When exposed to a hypoxic environment the body's first response is a reflex increase in ventilation, termed the hypoxic ventilatory response (HVR). With chronic sustained hypoxia (CSH), such as during acclimatization to high altitude, an additional time-dependent increase in ventilation occurs, which increases the HVR. This secondary increase persists after exposure to CSH and involves plastici...

The intrinsic mechanisms that promote the degeneration of retinal ganglion cells (RGCs) following the activation of N-Methyl-D-aspartic acid-type glutamate receptors (NMDARs) are unclear. In this study, we have investigated the role of downstream regulatory element antagonist modulator (DREAM) in NMDA-mediated degeneration of the retina. NMDA, phosphate-buffered saline (PBS), and MK801 were inj...

Targeting group II metabotropic glutamate receptors (mGluR2/3) has been proposed to correct the dysfunctional glutamatergic system, particularly NMDA receptor (NMDAR) hypofunction, for treatment of schizophrenia. However, how activation of mGluR2/3 affects NMDAR function in adult animals remains elusive. Here we show the effects of LY395756 (LY39), a compound acting as both an mGluR2 agonist an...

Background. Volatile anesthetics reduce neuronal excitation and cerebral metabolism but can also increase intracellular water accumulation in normal and injured brains. While attenuation of neuronal excitation and glutamate release are beneficial under pathological conditions, any increase in edema formation should be avoided. In the present study we investigated duration-dependent effects of t...

The dorsal nucleus of the little skate is a cerebellum-like sensory structure that adaptively filters out predictable electrosensory inputs. The filter's plasticity is mediated by anti-Hebbian associative depression at the synapses between parallel fibers and ascending efferent neurons (AENs). Changes in synaptic strength are indicated by the formation of a cancellation signal which is initiate...

Since an ethical issue has been raised regarding the use of the well-known anesthetic agent chloral hydrate, owing to its mutagenic and carcinogenic effects in animals, attention of neuroscientists has turned to finding out an alternative agent able to meet not only potency, safety, and analgesic efficacy, but also reduced neuroprotective effect for stroke research. The aim of this study was to...

Small G proteins including Rac are mediators of changes in neuronal morphology associated with synaptic plasticity. Previous studies in our laboratory showed that Rac is highly expressed in the adult mouse hippocampus, a brain area that exhibits robust synaptic plasticity and is crucial for the acquisition of memories. In this study, we investigated whether Rac was involved in NMDA receptor-dep...

PURPOSE Glutamate antagonists can block ganglion cell death due to optic nerve crush. Although most investigators have focused on blockade of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor, we have chosen to evaluate the efficacy of blockade of the AMPA-kainate (KA) receptor in this experimental paradigm. METHODS The optic nerves of rats were crushed, and ganglion cell survival...