Chronic Amphetamine Facilitates Immunosuppression in Response to a Novel Aversive Stimulus: Reversal by Haloperidol Pretreatment

ANA M. BASSO,GABRIELA GIOINO, VÍCTOR A. MOLINA AND LILIANA M. CANCELA

PHARMACOLOGY BIOCHEMISTRY AND BEHAVIOR

PERGAMON-ELSEVIER SCIENCE LTD

Año: 1999 vol. 62 p. 307 - 314

0091-3057

BASSO, A. M., G. GIOINO, V. A. MOLINA AND L. M. CANCELA. Chronic amphetamine facilitates immunosuppression in response to a novel aversive stimulus: Reversal by haloperidol pretreatment. PHARMACOL BIOCHEM BEHAV 62 (2) 307–314, 1999.—The effect of chronic d -amphetamine sulfate (AMPH) treatment (nine daily injections, 2 mg/kg IP) on subsequent foot shock stress-induced immunological response was investigated. In addition, the potential role of a dopaminergic (DA) mechanism in the development of chronic AMPH-induced changes in stress-influenced immune responses was characterized. Exposure to foot shock stress decreased the percentage of T-lymphocytes, and reduced the delayed-type hypersensitivity reaction (DTH) in chronically AMPH-pretreated rats relative to vehicle-treated controls. Both of those stress-induced immunosuppressive responses were no longer evident when AMPH-pretreated rats were injected with haloperidol (HAL, 1 mg/kg IP) 30 min prior to each daily AMPH injection. The present findings are indicative of a modulatory role for dopamine in the facilitating process induced by AMPH on stress-induced immunosuppressive effects. © 1999 Elsevier Science Inc.