The authors demonstrate that different NMDAR antagonists (ketamine and MK-801) have varying effects on spine density depending on dose, drug regimen, and brain region. While acute ketamine treatment increases cortical spine density in mice, subchronic exposure to either drug reduces spine density in both the cortex and striatum.

In rodents, postischemic hypothermia can provide robust and long-term functional and histological neuroprotection, even when intervention is delayed for several hours following ischemia. This generates a need to follow temperature precisely for many hours, perhaps several days if a hypothermic effect is to be studied or excluded. Such protracted temperature control (> 24 h) is difficult and oft...

The N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 has been shown to attenuate tolerance development in rats. In this study, we show that MK-801 inhibits tolerance to the antinociceptive effects of morphine, as assessed by the tail-flick test, in spinalized rats. These results suggest that NMDA receptor antagonists inhibit opiate tolerance at spinal sites, and also provide strong eviden...

The purpose of this study was to characterize the kinetics and voltage-dependence of the block of N-methyl-D-aspartate (NMDA)-induced currents in primary cultures of rat cortical neurons by the neuroprotective, low-affinity, NMDA antagonist ARL 15896AR, using whole-cell voltage-clamp techniques. ARL 15896AR caused rapid and reversible inhibition of NMDA (50 microM)-evoked currents from neurons ...

The purpose of this study was to determine whether glycine is effective in correcting the age-related change in the N-methyl-D-aspartate (NMDA) receptor complex. Autoradiographic analysis of [3H]MK801 and NMDA-displaceable [3H]glutamate binding was performed with 0, 10, 30 and 100 microM glycine on brain tissue from 3-, 10-, and 24-30-month-old C57B1 mice. Glycine, even at 10 microM, enhanced b...

Because of its highly developed social character, zebrafish is a promising model system for the study of the genetic and neurochemical basis of altered social engagement such as is common in autism and schizophrenia. The traditional shoaling paradigm investigates social cohesion in homogeneous groups of zebrafish. However, the social dynamics of mixed groups is gaining interest from a therapeut...

Numerous data have indicated that competitive and non-competitive N-methyl-D-aspartate (NMDA) receptor antagonists attenuate the development of tolerance to the analgesic effect of morphine. This study extends these findings on the effects of glycine(B) site antagonist, L-701.324. Tolerance to the analgesic effect of morphine was measured in hot-plate test in Wistar rats. For 9 days, animals we...

High doses of 3,4-methylenedioxymethamphetamine (MDMA) have been shown to cause long-lasting depletions of central serotonin (5-HT) which are indicative of neuronal toxicity. The noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (DZ) attenuates depletions of 5-HT induced by MDMA. Because DZ has been shown to induce hypothermia in rat models of ischemia, the purpose of t...

The effect of (S)-4CPG [(S)-4-carboxyphenylglycine] (25, 50, 100 nmol icv) and the effect of AP-7 (5 nmol icv) or MK-801 (5 nmol icv) on the processes of acquisition, consolidation of conditioned reflexes and locomotor activity were tested in rats. Neither AP-7, MK-801 nor (S)-4CPG given alone changed locomotor activity. MK-801 significantly increased the effects of (S)-4CPG: on crossings at al...