Further characterization of the effect of the prototypical antidepressant imipramine on the microstructure of licking for sucrose

Dopamine, activation of ingestion and evaluation of response efficacy: a focus on the within-session time-course of licking burst number

RATIONALE

Evidence on the effect of dopamine D1-like and D2-like receptor antagonists on licking microstructure and the forced swimming response led us to suggest that (i) dopamine on D1-like receptors plays a role in activating reward-directed responses and (ii) the level of response activation is reboosted based on a process of evaluation of response efficacy requiring dopamine on D2-like receptors. A main piece of evidence in support of this hypothesis is the observation that the dopamine D2-like receptor antagonist raclopride induces a within-session decrement of burst number occurring after the contact with the reward. The few published studies with a detailed analysis of the time-course of this measure were conducted in our laboratory.

OBJECTIVES

The aim of this review is to recapitulate and discuss the evidence in support of the analysis of the within-session burst number as a behavioural substrate for the study of the mechanisms governing ingestion, behavioural activation and the related evaluation processes, and its relevance in the analysis of drug effects on ingestion.

CONCLUSIONS

The evidence gathered so far suggests that the analysis of the within-session time-course of burst number provides an important behavioural substrate for the study of the mechanisms governing ingestion, behavioural activation and the related evaluation processes, and might provide decisive evidence in the analysis of the effects of drugs on ingestion. However, further evidence from independent sources is necessary to validate the use and the proposed interpretation of this measure.

Molecular Basic of Pharmacotherapy of Cytokine Imbalance as a Component of Intervertebral Disc Degeneration Treatment

Intervertebral disc degeneration (IDD) and associated conditions are an important problem in modern medicine. The onset of IDD may be in childhood and adolescence in patients with a genetic predisposition. With age, IDD progresses, leading to spondylosis, spondylarthrosis, herniated disc, spinal canal stenosis. One of the leading mechanisms in the development of IDD and chronic back pain is an imbalance between pro-inflammatory and anti-inflammatory cytokines. However, classical therapeutic strategies for correcting cytokine imbalance in IDD do not give the expected response in more than half of the cases. The purpose of this review is to update knowledge about new and promising therapeutic strategies based on the correction of the molecular mechanisms of cytokine imbalance in patients with IDD. This review demonstrates that knowledge of the molecular mechanisms of the imbalance between pro-inflammatory and anti-inflammatory cytokines may be a new key to finding more effective drugs for the treatment of IDD in the setting of acute and chronic inflammation.

Combinatorial Regimen of Carbamazepine and Imipramine Exhibits Synergism against Grandmal Epilepsy in Rats: Inhibition of Pro-Inflammatory Cytokines and PI3K/Akt/mTOR Signaling Pathway

Epilepsy is a neurodegenerative disorder that causes recurring seizures. Thirty-five percent of patients remain refractory, with a higher prevalence of depression. We investigated the anticonvulsant efficacy of carbamazepine (CBZ; 20 and 50 mg/kg), imipramine (IMI; 10 and 20 mg/kg) alone, and as a low dose combination. This preclinical investigation included dosing of rats for 14 days followed by elicitation of electroshock on the last day of treatment. Along with behavioral monitoring, the rat hippocampus was processed for quantification of mTOR, IL-1β, IL-6 and TNF-α levels. The histopathological analysis of rat hippocampus was performed to ascertain neuroprotection. In vitro studies and in silico studies were also conducted. We found that the low dose combinatorial therapy of CBZ (20 mg/kg) + IMI (10 mg/kg) exhibits synergism (p < 0.001) in abrogation of maximal electroshock (MES) induced convulsions/tonic hind limb extension (THLE), by reducing levels of pro-inflammatory cytokines, and weakening of the PI3K/Akt/mTOR signal. The combination also exhibits cooperative binding at the Akt. As far as neuroprotection is concerned, the said combination increased cell viability by 166.37% compared to Pentylenetetrazol (PTZ) treated HEK-293 cells. Thus, the combination of CBZ (20 mg/kg) + IMI (10 mg/kg) is a fruitful combination therapy to elevate seizure threshold and provide neuroprotection.