AIM To evaluate the effects of melatonin on antioxidant enzyme levels and histopathologic changes in dizocilpine (MK-801)-induced psychosis model rat testis. METHODS A total of 24 adult male Wistar-Albino rats were divided into three groups with 8 in each. Group I was used as control. Rats in Group II were injected with MK-801 (0.5 mg/kg body weight i.p. for 5 days). In addition to MK-801, me...

The relationship between the effects of the N-methyl-D-aspartate (NMDA) antagonist MK-801 on acute responses to ethanol and its ability to block ethanol sensitization and tolerance was examined in DBA/2J mice. Cross-sensitization between these drugs was also studied. Repeated administration of 0.1 mg/kg MK-801 with ethanol potentiated, whereas 0.25 mg/kg attenuated, sensitization to ethanol's l...

introduction: neuropathic pain syndromes are changes resulting from damage to neuronal pathways that are characterized by spontaneous burning sensation with accompanying allodynia and hyperalgesia. since the treatments of neuropathic pain are poorly understood and existing treatments are often ineffective, it is important to increase our understanding of the neuropathic pain states in order to ...

Direct intracerebral administration of N-methyl-D-aspartate typically produces focal brain injury. (+)-5-Methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-immi ne maleate (MK-801), a non-competitive N-methyl-D-aspartate antagonist, can protect against N-methyl-D-aspartate-mediated brain injury when administered shortly before or after an intracerebral injection of N-methyl-D-aspartate. Howev...

In rats, olfactory bulbectomy (OBX) causes changes in glutamatergic function in the amygdala (AMG) and induces mouse-killing behavior (MKB). The medial AMG (mAMG) plays an important role in the initiation and maintenance of OBX-induced MKB. In the present study, systemic injection or intra-mAMG perfusion of (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-80...

MK-801, also known as dizocilpine, is a noncompetitive N-methyl-D-aspartic acid (NMDA) receptor antagonist that induces schizophrenia-like symptoms. While astrocytes have been implicated in the pathophysiology of psychiatric disorders, including schizophrenia, astrocytic responses to MK-801 and their significance to schizotypic symptoms are unclear. Changes in the expression levels of glial fib...

Mice were administered anticholinesterase pesticides dichlorvos (DDVP) or methomyl (MET). Both DDVP and MET induced dose-dependent seizures and lethality in mice. The muscarinic antagonist atropine (ATR, 1.8 mg/kg) did not prevent seizures but diminished the lethality induced by DDVP or MET. The nicotinic antagonist mecamylamine (MEC, 1 mg/kg) affected neither DDVP-induced seizures nor DDVP- an...

It has been demonstrated that MK-801 potentiates the effects of the non-selective muscarinic antagonist scopolamine on memory in rats. In this study, we investigated the role of the M1-muscarinic receptor in this interaction, by administering different doses of dicyclomine (DIC) and MK-801 in combination to male Wistar rats before training on the inhibitory avoidance task. MK-801 and DIC in sub...

When memories are retrieved, they can enter a labile state during which the memory may be modified and subsequently restabilized through the process of reconsolidation. However, this does not occur in all situations, and certain "boundary conditions" determine whether a memory will undergo reconsolidation. Naïve male lister hooded rats were trained for 5 days to press a lever in order to retrie...

Rats increase their intake of food, but not water, after intraperitoneal injection of MK-801, a noncompetitive antagonist of N-methyl-D-aspartate-activated ion channels. We hypothesized that MK-801 might enhance intake by interfering with intestinal chemosensory signals. To test this hypothesis, we examined the effect of the antagonist on 15% sucrose intake after an intraduodenal infusion of ma...