Involvement of AMPA receptors for Mesobuthus tamulus Pocock venom-induced depression of monosynaptic reflex in neonatal rat spinal cord in vitro.

Glutamate is a putative neurotransmitter at Ia-alpha motoneuron synapse in the spinal cord and mediate the action via N-methyl-D-aspartate (NMDA) and a-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) receptors. Since NMDA receptors are not involved in M. tamulus Pocock (MBT) venom-induced depression of spinal monosynaptic reflex (MSR), the present study was undertaken to evaluate the role of AMPA receptors in mediating the depression of MSR by MBT venom.

Involvement of NO-guanylyl cyclase pathway for the depression of spinal monosynaptic reflex by Mesobuthus tamulus venom in neonatal rat in vitro.

Aims: The present study was undertaken to evaluate the role of nitric oxide (NO) in Mesobuthus tamulus (MBT) venom-induced depression of spinal reflexes.

Main Methods: Experiments were performed on isolated hemisected spinal cords from 4 to 6day old rats. Stimulation of a dorsal root with supramaximal strength evoked monosynaptic (MSR) and polysynaptic reflex (PSR) potentials in the corresponding segmental ventral root.

Involvement of 5-hydroxytryptaminergic transmission for the Mesobuthus tamulus venom-induced depression of spinal reflexes in neonatal rat in vitro.

Mesobuthus tamulus (MBT) venom is shown to depress the spinal reflexes through a mechanism unrelated to the NMDA receptors. 5-Hydroxytryptamine (5-HT) is another excitatory transmitter in the spinal cord therefore, the present study was undertaken to examine the involvement of 5-HT in the venom-induced depression of reflexes. The experiments were performed on isolated hemisected spinal cords from 4 to 6-day-old rats.

Indian red scorpion venom depresses spinal synaptic transmission without involving NMDA receptors.

Stings of Indian red scorpion (Mesobuthus tamulus, MBT) produce neurological abnormalities such as convulsions and paralysis. These parameters indicate the activity at alpha-motoneuron. The present study was therefore, undertaken to evaluate the effect of MBT-venom on spinal reflexes and the involvement of N-methyl-d-aspartate (NMDA) receptors.

5-HT-induced depression of the spinal monosynaptic reflex potential utilizes different types of 5-HT receptors depending on Mg2+ availability.

Receptor subtypes involved in the 5-hydroxytryptamine (5-HT)-induced depression of synaptic transmission in neonatal rat spinal cords in vitro were evaluated in the absence or presence of Mg(2+) in the medium. Stimulation of a dorsal root evoked monosynaptic reflex potential (MSP) and polysynaptic reflex potential (PSP) in the segmental ventral root in Mg(2+)-free medium where the voltage-dependent blockade of NMDA receptors is absent. The 5-HT (0.