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Title: Multiple toxic doses of methamphetamine alter neurotensin concentrations in various region of the rat brain

Abstract

The authors have previously reported that multiple high doses of methamphetamine (METH) alter neuronal monoamine metabolism and release. Recently, Hokfelt et al. showed that neurotensin, a tridecapeptide, has neurotransmitter properties which may be involved with DA neuronal activity. In the present study they investigated the possible effects of METH on the CNS neurotensin system. Five doses of METH (15 mg/kg) were administered every 6 h; control and treated rats were sacrificed 18 h after the last dose and concentrations of neurotensin-like immuno-reactivity (NTLI) were measured by radioimmunoassay. NTLI was elevated 200-300% in the nucleus accumbens, neostriatum, and substantia nigra; 30-40% increases in NTLI were measured in the hippocampus and hypothalamus. No change was observed in amygdala, A-10 or periaqueductal gray. In contrast to the above measured areas, the frontal lobe and olfactory bulb showed decreases of 25-35%. These findings demonstrate that METH treatment alters the activities of several CNS neurotensin systems, possibly due to the influence of this drug on DA pathways. The variability in the type and magnitude of these responses suggests that DA and neurotensin systems interact by more than one mechanism.

Authors:
; ; ;
Publication Date:
Research Org.:
Univ. of Utah, Salt Lake City
OSTI Identifier:
6989221
Report Number(s):
CONF-8604222-
Journal ID: CODEN: FEPRA
Resource Type:
Conference
Resource Relation:
Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States); Journal Volume: 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
Country of Publication:
United States
Language:
English
Subject:
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; 59 BASIC BIOLOGICAL SCIENCES; AMINES; METABOLISM; AMPHETAMINES; BIOLOGICAL EFFECTS; BRAIN; IMMUNE REACTIONS; NERVES; RADIOIMMUNOASSAY; RATS; ANALEPTICS; ANIMALS; AUTONOMIC NERVOUS SYSTEM AGENTS; BODY; CENTRAL NERVOUS SYSTEM; CENTRAL NERVOUS SYSTEM AGENTS; DRUGS; IMMUNOASSAY; IMMUNOLOGY; ISOTOPE APPLICATIONS; MAMMALS; NERVOUS SYSTEM; ORGANIC COMPOUNDS; ORGANS; RADIOASSAY; RADIOIMMUNOLOGY; RODENTS; SYMPATHOMIMETICS; TRACER TECHNIQUES; VERTEBRATES 560300* -- Chemicals Metabolism & Toxicology; 550201 -- Biochemistry-- Tracer Techniques

Citation Formats

Hanson, G.R., Merchant, K., Gibb, J.W., and Letter, A.A. Multiple toxic doses of methamphetamine alter neurotensin concentrations in various region of the rat brain. United States: N. p., 1986. Web.
Hanson, G.R., Merchant, K., Gibb, J.W., & Letter, A.A. Multiple toxic doses of methamphetamine alter neurotensin concentrations in various region of the rat brain. United States.
Hanson, G.R., Merchant, K., Gibb, J.W., and Letter, A.A. 1986. "Multiple toxic doses of methamphetamine alter neurotensin concentrations in various region of the rat brain". United States. doi:.
@article{osti_6989221,
title = {Multiple toxic doses of methamphetamine alter neurotensin concentrations in various region of the rat brain},
author = {Hanson, G.R. and Merchant, K. and Gibb, J.W. and Letter, A.A.},
abstractNote = {The authors have previously reported that multiple high doses of methamphetamine (METH) alter neuronal monoamine metabolism and release. Recently, Hokfelt et al. showed that neurotensin, a tridecapeptide, has neurotransmitter properties which may be involved with DA neuronal activity. In the present study they investigated the possible effects of METH on the CNS neurotensin system. Five doses of METH (15 mg/kg) were administered every 6 h; control and treated rats were sacrificed 18 h after the last dose and concentrations of neurotensin-like immuno-reactivity (NTLI) were measured by radioimmunoassay. NTLI was elevated 200-300% in the nucleus accumbens, neostriatum, and substantia nigra; 30-40% increases in NTLI were measured in the hippocampus and hypothalamus. No change was observed in amygdala, A-10 or periaqueductal gray. In contrast to the above measured areas, the frontal lobe and olfactory bulb showed decreases of 25-35%. These findings demonstrate that METH treatment alters the activities of several CNS neurotensin systems, possibly due to the influence of this drug on DA pathways. The variability in the type and magnitude of these responses suggests that DA and neurotensin systems interact by more than one mechanism.},
doi = {},
journal = {Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)},
number = ,
volume = 45:4,
place = {United States},
year = 1986,
month = 3
}

Conference:
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