[1] Behavioral Neuroscience Branch,
[2] National Institute on Drug Abuse – Intramural Research Program,undefined
[3] 5500 Nathan Shock Drive,undefined
[4] Baltimore,undefined
[5] MD 21224,undefined
[6] USA,undefined
[7] Maryland Psychiatric Research Center,undefined
[8] University of Maryland,undefined
[9] P.O. Box 21247,undefined
[10] Baltimore,undefined
[11] MD 21228,undefined
[12] USA,undefined
[13] Laboratory of Molecular and Developmental Neuroscience,undefined
[14] MGH-East,undefined
[15] Charlestown,undefined
[16] MA 02129,undefined
[17] USA,undefined
[18] Laboratory of Experimental Psychology,undefined
[19] School of Biological Sciences,undefined
[20] University of Sussex,undefined
[21] Brighton BN1 9QG,undefined
[22] UK,undefined
[23] Current address: Department of Pharmacology,undefined
[24] Merck Research Laboratories,undefined
[25] R80Y-140,undefined
[26] P.O. Box 2000,undefined
[27] Rahway,undefined
[28] NJ 07065,undefined
[29] USA,undefined