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Kim MH, Park J, Han DH, Noh JY, Ji ES, Lee SH, Kim CJ, Cho S. Alternating mealtimes during pregnancy and weaning triggers behavioral changes in adult offspring. Reproduction 2023; 165:135-146. [PMID: 36322471 DOI: 10.1530/rep-22-0164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022]
Abstract
In brief Mealtime changes in pregnant mice revealed impaired neurobehavioral development in mouse offspring. This study is the basis for investigating diseases associated with neurobehavioral development of adult offspring of pregnant shift-working women. Abstract Most organisms on Earth have a biological clock, and their physiological processes are regulated by a 1-day cycle. In modern society, several factors can disturb these biological clocks in humans; in particular, individuals working in shifts are exposed to stark environmental changes that interfere with their biological clock. They have a high risk of various diseases. However, there are scarce experimental approaches to address the reproductive and health consequences of shift work in the offspring of exposed individuals. In this study, considering the fact that shift workers usually have their meals during their adjusted working time, we aimed to examine the effects of a 12-h shift with usual mealtime as a plausible night work model on the neurobehavioral development of adult mouse offspring. In these offspring, early exposure to this mealtime shift differentially affected circadian rhythmic variables and total locomotor activity depending on the timing and duration of restrictive feeding. Moreover, neurobehavioral alterations such as declined short-term memory and depressive-like behavior were observed in adulthood. These results have implications for the health concerns of shift-working women and their children.
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Affiliation(s)
- Mi-Hee Kim
- Department of Neuroscience, Graduate school, Kyung Hee University, Seoul, Korea
| | - Jihyun Park
- Department of Neuroscience, Graduate school, Kyung Hee University, Seoul, Korea
| | - Dong-Hee Han
- Department of Neuroscience, Graduate school, Kyung Hee University, Seoul, Korea
| | - Jong-Yun Noh
- Department of Neuroscience, Graduate school, Kyung Hee University, Seoul, Korea
| | - Eun-Sang Ji
- Department of Sport & Health Science, College of Natural Science, Sangmyung University, Seoul, Korea
| | - Sung-Ho Lee
- Department of Life Science, Sangmyung University, Seoul, Korea
| | - Chang-Ju Kim
- Department of Physiology, Kyung Hee University School of Medicine, Seoul, Korea
| | - Sehyung Cho
- Department of Neuroscience, Graduate school, Kyung Hee University, Seoul, Korea.,Department of Physiology, Kyung Hee University School of Medicine, Seoul, Korea
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Stowe TA, McClung CA. How Does Chronobiology Contribute to the Development of Diseases in Later Life. Clin Interv Aging 2023; 18:655-666. [PMID: 37101656 PMCID: PMC10124625 DOI: 10.2147/cia.s380436] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 04/13/2023] [Indexed: 04/28/2023] Open
Abstract
An increasingly older population is one of the major social and medical challenges we currently face. Between 2010 and 2050, it is estimated that the proportion of adults over 65 years of age will double from 8% to 16% of the global population. A major concern associated with aging is the changes in health that can lead to various diseases such as cancer and neurogenerative diseases, which are major burdens on individuals and societies. Thus, it is imperative to better understand changes in sleep and circadian rhythms that accompany aging to improve the health of an older population and target diseases associated with aging. Circadian rhythms play a role in most physiological processes and can contribute to age-related diseases. Interestingly, there is a relationship between circadian rhythms and aging. For example, many older adults have a shift in chronotype, which is an individual's natural inclination to sleep certain times of the day. As adults age, most people tend to go to sleep earlier while also waking up earlier. Numerous studies also suggest that disrupted circadian rhythms may be indicative of developing age-related diseases, like neurodegenerative disorders and cancer. Better understanding the relationship between circadian rhythms and aging may allow us to improve current treatments or develop novel ones that target diseases commonly associated with aging.
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Affiliation(s)
- Taylor A Stowe
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Colleen A McClung
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
- Correspondence: Colleen A McClung, Email
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Robinson-Junker A, O’Hara B, Durkes A, Gaskill B. Sleeping through anything: The effects of unpredictable disruptions on mouse sleep, healing, and affect. PLoS One 2019; 14:e0210620. [PMID: 30703113 PMCID: PMC6354982 DOI: 10.1371/journal.pone.0210620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 12/29/2018] [Indexed: 01/27/2023] Open
Abstract
Many aspects of the laboratory environment are not tailored to the needs of rodents, which may cause stress. Unpredictable stressors can cause ulcers, prolonged pituitary-adrenal activation, and anhedonia. Similarly, pain has been demonstrated to slow wound healing, and mice experiencing pain exhibit altered behavior. However it is unknown how husbandry, which occurs when the mice are inactive, and lack of analgesia, specifically in a punch biopsy procedure, effects animal physiology, behavior, and welfare, particularly as it relates to sleep fragmentation. We hypothesized that sleep fragmentation, induced by unpredictable husbandry and lack of pain management will slow wound healing. Two main treatments were tested in a factorial design in C57BL/6 mice of both sexes (64 mice total); 1) analgesia (carprofen and saline) and 2) sleep disruptions (random and predictable). Mice were singly housed in a non-invasive sleep monitoring apparatus on arrival (Day -4). Disruption treatments were applied from Day -3 to 2. All mice received a punch biopsy surgery (Day 0) with topical lidocaine gel and their analgesic treatment prior to recovery, and on Days 1 and 2. Nesting behavior was assessed daily and a sugar cereal consumption test, as a measure of anhedonia, was conducted on Days -1 to 2. On Day 3, mice were euthanized and wound tissue and adrenal glands were collected. We found that the disruption predictability had no effect on mouse sleep, wound healing, or adrenal cortex:medulla ratio. It's possible that the disruption period was not long enough to induce chronic stress. However, male mice who received analgesia slept more than their female counterparts; this may be related to sex differences in pain perception. Overall, it does not appear that the predictability of disturbance effects sleep fragmentation or stress responses, indicating that husbandry activities do not need to occur at set predictable times to improve welfare.
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Affiliation(s)
- Amy Robinson-Junker
- Department of Comparative Pathobiology, School of Veterinary Medicine, Purdue University, West Lafayette, Indiana, United States of America
| | - Bruce O’Hara
- Department of Biology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Abigail Durkes
- Department of Comparative Pathobiology, School of Veterinary Medicine, Purdue University, West Lafayette, Indiana, United States of America
| | - Brianna Gaskill
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana, United States of America
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Ruby CL, Palmer KN, Zhang J, Risinger MO, Butkowski MA, Swartzwelder HS. Differential Sensitivity to Ethanol-Induced Circadian Rhythm Disruption in Adolescent and Adult Mice. Alcohol Clin Exp Res 2016; 41:187-196. [PMID: 27997028 DOI: 10.1111/acer.13275] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/19/2016] [Indexed: 12/29/2022]
Abstract
BACKGROUND Growing evidence supports a central role for the circadian system in alcohol use disorders, but few studies have examined this relationship during adolescence. In mammals, circadian rhythms are regulated by the suprachiasmatic nucleus, a biological clock whose timing is synchronized (reset) to the environment primarily by light (photic) input. Alcohol (ethanol [EtOH]) disrupts circadian timing in part by attenuating photic phase-resetting responses in adult rodents. However, circadian rhythms change throughout life and it is not yet known whether EtOH has similar effects on circadian regulation during adolescence. METHODS General circadian locomotor activity was monitored in male C57BL6/J mice beginning in adolescence (P27) or adulthood (P61) in a 12-hour light, 12-hour dark photocycle for ~2 weeks to establish baseline circadian activity measures. On the day of the experiment, mice received an acute injection of EtOH (1.5 g/kg, i.p.) or equal volume saline 15 minutes prior to a 30-minute light pulse at Zeitgeber Time 14 (2 hours into the dark phase) and then were released into constant darkness (DD) for ~2 weeks to assess phase-resetting responses. Control mice of each age-group received injections but no light pulse prior to DD. RESULTS While adults showed the expected decrease in photic phase-delays induced by acute EtOH, this effect was absent in adolescent mice. Adolescents also showed baseline differences in circadian rhythmicity compared to adults, including advanced photocycle entrainment, larger photic phase-delays, a shorter free-running (endogenous) circadian period, and greater circadian rhythm amplitude. CONCLUSIONS Collectively, our results indicate that adolescent mice are less sensitive to the effect of EtOH on circadian photic phase-resetting and that their daily activity rhythms are markedly different than those of adults.
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Affiliation(s)
- Christina L Ruby
- Department of Biology, Indiana University of Pennsylvania, Indiana, Pennsylvania
| | - Kaitlyn N Palmer
- Department of Biology, Indiana University of Pennsylvania, Indiana, Pennsylvania
| | - Jiawen Zhang
- Department of Biology, Indiana University of Pennsylvania, Indiana, Pennsylvania
| | - Megan O Risinger
- Department of Biology, Indiana University of Pennsylvania, Indiana, Pennsylvania
| | - Melissa A Butkowski
- Department of Biology, Indiana University of Pennsylvania, Indiana, Pennsylvania
| | - H Scott Swartzwelder
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, North Carolina.,Neurobiology Research Laboratory, VA Medical Center, Durham, North Carolina
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Rocha LSD, de Matos RJB, de Souza JA, Costa ACO, Lopes de Souza S, Muniz GDS, Nascimento ED. Daytime increase in caloric intake without change in total 24-h caloric intake can increase adiposity but not total bodyweight in rats with inverted feeding pattern. Appl Physiol Nutr Metab 2016; 42:931-940. [PMID: 28511018 DOI: 10.1139/apnm-2016-0536] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The goal of this study was to evaluate the effect of the food availability period on body weight, self-selection of macronutrients, adiposity, lipoprotein, and serum glucose profiles without changing energy intake. Young male rats were divided into 2 groups according to the availability of food during the light and dark phases of the cycle, forming 2 groups: control group (CG) and group with inverted feeding pattern (IFPG). Before inversion of food availability on the 80th day, circadian food intake was measured every 4 h over 24 h during 3 days. The glycemic curve, an oral test for glucose tolerance, and self-selection of macronutrients were evaluated. Blood samples were collected for analysis of fasting glucose, triglycerides, and total cholesterol fractions. The IFPG showed an increase in fasting glucose in the dark phase of the cycle, changes in the glycemic curve, and oral glucose tolerance test. It also showed increased abdominal and liver fat and distinct choice of macronutrients compared with the CG. A change in the availability of food according to the phase of the circadian cycle produces changes in glucose and feeding circadian rhythm culminating in increased abdominal and hepatic fat. These effects can increase the risk of metabolic disorders and installation of chronic diseases.
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Abril-Gil M, Garcia-Just A, Pérez-Cano FJ, Franch À, Castell M. Development and characterization of an effective food allergy model in Brown Norway rats. PLoS One 2015; 10:e0125314. [PMID: 25923134 PMCID: PMC4414460 DOI: 10.1371/journal.pone.0125314] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 03/17/2015] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Food allergy (FA) is an adverse health effect produced by the exposure to a given food. Currently, there is no optimal animal model of FA for the screening of immunotherapies or for testing the allergenicity of new foods. OBJECTIVE The aim of the present study was to develop an effective and rapid model of FA in Brown Norway rats. In order to establish biomarkers of FA in rat, we compared the immune response and the anaphylactic shock obtained in this model with those achieved with only intraperitoneal immunization. METHODS Rats received an intraperitoneal injection of ovalbumin (OVA) with alum and toxin from Bordetella pertussis, and 14 days later, OVA by oral route daily for three weeks (FA group). A group of rats receiving only the i.p. injection (IP group) were also tested. Serum anti-OVA IgE, IgG1, IgG2a, IgG2b and IgA antibodies were quantified throughout the study. After an oral challenge, body temperature, intestinal permeability, motor activity, and mast cell protease II (RMCP-II) levels were determined. At the end of the study, anti-OVA intestinal IgA, spleen cytokine production, lymphocyte composition of Peyer's patches and mesenteric lymph nodes, and gene expression in the small intestine were quantified. RESULTS Serum OVA-specific IgG1, IgG2a and IgG2b concentrations rose with the i.p. immunization but were highly augmented after the oral OVA administration. Anti-OVA IgE increased twofold during the first week of oral OVA gavage. The anaphylaxis in both IP and FA groups decreased body temperature and motor activity, whereas intestinal permeability increased. Interestingly, the FA group showed a much higher RMCP II serum protein and intestinal mRNA expression. CONCLUSIONS These results show both an effective and relatively rapid model of FA assessed by means of specific antibody titres and the high production of RMCP-II and its intestinal gene expression.
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Affiliation(s)
- Mar Abril-Gil
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Recerca en Nutrició i Seguretat Alimentària, Universitat de Barcelona (INSA-UB), Barcelona, Spain
| | - Alba Garcia-Just
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Recerca en Nutrició i Seguretat Alimentària, Universitat de Barcelona (INSA-UB), Barcelona, Spain
| | - Francisco J. Pérez-Cano
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Recerca en Nutrició i Seguretat Alimentària, Universitat de Barcelona (INSA-UB), Barcelona, Spain
| | - Àngels Franch
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Recerca en Nutrició i Seguretat Alimentària, Universitat de Barcelona (INSA-UB), Barcelona, Spain
| | - Margarida Castell
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Institut de Recerca en Nutrició i Seguretat Alimentària, Universitat de Barcelona (INSA-UB), Barcelona, Spain
- * E-mail:
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Herrero L, Valcarcel L, da Silva CA, Albert N, Diez-Noguera A, Cambras T, Serra D. Altered circadian rhythm and metabolic gene profile in rats subjected to advanced light phase shifts. PLoS One 2015; 10:e0122570. [PMID: 25837425 PMCID: PMC4383616 DOI: 10.1371/journal.pone.0122570] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/16/2015] [Indexed: 01/02/2023] Open
Abstract
The circadian clock regulates metabolic homeostasis and its disruption predisposes to obesity and other metabolic diseases. However, the effect of phase shifts on metabolism is not completely understood. We examined whether alterations in the circadian rhythm caused by phase shifts induce metabolic changes in crucial genes that would predispose to obesity. Three-month-old rats were maintained on a standard diet under lighting conditions with chronic phase shifts consisting of advances, delays or advances plus delays. Serum leptin, insulin and glucose levels decreased only in rats subjected to advances. The expression of the clock gene Bmal 1 increased in the hypothalamus, white adipose tissue (WAT), brown adipose tissue (BAT) and liver of the advanced group compared to control rats. The advanced group showed an increase in hypothalamic AgRP and NPY mRNA, and their lipid metabolism gene profile was altered in liver, WAT and BAT. WAT showed an increase in inflammation and ER stress and brown adipocytes suffered a brown-to-white transformation and decreased UCP-1 expression. Our results indicate that chronic phase advances lead to significant changes in neuropeptides, lipid metabolism, inflammation and ER stress gene profile in metabolically relevant tissues such as the hypothalamus, liver, WAT and BAT. This highlights a link between alteration of the circadian rhythm and metabolism at the transcriptional level.
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Affiliation(s)
- Laura Herrero
- Department of Biochemistry and Molecular Biology, Facultat de Farmàcia, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Lorea Valcarcel
- Department of Biochemistry and Molecular Biology, Facultat de Farmàcia, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Crhistiane Andressa da Silva
- Department of Physiology, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Laboratório de Neurobiologia e Ritimicidade Biológica, Departamento de Fisiologia, Universidade Federal do Rio Grande do Norte, Natal, Brasil
| | - Nerea Albert
- Department of Physiology, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| | - Antoni Diez-Noguera
- Department of Physiology, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| | - Trinitat Cambras
- Department of Physiology, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- * E-mail: (DS); (TC)
| | - Dolors Serra
- Department of Biochemistry and Molecular Biology, Facultat de Farmàcia, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
- * E-mail: (DS); (TC)
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Abril-Gil M, Garcia-Just A, Cambras T, Pérez-Cano FJ, Castellote C, Franch À, Castell M. Motor activity as an unbiased variable to assess anaphylaxis in allergic rats. Exp Biol Med (Maywood) 2015; 240:1373-7. [PMID: 25716015 DOI: 10.1177/1535370215573393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 12/30/2014] [Indexed: 11/15/2022] Open
Abstract
The release of mediators by mast cells triggers allergic symptoms involving various physiological systems and, in the most severe cases, the development of anaphylactic shock compromising mainly the nervous and cardiovascular systems. We aimed to establish variables to objectively study the anaphylactic response (AR) after an oral challenge in an allergy model. Brown Norway rats were immunized by intraperitoneal injection of ovalbumin with alum and toxin from Bordetella pertussis. Specific immunoglobulin (Ig) E antibodies were developed in immunized animals. Forty days after immunization, the rats were orally challenged with the allergen, and motor activity, body temperature and serum mast cell protease concentration were determined. The anaphylaxis induced a reduction in body temperature and a decrease in the number of animal movements, which was inversely correlated with serum mast cell protease release. In summary, motor activity is a reliable tool for assessing AR and also an unbiased method for screening new anti-allergic drugs.
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Affiliation(s)
- Mar Abril-Gil
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain
| | - Alba Garcia-Just
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain
| | - Trinitat Cambras
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain
| | - Francisco J Pérez-Cano
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain Institut de Recerca en Nutrició i Seguretat Alimentària (INSA-UB), E-08028 Barcelona, Spain
| | - Cristina Castellote
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain Institut de Recerca en Nutrició i Seguretat Alimentària (INSA-UB), E-08028 Barcelona, Spain
| | - Àngels Franch
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain Institut de Recerca en Nutrició i Seguretat Alimentària (INSA-UB), E-08028 Barcelona, Spain
| | - Margarida Castell
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain Institut de Recerca en Nutrició i Seguretat Alimentària (INSA-UB), E-08028 Barcelona, Spain
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Yetnikoff L, Reichard RA, Schwartz ZM, Parsely KP, Zahm DS. Protracted maturation of forebrain afferent connections of the ventral tegmental area in the rat. J Comp Neurol 2014; 522:1031-47. [PMID: 23983069 PMCID: PMC4217282 DOI: 10.1002/cne.23459] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/30/2013] [Accepted: 08/14/2013] [Indexed: 01/21/2023]
Abstract
The mesocorticolimbic dopamine system has long attracted the interest of researchers concerned with the unique gamut of behavioral and mental health vulnerabilities associated with adolescence. Accordingly, the development of the mesocorticolimbic system has been studied extensively, but almost exclusively with regard to dopaminergic output, particularly in the nucleus accumbens and medial prefrontal cortex. To the contrary, the ontogeny of inputs to the ventral tegmental area (VTA), the source of mesocorticolimbic dopamine, has been neglected. This is not a trivial oversight, as the activity of VTA neurons, which reflects their capacity to transmit information about salient events, is sensitively modulated by inputs. Here, we assessed the development of VTA afferent connections using the β subunit of cholera toxin (Ctβ) as a retrograde axonal tracer in adolescent (postnatal day 39) and early adult (8-9-week-old) rats. After intra-VTA injections of Ctβ, adolescent and early adult animals exhibited qualitatively similar distributions of retrogradely labeled neurons in the sense that VTA-projecting neurons were present at all of the same rostrocaudal levels in all of the same structures in both age groups. However, quantitation of retrogradely labeled neurons revealed that adolescent brains, compared with early adult brains, had significantly fewer VTA-projecting neurons preferentially within an interconnected network of cortical and striatopallidal forebrain structures. These findings provide a novel perspective on the development of the mesocorticolimbic dopamine system and may have important implications for age-dependent specificity in the function of this system, particularly with regard to adolescent impulsivity and mental health vulnerabilities.
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Affiliation(s)
- Leora Yetnikoff
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Rhett A. Reichard
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Zachary M. Schwartz
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Kenneth P. Parsely
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Daniel S. Zahm
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
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