Medium supplementation with zinc enables detection of imipramine-induced adaptation in glycine/NMDA receptors labeled with [3H]L-689,560.
Journal Title: Pharmacological Reports - Year 2006, Vol 58, Issue 5
Abstract
Antidepressant drugs after chronic administration induce adaptive changes in the NMDA receptor complex. Radioligand-receptorbinding studies using [3H]5,7-dichlorokynurenic acid demonstrated a "down-regulation" of the glycine site/NMDA receptor following chronic treatment with antidepressants and electroconvulsive shock. However, binding procedure using this radioligand is time consuming because it requires the use of centrifugation method in the separation process. The introduction of a new radioligand of glycine/NMDA receptor, [3H]L-689,560 enables the application of a rapid filtration method. In the present study we demonstrate that 2-week treatment with imipramine (15 mg/kg ip) did not evoke alterations in specific [3H]L-689,560 binding and in IC50 value of glycine in displacing [3H]L-689,560 binding in the mouse or rat cortex. However, longer, a 4-week treatment with imipramine induced a significant 71% increase in IC50 value in displacing [3H]L-689.560 binding in the mouse cortex. Moreover, the presence of zinc in the incubation media, dose-dependently enhances detection of imipramine-induced increase in IC50 value of glycine in displacing [3H]L-689,560 binding in the rat cortex. The present data indicate that: (1) [3H]L-689,560 may be a suitable ligand for assessing adaptation of the glycine/NMDA sites and (2) the presence of zinc enhances detection of imipramine-induced reduction of glycine affinity for glycine/NMDA receptors labeled with [3H]L-689,560 which further indicates a significance of zinc in the mechanism of antidepressant treatment.
Authors and Affiliations
Małgorzata Dybała, Dorota Maciąg, Agnieszka Cichy, Lucyna Pomierny-Chamioło, Anna Partyka, Tadeusz Librowski, Gabriel Nowak
1,2-Diazole prevents cisplatin-induced nephrotoxicity in experimental rats.
Cisplatin (a platinum-compound) is a anti-neoplastic drug used in the treatment of various cancers but eventually results in severe adverse effects namely nephrotoxicity or renal disorder through generation of reactive o...
Vasopressor and heart rate responses to systemic administration of bombesin in anesthetized rats.
The aim of the present study was to investigate the effects of aortic depressor nerve (ADN) transection, supranodosal vagi denervation (NG vagi cut) and adrenergic receptor blocker treatment on the cardiovascular respons...
Effects of chromium picolinate on vascular reactivity and cardiac ischemia-reperfusion injury in spontaneously hypertensive rats.
Chromium picolinate [Cr(pic)(3)] is a nutritional supplement widely promoted to exert beneficial metabolic effects in patients with type 2 diabetes/impaired glucose tolerance. Frequent comorbidities in these individuals...
Effect of benzothiazole/piperazine derivatives on intracerebroventricular streptozotocin-induced cognitive deficits.
Background: In this study, benzothiazole-piperazine compounds were synthesized by condensing the functional groups of donepezil (DNP), FK-960, and sabeluzole, which are known to have therapeutic potential against Alzheim...
Influence of NADPH oxidase inhibition on oxidative stress parameters in rat hearts.
The aim of this study was to assess whether apocynin, an nicotinamide adenine dinucleotide phosphate (NADPH) oxidase blocker, influences lipid peroxidation TBARS, hydrogen peroxide (H2O2) content, protein level, heart ed...