메뉴 건너뛰기




Volumn 121, Issue 2, 2007, Pages 401-410

Intracerebroventricular Ethanol-Induced Conditioned Place Preferences Are Prevented by Fluphenazine Infusions Into the Nucleus Accumbens of Rats

Author keywords

dopamine receptor antagonism; drug reward; ethanol; heroin; nucleus accumbens shell

Indexed keywords

ALCOHOL; DIAMORPHINE; DOPAMINE RECEPTOR BLOCKING AGENT; FLUPHENAZINE; CENTRAL DEPRESSANT AGENT; DRUGS USED IN THE TREATMENT OF ADDICTION; NARCOTIC AGENT;

EID: 34249683744     PISSN: 07357044     EISSN: None     Source Type: Journal    
DOI: 10.1037/0735-7044.121.2.401     Document Type: Article
Times cited : (30)

References (65)
  • 1
    • 0035667338 scopus 로고    scopus 로고
    • Differential effects of dopamine antagonists on locomotor activity, conditioned activity and conditioned place preference induced by cocaine in rats
    • Adams J.U., Careri J.M., Efferen T.R., and Rotrosen J. Differential effects of dopamine antagonists on locomotor activity, conditioned activity and conditioned place preference induced by cocaine in rats. Behavioural Pharmacology 12 (2001) 603-611
    • (2001) Behavioural Pharmacology , vol.12 , pp. 603-611
    • Adams, J.U.1    Careri, J.M.2    Efferen, T.R.3    Rotrosen, J.4
  • 4
    • 0026478833 scopus 로고
    • Benzodiazepines and other psychotropic drugs abused by patients in a methadone maintenance program: Familiarity and preference
    • Barnas C., Rossmann M., Roessler H., Riemer Y., and Fleischhacker W.W. Benzodiazepines and other psychotropic drugs abused by patients in a methadone maintenance program: Familiarity and preference. Journal of Clinical Psychopharmacology 12 (1992) 397-402
    • (1992) Journal of Clinical Psychopharmacology , vol.12 , pp. 397-402
    • Barnas, C.1    Rossmann, M.2    Roessler, H.3    Riemer, Y.4    Fleischhacker, W.W.5
  • 5
    • 14044268845 scopus 로고    scopus 로고
    • Ethanol-induced conditioned place preference is expressed through a ventral tegmental area dependent mechanism
    • Bechtholt A.J., and Cunningham C.L. Ethanol-induced conditioned place preference is expressed through a ventral tegmental area dependent mechanism. Behavioral Neuroscience 119 (2005) 213-223
    • (2005) Behavioral Neuroscience , vol.119 , pp. 213-223
    • Bechtholt, A.J.1    Cunningham, C.L.2
  • 6
    • 0032784115 scopus 로고    scopus 로고
    • Peripheral opioid receptors may mediate a portion of the aversive and depressant effect of EtOH: CPP and locomotor activity
    • Bedingfield J.B., King D.A., and Holloway F.A. Peripheral opioid receptors may mediate a portion of the aversive and depressant effect of EtOH: CPP and locomotor activity. Alcohol 18 (1999) 93-101
    • (1999) Alcohol , vol.18 , pp. 93-101
    • Bedingfield, J.B.1    King, D.A.2    Holloway, F.A.3
  • 7
    • 0032423613 scopus 로고    scopus 로고
    • What is the role of dopamine in reward: Hedonic impact, reward learning, or incentive salience?
    • Berridge K.C., and Robinson T.E. What is the role of dopamine in reward: Hedonic impact, reward learning, or incentive salience?. Brain Research Reviews 28 (1998) 309-369
    • (1998) Brain Research Reviews , vol.28 , pp. 309-369
    • Berridge, K.C.1    Robinson, T.E.2
  • 9
    • 0025137874 scopus 로고
    • Evidence for the rewarding effects of ethanol using the conditioned place preference method
    • Bozarth M.A. Evidence for the rewarding effects of ethanol using the conditioned place preference method. Pharmacology Biochemistry and Behavior 35 (1990) 485-487
    • (1990) Pharmacology Biochemistry and Behavior , vol.35 , pp. 485-487
    • Bozarth, M.A.1
  • 11
    • 0036201260 scopus 로고    scopus 로고
    • Factors associated with non-fatal heroin overdose: Assessing the effect of frequency and route of heroin administration
    • Brugal M.T., Barrio G., De L.F., Regidor E., Royuela L., and Suelves J.M. Factors associated with non-fatal heroin overdose: Assessing the effect of frequency and route of heroin administration. Addiction 97 (2002) 319-327
    • (2002) Addiction , vol.97 , pp. 319-327
    • Brugal, M.T.1    Barrio, G.2    De, L.F.3    Regidor, E.4    Royuela, L.5    Suelves, J.M.6
  • 12
    • 0036062627 scopus 로고    scopus 로고
    • Nucleus accumbens cell firing during goal-directed behaviors for cocaine vs. "natural" reinforcement
    • Carelli R.M. Nucleus accumbens cell firing during goal-directed behaviors for cocaine vs. "natural" reinforcement. Physiology and Behavior 76 (2002) 379-387
    • (2002) Physiology and Behavior , vol.76 , pp. 379-387
    • Carelli, R.M.1
  • 13
    • 0000138703 scopus 로고
    • Conditioned place preference as a measure of drug reward
    • Liebman J.M., and Cooper S.J. (Eds), Clarendon Press, Oxford, England
    • Carr G., Fibiger H., and Phillips S. Conditioned place preference as a measure of drug reward. In: Liebman J.M., and Cooper S.J. (Eds). The neuropharmacological basis of reward (1989), Clarendon Press, Oxford, England 264-319
    • (1989) The neuropharmacological basis of reward , pp. 264-319
    • Carr, G.1    Fibiger, H.2    Phillips, S.3
  • 14
    • 0032879092 scopus 로고    scopus 로고
    • Conditioned taste aversion induced by ethanol in alcohol-preferring rats: Influence of the method of ethanol administration
    • Ciccocioppo R., Angeletti S., Chhada M., Perfumi M., Froldi R., and Massi M. Conditioned taste aversion induced by ethanol in alcohol-preferring rats: Influence of the method of ethanol administration. Pharmacology Biochemistry and Behavior 64 (1999) 563-566
    • (1999) Pharmacology Biochemistry and Behavior , vol.64 , pp. 563-566
    • Ciccocioppo, R.1    Angeletti, S.2    Chhada, M.3    Perfumi, M.4    Froldi, R.5    Massi, M.6
  • 15
    • 0036118820 scopus 로고    scopus 로고
    • Low doses of naltrexone reduce palatability and consumption of ethanol in outbred rats
    • Coonfield D.L., Hill K.G., Kaczmarek H.J., Ferraro III F.M., and Kiefer S.W. Low doses of naltrexone reduce palatability and consumption of ethanol in outbred rats. Alcohol 26 (2002) 43-47
    • (2002) Alcohol , vol.26 , pp. 43-47
    • Coonfield, D.L.1    Hill, K.G.2    Kaczmarek, H.J.3    Ferraro III, F.M.4    Kiefer, S.W.5
  • 19
    • 0343933624 scopus 로고
    • Drugs abused by humans preferentially increase synaptic dopamine concentrations in the mesolimbic system of freely moving rats
    • Di Chiara G., and Imperato A. Drugs abused by humans preferentially increase synaptic dopamine concentrations in the mesolimbic system of freely moving rats. Proceedings of the National Academy of Sciences, USA 85 (1988) 5274-5278
    • (1988) Proceedings of the National Academy of Sciences, USA , vol.85 , pp. 5274-5278
    • Di Chiara, G.1    Imperato, A.2
  • 20
    • 0026078121 scopus 로고
    • Haloperidol attenuates conditioned place preferences produced by electrical stimulation of the medial prefrontal cortex
    • Duvauchelle C.L., and Ettenberg A. Haloperidol attenuates conditioned place preferences produced by electrical stimulation of the medial prefrontal cortex. Pharmacology Biochemistry and Behavior 38 (1991) 645-650
    • (1991) Pharmacology Biochemistry and Behavior , vol.38 , pp. 645-650
    • Duvauchelle, C.L.1    Ettenberg, A.2
  • 21
    • 0026534038 scopus 로고
    • Historical factors in the development of ETOH-conditioned place preference
    • Gauvin D.V., and Holloway F.A. Historical factors in the development of ETOH-conditioned place preference. Alcohol 9 (1992) 1-7
    • (1992) Alcohol , vol.9 , pp. 1-7
    • Gauvin, D.V.1    Holloway, F.A.2
  • 22
    • 0022410545 scopus 로고
    • Low doses of ethanol activate dopaminergic neurons in the ventral tegmental area
    • Gessa G.L., Muntoni F., Collu M., Vargiu L., and Mereu G. Low doses of ethanol activate dopaminergic neurons in the ventral tegmental area. Brain Research 348 (1985) 201-203
    • (1985) Brain Research , vol.348 , pp. 201-203
    • Gessa, G.L.1    Muntoni, F.2    Collu, M.3    Vargiu, L.4    Mereu, G.5
  • 23
    • 4444300234 scopus 로고    scopus 로고
    • The role of mesolimbic dopamine in the development and maintenance of ethanol reinforcement
    • Gonzales R.A., Job M.O., and Doyon W.M. The role of mesolimbic dopamine in the development and maintenance of ethanol reinforcement. Pharmacology and Therapeutics 103 (2004) 121-146
    • (2004) Pharmacology and Therapeutics , vol.103 , pp. 121-146
    • Gonzales, R.A.1    Job, M.O.2    Doyon, W.M.3
  • 24
    • 0024543849 scopus 로고
    • Differential mechanisms in the acquisition and expression of heroin-induced place preference
    • Hand T.H., Stinus L., and Le Moal M. Differential mechanisms in the acquisition and expression of heroin-induced place preference. Psychopharmacology (Berlin) 98 (1989) 61-67
    • (1989) Psychopharmacology (Berlin) , vol.98 , pp. 61-67
    • Hand, T.H.1    Stinus, L.2    Le Moal, M.3
  • 25
    • 0027364036 scopus 로고
    • Ethanol differentially affects extracellular monoamines and GABA in the nucleus accumbens
    • Heidbreder C., and De Witte P. Ethanol differentially affects extracellular monoamines and GABA in the nucleus accumbens. Pharmacology Biochemistry and Behavior 46 (1993) 477-481
    • (1993) Pharmacology Biochemistry and Behavior , vol.46 , pp. 477-481
    • Heidbreder, C.1    De Witte, P.2
  • 26
    • 0025762638 scopus 로고
    • The amphetamine conditioned place preference: Differential involvement of dopamine receptor subtypes and two dopaminergic terminal areas
    • Hiroi N., and White N.M. The amphetamine conditioned place preference: Differential involvement of dopamine receptor subtypes and two dopaminergic terminal areas. Brain Research 552 (1991) 141-152
    • (1991) Brain Research , vol.552 , pp. 141-152
    • Hiroi, N.1    White, N.M.2
  • 29
    • 0026689870 scopus 로고
    • Two types of neurone in the rat ventral tegmental area and their synaptic inputs
    • Johnson S.W., and North R.A. Two types of neurone in the rat ventral tegmental area and their synaptic inputs. Journal of Physiology 450 (1992) 455-468
    • (1992) Journal of Physiology , vol.450 , pp. 455-468
    • Johnson, S.W.1    North, R.A.2
  • 31
    • 28444442694 scopus 로고    scopus 로고
    • Corticostriatal-hypothalamic circuitry and food motivation: Integration of energy, action and reward
    • Kelley A.E., Baldo B.A., Pratt W.E., and Will M.J. Corticostriatal-hypothalamic circuitry and food motivation: Integration of energy, action and reward. Physiology and Behavior 86 (2005) 773-795
    • (2005) Physiology and Behavior , vol.86 , pp. 773-795
    • Kelley, A.E.1    Baldo, B.A.2    Pratt, W.E.3    Will, M.J.4
  • 32
    • 0033913561 scopus 로고    scopus 로고
    • Neurobiology of addiction: Toward the development of new therapies
    • Glick S.D., and Maisonneuve I.M. (Eds), New York Academy of Sciences, New York
    • Koob G.F. Neurobiology of addiction: Toward the development of new therapies. In: Glick S.D., and Maisonneuve I.M. (Eds). Annals of the New York Academy of Sciences: Vol. 909. New medications for drug abuse (2000), New York Academy of Sciences, New York 170-185
    • (2000) Annals of the New York Academy of Sciences: Vol. 909. New medications for drug abuse , pp. 170-185
    • Koob, G.F.1
  • 33
    • 0022001163 scopus 로고
    • Neuroleptics block the positive reinforcing effects of amphetamine but not of morphine as measured by place conditioning
    • Mackey W.B., and van der Kooy D. Neuroleptics block the positive reinforcing effects of amphetamine but not of morphine as measured by place conditioning. Pharmacology Biochemistry and Behavior 22 (1985) 101-105
    • (1985) Pharmacology Biochemistry and Behavior , vol.22 , pp. 101-105
    • Mackey, W.B.1    van der Kooy, D.2
  • 34
    • 0642368718 scopus 로고    scopus 로고
    • The neurobiology of addiction
    • Maldonado R. The neurobiology of addiction. Journal of Neural Transmission 66 Suppl. (2003) 1-14
    • (2003) Journal of Neural Transmission , vol.66 , Issue.SUPPL , pp. 1-14
    • Maldonado, R.1
  • 35
    • 0024156733 scopus 로고
    • Ethanol with small doses of morphine establishes a conditioned place preference
    • Marglin S.H., MacKechnie D.K., Mattie M.E., Hui Y.H., and Reid L.D. Ethanol with small doses of morphine establishes a conditioned place preference. Alcohol 5 (1988) 309-313
    • (1988) Alcohol , vol.5 , pp. 309-313
    • Marglin, S.H.1    MacKechnie, D.K.2    Mattie, M.E.3    Hui, Y.H.4    Reid, L.D.5
  • 37
    • 0022919062 scopus 로고
    • The effects of haloperidol on amphetamine- and methylphenidate-induced conditioned place preferences and locomotor activity
    • Mithani S., Martin-Iverson M.T., Phillips A.G., and Fibiger H.C. The effects of haloperidol on amphetamine- and methylphenidate-induced conditioned place preferences and locomotor activity. Psychopharmacology (Berlin) 90 (1986) 247-252
    • (1986) Psychopharmacology (Berlin) , vol.90 , pp. 247-252
    • Mithani, S.1    Martin-Iverson, M.T.2    Phillips, A.G.3    Fibiger, H.C.4
  • 38
    • 0025024937 scopus 로고
    • Oral self-administration of ethanol and not experimenter-administered ethanol facilitates rewarding electrical brain stimulation
    • Moolten M., and Kornetsky C. Oral self-administration of ethanol and not experimenter-administered ethanol facilitates rewarding electrical brain stimulation. Alcohol 7 (1990) 221-225
    • (1990) Alcohol , vol.7 , pp. 221-225
    • Moolten, M.1    Kornetsky, C.2
  • 40
    • 0027173626 scopus 로고
    • Cellular responses to chronic treatment with drugs of abuse
    • Nestler E.J. Cellular responses to chronic treatment with drugs of abuse. Critical Reviews in Neurobiology 7 (1993) 23-39
    • (1993) Critical Reviews in Neurobiology , vol.7 , pp. 23-39
    • Nestler, E.J.1
  • 41
    • 0022387885 scopus 로고
    • The conditioned place preference paradigm in rats: Effect of bupropion
    • Ortmann R. The conditioned place preference paradigm in rats: Effect of bupropion. Life Sciences 37 (1985) 2021-2027
    • (1985) Life Sciences , vol.37 , pp. 2021-2027
    • Ortmann, R.1
  • 42
    • 0032143596 scopus 로고    scopus 로고
    • Expression of testosterone conditioned place preference is blocked by peripheral or intra-accumbens injection of alpha-flupenthixol
    • Packard M.G., Schroeder J.P., and Alexander G.M. Expression of testosterone conditioned place preference is blocked by peripheral or intra-accumbens injection of alpha-flupenthixol. Hormones and Behavior 34 (1998) 39-47
    • (1998) Hormones and Behavior , vol.34 , pp. 39-47
    • Packard, M.G.1    Schroeder, J.P.2    Alexander, G.M.3
  • 44
    • 0030047293 scopus 로고    scopus 로고
    • Endogenous opioids and alcohol dependence: Opioid alkaloids and the propensity to drink alcoholic beverages
    • Reid L.D. Endogenous opioids and alcohol dependence: Opioid alkaloids and the propensity to drink alcoholic beverages. Alcohol 13 (1996) 5-11
    • (1996) Alcohol , vol.13 , pp. 5-11
    • Reid, L.D.1
  • 45
    • 0021916366 scopus 로고
    • Toward understanding ethanol's capacity to be reinforcing: A conditioned place preference following injections of ethanol
    • Reid L.D., Hunter G.A., Beaman C.M., and Hubbell C.L. Toward understanding ethanol's capacity to be reinforcing: A conditioned place preference following injections of ethanol. Pharmacology Biochemistry and Behavior 22 (1985) 483-487
    • (1985) Pharmacology Biochemistry and Behavior , vol.22 , pp. 483-487
    • Reid, L.D.1    Hunter, G.A.2    Beaman, C.M.3    Hubbell, C.L.4
  • 46
    • 0026550185 scopus 로고
    • Haloperidol reduces ethanol-induced motor activity stimulation but not conditioned place preference
    • Risinger F.O., Dickinson S.D., and Cunningham C.L. Haloperidol reduces ethanol-induced motor activity stimulation but not conditioned place preference. Psychopharmacology (Berlin) 107 (1992) 453-456
    • (1992) Psychopharmacology (Berlin) , vol.107 , pp. 453-456
    • Risinger, F.O.1    Dickinson, S.D.2    Cunningham, C.L.3
  • 47
    • 12344261654 scopus 로고    scopus 로고
    • Regional heterogeneity for the intracranial self-administration of ethanol and acetaldehyde within the ventral tegmental area of alcohol-preferring (P) rats: Involvement of dopamine and serotonin
    • Rodd Z.A., Bell R.L., Zhang Y., Murphy J.M., Goldstein A., Zaffaroni A., et al. Regional heterogeneity for the intracranial self-administration of ethanol and acetaldehyde within the ventral tegmental area of alcohol-preferring (P) rats: Involvement of dopamine and serotonin. Neuropsychopharmacology 30 (2005) 330-338
    • (2005) Neuropsychopharmacology , vol.30 , pp. 330-338
    • Rodd, Z.A.1    Bell, R.L.2    Zhang, Y.3    Murphy, J.M.4    Goldstein, A.5    Zaffaroni, A.6
  • 48
    • 0842282479 scopus 로고    scopus 로고
    • Intracranial self-administration of ethanol within the ventral tegmental area of male Wistar rats: Evidence for involvement of dopamine neurons
    • Rodd Z.A., Melendez R.I., Bell R.L., Kuc K.A., Zhang Y., Murphy J.M., et al. Intracranial self-administration of ethanol within the ventral tegmental area of male Wistar rats: Evidence for involvement of dopamine neurons. Journal of Neuroscience 24 (2004) 1050-1057
    • (2004) Journal of Neuroscience , vol.24 , pp. 1050-1057
    • Rodd, Z.A.1    Melendez, R.I.2    Bell, R.L.3    Kuc, K.A.4    Zhang, Y.5    Murphy, J.M.6
  • 49
    • 0034098979 scopus 로고    scopus 로고
    • Regional heterogeneity for the intracranial self-administration of ethanol within the ventral tegmental area of female Wistar rats
    • Rodd-Henricks Z.A., McKinzie D.L., Crile R.S., Murphy J.M., and McBride W.J. Regional heterogeneity for the intracranial self-administration of ethanol within the ventral tegmental area of female Wistar rats. Psychopharmacology (Berlin) 149 (2000) 217-224
    • (2000) Psychopharmacology (Berlin) , vol.149 , pp. 217-224
    • Rodd-Henricks, Z.A.1    McKinzie, D.L.2    Crile, R.S.3    Murphy, J.M.4    McBride, W.J.5
  • 51
    • 0034767606 scopus 로고    scopus 로고
    • Predictors and prevention of nonfatal overdose among street-recruited injection heroin users in the San Francisco Bay Area, 1998-1999
    • Seal K.H., Kral A.H., Gee L., Moore L.D., Bluthenthal R.N., Lorvick J., et al. Predictors and prevention of nonfatal overdose among street-recruited injection heroin users in the San Francisco Bay Area, 1998-1999. American Journal of Public Health 91 (2001) 1842-1846
    • (2001) American Journal of Public Health , vol.91 , pp. 1842-1846
    • Seal, K.H.1    Kral, A.H.2    Gee, L.3    Moore, L.D.4    Bluthenthal, R.N.5    Lorvick, J.6
  • 52
    • 0020053666 scopus 로고
    • Parameters of low-dose ethanol intravenous self-administration in the rat
    • Sinden J.D., and Le Magnen J. Parameters of low-dose ethanol intravenous self-administration in the rat. Pharmacology Biochemistry and Behavior 16 (1982) 181-183
    • (1982) Pharmacology Biochemistry and Behavior , vol.16 , pp. 181-183
    • Sinden, J.D.1    Le Magnen, J.2
  • 55
    • 0022517950 scopus 로고
    • Conditioned place aversion mediated by orally self-administered ethanol in the rat
    • Stewart R.B., and Grupp L.A. Conditioned place aversion mediated by orally self-administered ethanol in the rat. Pharmacology Biochemistry and Behavior 24 (1986) 1369-1375
    • (1986) Pharmacology Biochemistry and Behavior , vol.24 , pp. 1369-1375
    • Stewart, R.B.1    Grupp, L.A.2
  • 57
    • 0035028059 scopus 로고    scopus 로고
    • Effect of acamprosate and naltrexone, alone or in combination, on ethanol consumption
    • Stromberg M.F., Mackler S.A., Volpicelli J.R., and O'Brien C.P. Effect of acamprosate and naltrexone, alone or in combination, on ethanol consumption. Alcohol 23 (2001) 109-116
    • (2001) Alcohol , vol.23 , pp. 109-116
    • Stromberg, M.F.1    Mackler, S.A.2    Volpicelli, J.R.3    O'Brien, C.P.4
  • 61
    • 0038635946 scopus 로고    scopus 로고
    • The effects of alprazolam on conditioned place preferences produced by intravenous heroin
    • Walker B.M., and Ettenberg A. The effects of alprazolam on conditioned place preferences produced by intravenous heroin. Pharmacology Biochemistry and Behavior 75 (2003) 75-80
    • (2003) Pharmacology Biochemistry and Behavior , vol.75 , pp. 75-80
    • Walker, B.M.1    Ettenberg, A.2
  • 62
    • 29244448701 scopus 로고    scopus 로고
    • Intra-ventral tegmental area heroin-induced place preferences in rats are potentiated by peripherally administered alprazolam
    • Walker B.M., and Ettenberg A. Intra-ventral tegmental area heroin-induced place preferences in rats are potentiated by peripherally administered alprazolam. Pharmacology Biochemistry and Behavior 82 (2005) 470-477
    • (2005) Pharmacology Biochemistry and Behavior , vol.82 , pp. 470-477
    • Walker, B.M.1    Ettenberg, A.2
  • 63
    • 2642519680 scopus 로고    scopus 로고
    • Dopamine, learning and motivation
    • Wise R.A. Dopamine, learning and motivation. Nature Reviews Neuroscience 5 (2004) 483-494
    • (2004) Nature Reviews Neuroscience , vol.5 , pp. 483-494
    • Wise, R.A.1
  • 64
    • 0032797572 scopus 로고    scopus 로고
    • Baclofen inhibits heroin self-administration behavior and mesolimbic dopamine release
    • Xi Z.X., and Stein E.A. Baclofen inhibits heroin self-administration behavior and mesolimbic dopamine release. Journal of Pharmacology and Experimental Therapeutics 290 (1999) 1369-1374
    • (1999) Journal of Pharmacology and Experimental Therapeutics , vol.290 , pp. 1369-1374
    • Xi, Z.X.1    Stein, E.A.2
  • 65
    • 0034493850 scopus 로고    scopus 로고
    • Role of D(1) and D(2) dopamine receptors in the acquisition and expression of flavor-preference conditioning in sham-feeding rats
    • Yu W.Z., Silva R.M., Sclafani A., Delamater A.R., and Bodnar R.J. Role of D(1) and D(2) dopamine receptors in the acquisition and expression of flavor-preference conditioning in sham-feeding rats. Pharmacology Biochemistry and Behavior 67 (2000) 537-544
    • (2000) Pharmacology Biochemistry and Behavior , vol.67 , pp. 537-544
    • Yu, W.Z.1    Silva, R.M.2    Sclafani, A.3    Delamater, A.R.4    Bodnar, R.J.5


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.