GET73 Increases Rat Extracellular Hippocampal CA1 GABA Levels Through a Possible Involvement of Local mGlu5 Receptor.

GET73 increases rat extracellular hippocampal CA1 GABA levels through a possible involvement of local mGlu5 receptor.

Synapse. 2013 Apr 8;
Beggiato S, O’Connor WT, Tomasini MC, Antonelli T, Loche A, Tanganelli S, Cacciaglia R, Ferraro L

N-[(4-trifluoromethyl) benzyl] 4-methoxybutyramide (GET73) is a newly synthesized compound displaying anti-alcohol and anxiolytic properties. In light of the importance of the hippocampal CA1 subregion in alcohol addiction and anxiety-like behaviours – this in vivo microdialysis study characterized the effect of GET73 on extracellular GABA levels in the hippocampal CA1 region of the freely moving rat – including a possible role for mGlu5 receptor in mediating this effect. Both intraperitoneal administration (2-10 mg/kg) and local intra-hippocampal CA1 perfusion with GET73 (50-1000 nM) were associated with a transient, step-wise increase in dialysate hippocampal CA1 GABA levels. The GET73 (10 mg/kg)-induced increase in GABA levels was not affected by intra-CA1 perfusion with either the GABA reuptake inhibitor SKF89976A (0.5 mM) or by local GABAA (bicuculline; 1?M) and GABAB (CGP35348; 500 ?M) receptor antagonists. On the contrary, the GET73-induced increase in GABA levels was partially counteracted by the intra-CA1 perfusion with the mGlu5 receptor negative allosteric modulator MPEP (300 µM). Interestingly, GET73 at the lowest (2 mg/kg) dose tested, by itself ineffective, fully counteracted the increase in GABA levels induced by the mGlu5 receptor agonist CHPG (1000 µM). Taken together, these findings suggest that the GET73-induced increase in hippocampal CA1 GABA levels operates independently of local GABA reuptake and/or GABAA or GABAB receptors. Furthermore, the present data lead to hypothesize a possible interaction between GET73 and mGluR5-mediated regulation of hippocampal CA1 GABA transmission, an effect which may be relevant to the ability of GET73 to reduce alcohol intake in an alcohol-preferring rat strain. Synapse, 2013. © 2013 Wiley Periodicals, Inc. HubMed – addiction

 

Addressing alcohol addiction: lessons from a hospital based audit.

Indian J Med Res. 2013 Feb; 137(2): 394-6
Chand P, Naveen CK, Murthy P, Isaac M

HubMed – addiction

 

Chronic co-administration of nicotine and methamphetamine causes differential expression of immediate early genes in the dorsal striatum and nucleus accumbens.

Neuroscience. 2013 Apr 3;
Saint-Preux F, Rodríguez Bores L, Tulloch I, Ladenheim B, Kim R, Thanos PK, Volkowb ND, Lud Cadet J

Nicotine and methamphetamine (METH) cause addiction by triggering neuroplastic changes in brain reward pathways though they each engage distinct molecular targets (nicotine receptors and dopamine transporters respectively). Addiction to both drugs is very prevalent, with the vast majority of METH users being also smokers of cigarettes. This co-morbid occurrence thus raised questions about potential synergistic rewarding effects of the drugs. However, few studies have investigated the chronic neurobiological changes associated with co-morbid nicotine and METH addiction. Here we investigated the effects of these two drugs alone and in combination on the expression of several immediate early genes (IEGs) that are sensitive to drug exposures. Chronic exposure to either nicotine or METH caused significant decreases in the expression of fosb, fra1, and fra2 in the nucleus accumbens (NAc) but not in the dorsal striatum whereas the drug combination increased fra2 expression in both structures. Except for junB mRNA levels that were decreased by the three drug treatments in the NAc, there were no significant changes in the Jun family members. Of the Egr family members, NAc egr2 expression was decreased after nicotine and the drug combination whereas NAc egr3 was decreased after METH and the drug combination. The drug combination also increased striatal egr3 expression. The Nr4a family member, nr4a2/nurr1, showed increased striatal expression after all 3 drug treatments, while striatal nr4a3/nor-1 expression was increased by the drug combination whereas NAc nr4a1/nurr77 was decreased by nicotine and the drug combination. These observations suggest that, when given in combination, the two drugs exert distinct effects on the expression of IEGs in dopaminergic projection areas from those elicited by each drug alone. The significance of these changes in IEG expression and in other molecular markers in fostering co-morbid METH and nicotine abuse needs to be further evaluated. HubMed – addiction

 

Pharmacist-led management of chronic pain in primary care: results from a randomised controlled exploratory trial.

BMJ Open. 2013; 3(4):
Bruhn H, Bond CM, Elliott AM, Hannaford PC, Lee AJ, McNamee P, Smith BH, Watson MC, Holland R, Wright D

To compare the effectiveness of pharmacist medication review, with or without pharmacist prescribing, with standard care, for patients with chronic pain.An exploratory randomised controlled trial.Six general practices with prescribing pharmacists in Grampian (3) and East Anglia (3).Patients on repeat prescribed pain medication (4815) were screened by general practitioners (GPs), and mailed invitations (1397). 196 were randomised and 180 (92%) completed. Exclusion criteria included: severe mental illness, terminally ill, cancer related pain, history of addiction. RANDOMISATION AND INTERVENTION: Patients were randomised using a remote telephone service to: (1) pharmacist medication review with face-to-face pharmacist prescribing; (2) pharmacist medication review with feedback to GP and no planned patient contact or (3) treatment as usual (TAU). Blinding was not possible.Outcomes were the SF-12v2, the Chronic Pain Grade (CPG), the Health Utilities Index 3 and the Hospital Anxiety and Depression Scale (HADS). Outcomes were collected at 0, 3 and 6 months.In the prescribing arm (n=70) two patients were excluded/nine withdrew. In the review arm (n=63) one was excluded/three withdrew. In the TAU arm (n=63) four withdrew. Compared with baseline, patients had an improved CPG in the prescribing arm, 47.7% (21/44; p=0.003) and in the review arm, 38.6% (17/44; p=0.001), but not the TAU group, 31.3% (15/48; ns). The SF-12 Physical Component Score showed no effect in the prescribing or review arms but improvement in TAU (p=0.02). The SF-12 Mental Component Score showed no effect for the prescribing or review arms and deterioration in the TAU arm (p=0.002). HADS scores improved within the prescribing arm for depression (p=0.022) and anxiety (p=0.007), between groups (p=0.022 and p=0.045, respectively).This is the first randomised controlled trial of pharmacist prescribing in the UK, and suggests that there may be a benefit for patients with chronic pain. A larger trial is required. Trial registration: www.isrctn.org/ISRCTN06131530. Medical Research Council funding. HubMed – addiction