1
|
Tapp DN, Zerkle HL, McMurray MS. Extent of food restriction affects probability but not delay-based decision-making. J Exp Anal Behav 2020; 114:179-192. [PMID: 32776567 DOI: 10.1002/jeab.624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 07/10/2020] [Accepted: 07/12/2020] [Indexed: 11/11/2022]
Abstract
Rodent studies on decision-making often use food rewards and food-restrict subjects in order to motivate performance. However, food restriction has widespread effects on brain and behavior, which depend on factors including extent of restriction and feeding schedule. These factors are well recognized for their effects on motivation, but may also cause effects on decision-making independent of motivation. We examined how the degree of weight-based food restriction in rats influenced decision-making on the probability and delay discounting tasks. Additionally, we examined how the method of food restriction (consistent amount vs. time constrained feeding schedule) influenced decision-making. Our results showed that the degree of weight-based food restriction significantly altered probability, but not delay discounting, and that these effects were not entirely explainable by differences in motivation. Additionally, the method of food restriction did not significantly influence discounting when animals were within the same range of weight-based restriction. Together, our findings suggest that the degree of food restriction may modulate the neural circuitry responsible for selective aspects of decision-making related to probability. Further, these data support the need for tight control and reporting of weight and feeding in studies relying on food restriction, and suggest that the effects of food restriction may be broader than previously considered.
Collapse
|
2
|
Campos GV, de Noronha SR, de Souza AA, Lima PM, Abreu AR, Chianca-Jr D, de Menezes RC. Estrogen receptor β activation within dorsal raphe nucleus reverses anxiety-like behavior induced by food restriction in female rats. Behav Brain Res 2018; 357-358:57-64. [PMID: 29567265 DOI: 10.1016/j.bbr.2018.03.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 02/15/2018] [Accepted: 03/15/2018] [Indexed: 02/06/2023]
Abstract
Severe food restriction (FR), as observed in disorders like anorexia nervosa, has been associated to the reduction of estrogen levels, which in turn could lead to anxiety development. Estrogen receptors, mainly ERβ type, are commonly found in the dorsal raphe nucleus (DRN) neurons, an important nucleus related to anxiety modulation and the primary source of serotonin (5-HT) in the brain. Taking together, these findings suggest an involvement of estrogen in anxiety modulation during food restriction, possibly mediated by ERβ activation in serotonergic DRN neurons. Thus, the present study investigated the relationship between food restriction and anxiety-like behavior, and the involvement of DRN and ERβ on the modulation of anxiety-like behaviors in animals subjected to FR. For that, female Fischer rats were grouped in control group, with free access to food, or a FR group, which received 40% of control intake during 14 days. Animals were randomly treated with 17β-estradiol (E2), DPN (ERβ selective agonist), or their respective vehicles, PBS and DMSO. Behavioral tests were performed on Elevated T-Maze (ETM) and Open Field (OF). Our results suggest that FR probably reduced the estrogen levels, since the remained in the non-ovulatory cycle phases, and their uterine weight was lower when compared to control group. The FR rats showed increased inhibitory avoidance latency in theETM indicating that FR is associated with the development of an anxiety-like state. The injections of both E2 and DPN into DRN of FR animals had an anxiolytic effect. Those data suggest thatanxiety-like behavior induced by FR could be mediated by a reduction of ERβ activation in the DRN neurons, probably due to decreased estrogen levels.
Collapse
Affiliation(s)
- Glenda Viggiano Campos
- Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, MG, Brazil; Graduate Program in Biological Sciences CBIOL/NUPEB, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Sylvana Rendeiro de Noronha
- Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, MG, Brazil; Graduate Program in Biological Sciences CBIOL/NUPEB, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Aline Arlindo de Souza
- Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, MG, Brazil; Graduate Program in Biological Sciences CBIOL/NUPEB, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Paulo Marcelo Lima
- Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, MG, Brazil; Graduate Program in Biological Sciences CBIOL/NUPEB, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Aline Rezende Abreu
- Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, MG, Brazil; Graduate Program in Biological Sciences CBIOL/NUPEB, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Deoclecio Chianca-Jr
- Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, MG, Brazil; Graduate Program in Biological Sciences CBIOL/NUPEB, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Rodrigo Cunha de Menezes
- Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, MG, Brazil; Graduate Program in Biological Sciences CBIOL/NUPEB, Federal University of Ouro Preto, Ouro Preto, Brazil.
| |
Collapse
|
3
|
Moore NLT, Altman DE, Gauchan S, Genovese RF. Adulthood stress responses in rats are variably altered as a factor of adolescent stress exposure. Stress 2016; 19:295-302. [PMID: 27295201 DOI: 10.1080/10253890.2016.1191465] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Stress exposure during development may influence adulthood stress response severity. The present study investigates persisting effects of two adolescent stressors upon adulthood response to predator exposure (PE). Rats were exposed to underwater trauma (UWT) or PE during adolescence, then to PE after reaching adulthood. Rats were then exposed to predator odor (PO) to test responses to predator cues alone. Behavioral and neuroendocrine assessments were conducted to determine acute effects of each stress experience. Adolescent stress altered behavioral response to adulthood PE. Acoustic startle response was blunted. Bidirectional changes in plus maze exploration were revealed as a factor of adolescent stress type. Neuroendocrine response magnitude did not predict severity of adolescent or adult stress response, suggesting that different adolescent stress events may differentially alter developmental outcomes regardless of acute behavioral or neuroendocrine response. We report that exposure to two different stressors in adolescence may differentially affect stress response outcomes in adulthood. Acute response to an adolescent stressor may not be consistent across all stressors or all dependent measures, and may not predict alterations in developmental outcomes pertaining to adulthood stress exposure. Further studies are needed to characterize factors underlying long-term effects of a developmental stressor.
Collapse
Affiliation(s)
- Nicole L T Moore
- a Military Psychiatry Branch , Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research , Silver Spring , MD , USA
| | - Daniel E Altman
- a Military Psychiatry Branch , Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research , Silver Spring , MD , USA
| | - Sangeeta Gauchan
- a Military Psychiatry Branch , Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research , Silver Spring , MD , USA
| | - Raymond F Genovese
- a Military Psychiatry Branch , Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research , Silver Spring , MD , USA
| |
Collapse
|
4
|
Ishii D, Matsuzawa D, Matsuda S, Tomizawa H, Sutoh C, Shimizu E. Methyl donor-deficient diet during development can affect fear and anxiety in adulthood in C57BL/6J mice. PLoS One 2014; 9:e105750. [PMID: 25144567 PMCID: PMC4140817 DOI: 10.1371/journal.pone.0105750] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/28/2014] [Indexed: 01/14/2023] Open
Abstract
DNA methylation is one of the essential factors in the control of gene expression. Folic acid, methionine and choline (methyl donors)--all nutrients related to one-carbon metabolism--are known as important mediators of DNA methylation. A previous study has shown that long-term administration of a diet lacking in methyl donors caused global DNA hypermethylation in the brain (Pogribny et al., 2008). However, no study has investigated the effects of a diet lacking in methyl donors during the developmental period on emotional behaviors such as fear and anxiety-like behavior in association with gene expressions in the brain. In addition, it has not been elucidated whether a diet supplemented with methyl donors later in life can reverse these changes. Therefore, we examined the effects of methyl donor deficiency during the developmental period on fear memory acquisition/extinction and anxiety-like behavior, and the relevant gene expressions in the hippocampus in juvenile (6-wk) and adult (12-wk) mice. We found that juvenile mice fed a methyl-donor-deficient diet had impaired fear memory acquisition along with decreases in the gene expressions of Dnmt3a and Dnmt3b. In addition, reduced anxiety-like behavior with decreased gene expressions of Grin2b and Gabar2 was observed in both the methyl-donor-deficient group and the body-weight-matched food-restriction group. After being fed a diet supplemented with methyl donors ad libitum, adult mice reversed the alteration of gene expression of Dnmt3a, Dnmt3b, Grin2b and Gabar2, but anxiety-like behavior became elevated. In addition, impaired fear-memory formation was observed in the adult mice fed the methyl-donor-deficient diet during the developmental period. Our study suggested that developmental alterations in the one-carbon metabolic pathway in the brain could have effects on emotional behavior and memory formation that last into adulthood.
Collapse
Affiliation(s)
- Daisuke Ishii
- Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Daisuke Matsuzawa
- Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan
- Research Center for Child Mental Development, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Shingo Matsuda
- Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Haruna Tomizawa
- Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Chihiro Sutoh
- Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan
- Research Center for Child Mental Development, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Eiji Shimizu
- Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, Chiba, Japan
- Research Center for Child Mental Development, Graduate School of Medicine, Chiba University, Chiba, Japan
| |
Collapse
|
5
|
Shannonhouse JL, Fong LA, Clossen BL, Hairgrove RE, York DC, Walker BB, Hercules GW, Mertesdorf LM, Patel M, Morgan C. Female-biased anorexia and anxiety in the Syrian hamster. Physiol Behav 2014; 133:141-51. [DOI: 10.1016/j.physbeh.2014.05.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 05/07/2014] [Accepted: 05/16/2014] [Indexed: 01/26/2023]
|
6
|
Shannonhouse JL, York DC, Morgan C. A modified anxious behavior test for hamsters. J Neurosci Methods 2014; 221:62-9. [DOI: 10.1016/j.jneumeth.2013.09.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 09/18/2013] [Accepted: 09/21/2013] [Indexed: 10/26/2022]
|
7
|
Chee SSA, Menard JL. The histaminergic H1, H2, and H3 receptors of the lateral septum differentially mediate the anxiolytic-like effects of histamine on rats' defensive behaviors in the elevated plus maze and novelty-induced suppression of feeding paradigm. Physiol Behav 2013; 116-117:66-74. [DOI: 10.1016/j.physbeh.2013.03.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Revised: 01/29/2013] [Accepted: 03/14/2013] [Indexed: 11/30/2022]
|
8
|
Lopes APF, Ganzer L, Borges AC, Kochenborger L, Januário AC, Faria MS, Marino-Neto J, Paschoalini MA. Effects of GABA ligands injected into the nucleus accumbens shell on fear/anxiety-like and feeding behaviours in food-deprived rats. Pharmacol Biochem Behav 2012; 101:41-8. [DOI: 10.1016/j.pbb.2011.11.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 10/24/2011] [Accepted: 11/15/2011] [Indexed: 10/15/2022]
|
9
|
Rodriguez-Porcel F, Green D, Khatri N, Harris SS, May WL, Lin RCS, Paul IA. Neonatal exposure of rats to antidepressants affects behavioral reactions to novelty and social interactions in a manner analogous to autistic spectrum disorders. Anat Rec (Hoboken) 2011; 294:1726-35. [PMID: 21905242 DOI: 10.1002/ar.21402] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 03/09/2011] [Accepted: 03/10/2011] [Indexed: 11/11/2022]
Abstract
We have demonstrated that neonatal exposure to selective serotonin reuptake inhibitors has lasting effects on behavior and serotonergic neurons in Long Evans rats. Hyperserotoninemia and altered sensory processing are reported in autistic spectrum disorders (ASD). We hypothesized that early life exposure to SSRIs alters sensory processing, disrupts responses to novelty, and impairs social interactions in a manner similar to that observed in ASD. Male and female Long-Evans rat pups were administered citalopram, buproprion, fluoxetine, or saline from postnatal day (P) 8-21. Rats were tested for response to a novel tone before weaning (P25). Later, rats were tested 2× for response to a novel object (P39), and to a novel conspecific (P78, P101). In addition, rats were assessed for juvenile play behaviors (P32-P34) and later, we assessed sexual response to an estrus female in male rats (P153-184). Antidepressant exposure increased freezing after tone, diminished novel object exploration, and reduced conspecific interaction up to 3× compared to saline exposed rats. Juvenile play was profoundly reduced in antidepressant-exposed males when compared to saline exposed groups. Exposure to the SSRIs, but not bupropion disrupted male sexual behaviors. Moreover, specific male responses to female proceptive behaviors were disrupted in SSRI, but not bupropion exposed rats. We conclude that neonatal exposure to antidepressants in rats results in sensory and social abnormalities that parallel many of those reported in ASD.
Collapse
Affiliation(s)
- Federico Rodriguez-Porcel
- Department of Psychiatry & Human Behavior, University of Mississippi Medical Center, Jackson, 39216-4505, USA
| | | | | | | | | | | | | |
Collapse
|
10
|
Kochenborger L, Zanatta D, Berretta LM, Lopes APF, Wunderlich BL, Januário AC, Neto JM, Terenzi MG, Paschoalini MA, Faria MS. Modulation of fear/anxiety responses, but not food intake, following α-adrenoceptor agonist microinjections in the nucleus accumbens shell of free-feeding rats. Neuropharmacology 2011; 62:427-35. [PMID: 21871465 DOI: 10.1016/j.neuropharm.2011.08.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 08/10/2011] [Accepted: 08/11/2011] [Indexed: 10/17/2022]
Abstract
This study investigated the effect of α-adrenoceptor agonists microinjected into the shell region of the accumbens nucleus (AcbSh) on feeding and anxiety-related behaviors in free-feeding rats. Male Wistar rats with a chronically implanted cannula into the AcbSh were unilaterally microinjected with either clonidine (CLON, α(2)-adrenoceptor agonist) or phenylephrine (PHEN, α(1)-adrenoceptor agonist) at the doses of 6 and 20 nmol and submitted to the elevated plus-maze (EPM), a pre-clinical test of anxiety. Immediately after the EPM test, the animals underwent food intake evaluation for 30 min. The data showed that rats microinjected with CLON (20 nmol/0.2 μl) into the AcbSh exhibited increased %Open arm time, which is compatible with an anxiolytic-like effect. The CLON-induced anxiolysis was corroborated by increased head-dipping and decreased stretched-attend posture, two ethologically derived behaviors which are fear/anxiety-motivated. The animal's locomotor activity was not changed by 20 nmol CLON microinjection into the AcbSh. However, neither dose of PHEN microinjected into the AcbSh was able to alter either the spatial-temporal or ethological variables representative of fear/anxiety and locomotion. Food intake was not altered by any dose of CLON and PHEN microinjected into the AcbSh, but the 20 nmol CLON microinjection induced increased motor activity in the feeding test. The data suggests that noradrenergic projections to the AcbSh may underlie fear/anxiety modulation through α(2)-adrenoceptor in the AcbSh, while feeding behavior was unaffected by noradrenergic modulation in the AcbSh of free-feeding rats. This article is part of a Special Issue entitled 'Anxiety and Depression'.
Collapse
Affiliation(s)
- Larissa Kochenborger
- Department of Physiological Sciences, Centre of Biological Sciences, Federal University of Santa Catarina (UFSC), 88040-900 Florianópolis, SC, Brazil.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Trent NL, Menard JL. Infusions of neuropeptide Y into the lateral septum reduce anxiety-related behaviors in the rat. Pharmacol Biochem Behav 2011; 99:580-90. [PMID: 21693128 DOI: 10.1016/j.pbb.2011.06.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 05/23/2011] [Accepted: 06/06/2011] [Indexed: 11/24/2022]
Abstract
Neuropeptide Y (NPY) is one of the most abundant peptides in mammalian brain and NPY-like-immunoreactivity is highly expressed in the lateral septum, an area extensively involved in anxiety regulation. NPY counteracts the neurochemical and behavioral responses to acute threat in animal models, and intracerebroventricular (i.c.v.) administration of NPY at low doses is anxiolytic. Less is known about the specific contributions of the lateral septum to NPY-mediated anxiety regulation. In Experiment 1, the effects of infusions of NPY (1.5 μg) into the lateral septum were investigated in three animal models of anxiety: the elevated plus-maze, novelty-induced suppression of feeding, and shock-probe burying tests. Experiment 2 examined the role of the NPY Y1 receptor in these models by co-infusing the Y1 antagonist BIBO 3304 (0.15 μg, 0.30 μg) with NPY into the lateral septum. In the elevated plus-maze, there were no changes in rats' open arm exploration, the index of anxiety reduction in this test. In the novelty-induced suppression of feeding test, rats infused with NPY showed decreases in the latency to consume a palatable snack in a novel (but not familiar) environment, suggesting a reduction in anxiety independent of increases in appetite. This anxiolysis was attenuated by co-infusion with BIBO 3304 (0.30 μg) in Experiment 2. Lastly, rats infused with NPY showed decreases in the duration of burying behavior in the shock-probe burying test, also indicative of anxiety reduction. However, unlike in the feeding test, BIBO 3304 did not attenuate the NPY-induced anxiolysis in the shock-probe test. It is concluded that NPY produces anxiolytic-like actions in the lateral septum in two animal models of anxiety: the novelty-induced suppression of feeding, and shock-probe burying tests, and that this anxiolysis is dependent on Y1 receptor activation in the feeding test.
Collapse
Affiliation(s)
- Natalie L Trent
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
| | | |
Collapse
|
12
|
Chee SSA, Menard JL. Lesions of the dorsal lateral septum do not affect neophagia in the novelty induced suppression of feeding paradigm but reduce defensive behaviours in the elevated plus maze and shock probe burying tests. Behav Brain Res 2011; 220:362-6. [PMID: 21356249 DOI: 10.1016/j.bbr.2011.02.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 02/12/2011] [Accepted: 02/21/2011] [Indexed: 10/18/2022]
Abstract
Past studies have shown that the lateral septum is involved in anxiety. Here, we tested whether the dorsal lateral septum contributes to neophagia by using the novelty induced suppression of feeding (NISF) paradigm. We found that while lesions of the dorsal lateral septum did not affect home or novel cage responding in the NISF test, they did decrease open arm avoidance in the elevated plus maze and burying in the shock probe burying test. Our results suggest that the dorsal lateral septum does not regulate neophagia in the NISF, but further experiments are needed to determine if the same is true for the intermediate and ventral lateral septum.
Collapse
Affiliation(s)
- San-San A Chee
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
| | | |
Collapse
|
13
|
Roberge MC, Hotte-Bernard J, Messier C, Plamondon H. Food restriction attenuates ischemia-induced spatial learning and memory deficits despite extensive CA1 ischemic injury. Behav Brain Res 2007; 187:123-32. [PMID: 17949826 DOI: 10.1016/j.bbr.2007.09.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2007] [Revised: 08/27/2007] [Accepted: 09/01/2007] [Indexed: 01/14/2023]
Abstract
The purpose of the present study was to examine whether short-term food restriction (40% less food over a 3-month period) can attenuate ischemia-induced CA1 neuronal degeneration, and whether this attenuation translated into improved recovery of functional impairments following global ischemia. There was a significant loss of pyramidal CA1 neurons in ischemic compared to sham-operated rats but no difference between the ad lib and food-restricted ischemic animals. Although the diet did not influence neuronal damage in ischemic animals, the performance of food-restricted ischemic rats in spatial task such as the radial arm maze was significantly better than that of ad lib fed ischemic rats. Food-restricted ischemic rats made equivalent numbers of working memory errors as sham-operated animals and took the same time to complete a standard 8-arm radial arm maze task. They also displayed higher activity level in the open field compared to ad libitum fed ischemic rats, and spent considerably more time in the open arms of the elevated plus maze compared to the other groups, suggesting decreased anxiety in these ischemic rats. The relative sparing of spatial memory performance in food-restricted ischemic animals suggests that food restriction facilitates functional recovery.
Collapse
|
14
|
Park MK, Belluzzi JD, Han SH, Cao J, Leslie FM. Age, sex and early environment contribute to individual differences in nicotine/acetaldehyde-induced behavioral and endocrine responses in rats. Pharmacol Biochem Behav 2006; 86:297-305. [PMID: 17141304 DOI: 10.1016/j.pbb.2006.10.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Revised: 08/01/2006] [Accepted: 10/03/2006] [Indexed: 11/19/2022]
Abstract
Neonatal handling was used to evaluate the influence of early environment on responses to nicotine. Rats exposed as pups to daily short-term separation from the dam (H) were compared to non-handled (NH) controls. In experiment 1, prepubescent males and females, aged postnatal day (P) 30, were tested for the effect of nicotine/acetaldehyde (NicAc) on open field behavior and plasma corticosterone levels. NicAc induced increases in ambulatory activity and time spent in the center of the field in NH, but not H, males. Drug-induced increases in initial ambulatory activity, but not center time, were also seen in NH and H females. Handling, but not sex, contributed to group differences in plasma corticosterone levels. In experiment 2, NH and H rats were tested for acquisition of NicAc self-administration at three ages, P27-31, P34-38 and P90-94. Age and sex, but not handling, contributed to differences in performance of this task. Whereas males exhibited a decrease in responding with age, females did not. These findings demonstrate that neonatal handling may serve as an experimental model for individual differences in sensitivity to tobacco constituents. Furthermore, the current study indicates that stress reactivity, age and sex may play differential roles in initiating smoking behavior.
Collapse
Affiliation(s)
- Minjung K Park
- Department of Pharmacology, School of Medicine, University of California, Irvine, California 92697, USA
| | | | | | | | | |
Collapse
|
15
|
Martín-García E, Pallarès M. The neurosteroid pregnenolone sulfate neutralized the learning impairment induced by intrahippocampal nicotine in alcohol-drinking rats. Neuroscience 2005; 136:1109-19. [PMID: 16203107 DOI: 10.1016/j.neuroscience.2005.08.036] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2005] [Revised: 04/01/2005] [Accepted: 08/15/2005] [Indexed: 01/06/2023]
Abstract
The effects of intrahippocampal administration of nicotine and the neurosteroids pregnenolone sulfate and allopregnanolone on acquiring the lever-press response and extinction in a Skinner box were examined using voluntary alcohol-drinking rats. A free-choice drinking procedure that implies early availability of the alcoholic solution (10% ethanol v/v+3% glucose w/v in distilled water) was used. Alcohol and control rats were deprived of food and assigned at random to six groups. Each group received two consecutive intrahippocampal (dorsal CA1) injections immediately after 1-h of drinking ethanol and before the free lever-press response shaping and extinction session. The groups were: saline-saline; saline-pregnenolone sulfate (5 ng, 24 microM); saline-allopregnanolone (0.2 microg, 1.26 microM); nicotine (4.6 microg, 20 mM)-saline; nicotine-pregnenolone sulfate; nicotine-allopregnanolone. Blood alcohol concentrations were assessed the day before conditioning. The combination of the oral self-administration of ethanol and the intrahippocampal injection of nicotine deteriorated the ability to acquire the lever-press response. This effect was neutralized by intrahippocampal pregnenolone sulfate (negative modulator of the GABA(A) receptor complex), and it was not affected by intrahippocampal allopregnanolone (positive GABA receptor complex A modulator). Pregnenolone sulfate and allopregnanolone had no effects per se on lever-press acquisition, neither in alcohol-drinking rats nor in controls. Alcohol consumption facilitated operant extinction just as anxiolytics that act as positive modulators of the GABA receptor complex A receptors do, possibly reducing the anxiety or aversion related to non-reinforcement. This effect was increased by intrahippocampal nicotine.
Collapse
Affiliation(s)
- E Martín-García
- Institut de Neurociències, Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | | |
Collapse
|
16
|
Trimmel M, Wittberger S. Effects of transdermally administered nicotine on aspects of attention, task load, and mood in women and men. Pharmacol Biochem Behav 2004; 78:639-45. [PMID: 15251273 DOI: 10.1016/j.pbb.2004.04.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Revised: 04/09/2004] [Accepted: 04/29/2004] [Indexed: 11/27/2022]
Abstract
This double-blind placebo-controlled study was conducted to determine nicotine effects on diverse types of attentional performance, task load, and mood considering sex effects as suggested by animal studies. Twelve smokers, 12 deprived smokers and 12 nonsmokers (6 females, 6 males in each group) were investigated. Participants were treated either by 5 mg/16 h nicotine patches (Nicorette) or placebo. Effects of treatment were examined by a computerized attention-test battery; mood was assessed by the Berliner-Alltagssprachliches-Stimmungs-Inventar and task load by the NASA Task Load Index (NASA-TLX). Results showed that nicotine significantly increased the number of hits and decreased reaction time (RT) in the vigilance task. In the selective attention task combined with irrelevant speech as background noise, nicotine enhanced rate of hits. Although it was indicated that nicotine leads to a generally higher accuracy in attention tasks, response time of visual search was prolonged, contradicting a universal facilitation by nicotine. Participants experienced mental demand and temporal demand lower and rated alertness higher when in the nicotine condition. These effects were independent of smoking status, indicating "true" nicotine effects. Females took significant advantage of nicotine in the vigilance task, reaching the performance level of males, accompanied by a higher rated alertness. Results indicate task- and sex-dependent nicotine effects.
Collapse
Affiliation(s)
- Michael Trimmel
- Medical University of Vienna, Institute of Environmental Health, Kinderspitalgasse 15, A-1095 Vienna, Austria.
| | | |
Collapse
|
17
|
Inoue K, Zorrilla EP, Tabarin A, Valdez GR, Iwasaki S, Kiriike N, Koob GF. Reduction of anxiety after restricted feeding in the rat: implication for eating disorders. Biol Psychiatry 2004; 55:1075-81. [PMID: 15158426 DOI: 10.1016/j.biopsych.2004.01.026] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2003] [Revised: 01/15/2004] [Accepted: 01/25/2004] [Indexed: 10/26/2022]
Abstract
BACKGROUND Eating-disorder patients exhibit not only abnormal eating attitudes but also pathologic anxiety-like behaviors. The specific nature of the relationship between dieting and anxiety-like behavior is unknown. METHODS To investigate the adaptational changes that resulted from chronic restricted scheduled feeding (2-hour access per day for 2 weeks) and subsequent free refeeding, longitudinal changes in the microstructure of feeding behavior were studied in male rats. To study the relationship between restricted feeding and anxiety-like behavior, separate rats were tested in the elevated plus-maze under the following conditions: 1) free feeding; 2) acute food restriction (2-hour access for 1 day); 3) chronic food restriction (for 10 days); or 4) postrecovery (after 10 days of free feeding subsequent to chronic food restriction). RESULTS The effects of chronic food restriction on meal structure diminished within a few days after refeeding. Decreased anxiety-like behavior was seen during acute and chronic food restriction and did not reflect nonspecific behavioral activation. Anxiolytic-like effects persisted after 10 days of refeeding. CONCLUSIONS Chronic food restriction produced reductions in anxiety-like behavior that persisted beyond the normalization of food intake patterns. The findings might have etiologic and pathophysiologic relevance for the restrained eating pattern in eating-disorder patients with comorbid anxious symptoms.
Collapse
Affiliation(s)
- Koki Inoue
- Department of Neuropharmacology, The Scripps Research Institute, La Jolla, California, USA
| | | | | | | | | | | | | |
Collapse
|