Psychopharmacology (Berl). 1986;89(3):311-6.
Lithium and bupropion antagonise the phasic changes in locomotor activity caused by dopamine infused into the rat nucleus accumbens.

Barnes JC, Costall B, Domeney AM, Naylor RJ.

Dopamine infused persistently (25 micrograms/24 h for 13 days) into the nucleus accumbens of rat brain caused phasic increases in spontaneous locomotor activity during the period of infusion. This phasic responding was prevented by lithium administered throughout the infusion period in divided doses (3 X daily administrations of 2.5 mg/kg IP) or as a continuous IP infusion (7.5 mg/kg/24 h), and by bupropion treatment (5-20 mg/kg 3 X daily). In contrast, imipramine, amitriptyline and nomifensine failed to prevent the phasic locomotor response to dopamine at doses which did not by themselves cause marked motor changes. Locomotor activity was measured using individual photocell cages, and rats preselected to (-)NPA were those initially showing a modest locomotor activity. Fourteen to twenty-eight days after discontinuing the dopamine infusion rats showed increased responsiveness to (-)NPA which persisted throughout the remainder of the 70-day withdrawal period. This long-term change was prevented when lithium was given continuously throughout the period of dopamine infusion, but not when lithium was given in divided doses, showing the importance of the mode of drug delivery. The long-term change caused by the dopamine infusion could also be prevented by bupropion but not by imipramine, amitriptyline or nomifensine to show again that the actions of classical antidepressant drugs may be differentiated from those of lithium and bupropion. Therefore, it is suggested that the model of phasic hyperactivity described may provide a means for more closely analysing, both behaviourally and biochemically, the site and mechanism of action of lithium (and bupropion) in the control of the short- and long-term consequences of an enhanced mesolimbic dopamine activity.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3088656&dopt=Abstract Bupropion Wellbutrin




Psychopharmacology (Berl). 1986;89(4):404-8.
The effect of experimentally-induced renal failure on accumulation of bupropion and its major basic metabolites in plasma and brain of guinea pigs.

DeVane CL, Laizure SC, Cameron DF.

Dosage regimen adjustments because of poor renal function are often assumed to be unnecessary for extensively metabolized antidepressants. This assumption is being increasingly questioned in recognition of the role of active drug metabolites. The purpose of this study was to assess the steady-state accumulation of the new antidepressant bupropion and its three major basic metabolites in guinea pigs, with and without experimentally-induced renal failure. Two groups of guinea pigs were treated by intraperitoneal (IP) implantation of mini-osmotic pumps containing bupropion hydrochloride. Immediately after surgery, one group of animals received an injection of uranyl nitrate. After 4 days, all animals were sacrificed by decapitation following blood removal by cardiac puncture. Analysis of plasma and brain samples by high performance liquid chromatography (HPLC) for concentrations of bupropion (BUP) and its major basic metabolites, the erythro-amino alcohol (EB), the threo-amino alcohol (TB) and the hydroxy metabolite (HB) revealed greater accumulation of BUP, TB, and HB in plasma and brain of the animals with renal failure compared to controls. No difference was found between groups in the concentrations of the EB metabolite. As the guinea pig shows a BUP and metabolite plasma concentration profile similar to that seen in human studies, these results suggest that further studies of bupropion and its major metabolites are warranted in patients with impaired renal function to assess possible excessive drug and metabolite accumulation.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3092270&dopt=Abstract Bupropion Wellbutrin




Can J Psychiatry. 1986 Aug;31(6):581-5.
Bupropion effects in attention deficit and conduct disorders.

Simeon JG, Ferguson HB, Van Wyck Fleet J.

Children with Attention Deficit and/or Conduct Disorders were treated with bupropion, a new antidepressant, to determine its clinical, cognitive, and EEG effects. Seventeen male patients (age range 7 to 13.4 years; mean 10.4) participated in an open clinical trial consisting of a baseline placebo period (4 weeks), bupropion therapy (8 weeks), and post-drug placebo (2 weeks). Evaluations included clinical assessments, parents, teachers, and self-ratings; cognitive tests and blood level measurements of bupropion. Fifteen patients received a daily maximum of 150 mg, one received 100 mg and one 50 mg. Clinical global improvement with bupropion therapy was marked in 5 patients, moderate in 7, mild in 2, and none in 3. The Children's Psychiatric Rating Scale indicated improvements of hyperactivity, withdrawal, anxiety, hostility/uncooperativeness, sleep disorder, antisocial behaviour, neuroticism, depression and eating disturbance. Parents' Questionnaires indicated significant improvements of conduct disorder, anxiety, hyperactivity, muscle tension and psychosomaticism. While no single cognitive test showed significant improvement, all nine tests changed in the positive direction. Adverse effects were infrequent, transient and mild. There were no clinically significant changes of the laboratory values and vital signs. Two weeks following bupropion discontinuation, clinical global improvement was maintained in 8 patients, 7 showed relapses, while 2 remained unimproved. Analyses of computerized EEG revealed that degree of clinical improvement was indexed by baseline EEG parameters and that there were significant bupropion effects on EEG measures. Double-blind trials of bupropion are recommended in child psychiatry disorders.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3093046&dopt=Abstract Bupropion Wellbutrin




Xenobiotica. 1987 Mar;17(3):287-98.
Pharmacological significance of the species differences in bupropion metabolism.

Welch RM, Lai AA, Schroeder DH.

Bupropion provided a dose-dependent prevention of tetrabenazine-induced sedation in mice but not rats. Bupropion was extensively metabolized in mice, rats, dogs and man. About 85% of the dose was excreted in urine of rats and man. The predominant metabolites in rat urine were side chain cleavage products of bupropion (m-chlorobenzoic acid) with a minor fraction consisting of basic side chain hydroxylated metabolites. Mice, dogs and man form a major side chain hydroxylated product (BW 306U) which appeared in higher concentration than bupropion in plasma of these species but not rats. The relatively high plasma levels of BW 306U in mice but not rats may account for the species difference in pharmacological response observed with bupropion.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3107223&dopt=Abstract Bupropion Wellbutrin




Gen Pharmacol. 1988;19(2):201-4.
Anorectic and behavioural effects of bupropion.

Zarrindast MR, Hosseini-Nia T.

Department of Pharmacology, Faculty of Medicine, University of Tehran, Iran.

1. Bupropion (12.5-75 mg kg-1) was given intraperitoneally to rats and was found to decrease the food consumption of the animals dose-dependently. While phenoxybenzamine, propranolol and methergoline failed to antagonize the anorectic effect of the drug; pimozide a dopamine receptor blocker decreased anorexia induced by bupropion. 2. Bupropion (12.5-50 mg kg-1) also caused a marked increase in locomotor activity of the rats. The increase in locomotion produced by bupropion was completely antagonized by pretreatment of the animals with pimozide and reserpine plus a-methyl-p-tyrosine, but not by pretreatment with phenoxybenzamine, propranolol or methergoline. 3. Taking into considerations the evidences of dopaminergic properties of bupropion shown by the others, it could be suggested that the anorexia and hyperactivity produced by bupropion may be induced through the indirect dopaminergic mechanism.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3127269&dopt=Abstract Bupropion Wellbutrin