a cup containing 5-ml of Coca-Cola(R) (Coke) beverage that resulted, within certain latencies, in initiation of a continuous chain of licking until all liquid was fully consumed. While cup presentation induced rapid, gradual NAcc temperature increase peaking at the start of drinking, temperatures slowly decreased during Coke consumption, but phasically increased again in the post-consumption period when rats were hyperactive, showing multiple interactions with an empty cup. Muscle temperatures followed a similar pattern, but the changes were weaker and delayed compared to those in the brain. Skin temperature rapidly dropped after cup presentation, steadily maintained at low levels during consumption, and slowly restored during the post-consumption period. Substitution of the expected Coke with either sugar-free Diet Coke(R) or water resulted in numerous drinking attempts but ultimately no consumption. During these tests, locomotor activation was much greater and more prolonged, brain and muscle temperatures increased monophasically, and their elevation was significantly greater than that with regular Coke tests. Food deprivation decreased drinking latencies, did not change the pattern of temperature fluctuations during Coke consumption, but temperature elevations were greater than in controls. Our data suggest sustained neural activation triggered by appetitive stimuli and associated with activational (seeking) aspects of appetitive motivated behavior. This seeking-related activation is rapidly ceased following consumption, suggesting this change as a neural correlate of reward. In contrast, inability to obtain an expected reward maintains neural activation and seeking behavior, resulting in larger deviations in physiological parameters. CI - Published by Elsevier B.V. FAU - Smirnov, Michael S AU - Smirnov MS AD - Behavioral Neuroscience Branch, National Institute on Drug Abuse-Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD 21224, USA. FAU - Kiyatkin, Eugene A AU - Kiyatkin EA LA - eng GR - ZIA DA000445-09/ImNIH/Intramural NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Intramural DEP - 20091122 PL - Netherlands TA - Brain Res JT - Brain research JID - 0045503 RN - 0 (Sweetening Agents) SB - IM MH - Analysis of Variance MH - Animals MH - Body Temperature/*physiology MH - Drinking Behavior/*physiology MH - Food Preferences/physiology MH - Locomotion/physiology MH - Male MH - Motivation/*physiology MH - Muscle, Skeletal/*physiology MH - Nucleus Accumbens/*physiology MH - Rats MH - Rats, Long-Evans MH - Regression Analysis MH - *Reward MH - Skin Temperature MH - Sweetening Agents/administration & dosage MH - Time Factors PMC - PMC2812610 MID - NIHMS160951 EDAT- 2009/11/26 06:00 MHDA- 2010/03/31 06:00 PMCR- 2011/01/15 CRDT- 2009/11/26 06:00 PHST- 2009/08/12 00:00 [received] PHST- 2009/11/15 00:00 [revised] PHST- 2009/11/17 00:00 [accepted] PHST- 2009/11/26 06:00 [entrez] PHST- 2009/11/26 06:00 [pubmed] PHST- 2010/03/31 06:00 [medline] PHST- 2011/01/15 00:00 [pmc-release] AID - S0006-8993(09)02490-1 [pii] AID - 10.1016/j.brainres.2009.11.036 [doi] PST - ppublish SO - Brain Res. 2010 Jan 15;1310:87-102. doi: 10.1016/j.brainres.2009.11.036. Epub 2009 Nov 22.