introduction: appropriate thyroid hormone (th) levels are essential during the critical period of brain development, which is associated with the growth of axons and dendrites and synapse formation. in rats, oral motor circuits begin to reach to their adult pattern around 3 weeks after birth, the period in which alteration from sucking to biting and chewing occurs (weaning time). trigeminal mot...

CGRP, which coexists with acetylcholine in trigeminal motoneurons, could be one of the regulatory anterograde factors responsible for the enhanced expression of AChR subunits in neuromuscular junction. It has been also shown that low level of thyroid hormone plasma concentration has influence on the transitional development of muscle fibers and related motoneurons through a sever reduction in A...

CGRP, which coexists with acetylcholine in trigeminal motoneurons, could be one of the regulatory anterograde factors responsible for the enhanced expression of AChR subunits in neuromuscular junction. It has been also shown that low level of thyroid hormone plasma concentration has influence on the transitional development of muscle fibers and related motoneurons through a sever reduction in A...

Introduction: Appropriate thyroid hormone (TH) levels are essential during the critical period of brain development, which is associated with the growth of axons and dendrites and synapse formation. In rats, oral motor circuits begin to reach to their adult pattern around 3 weeks after birth, the period in which alteration from sucking to biting and chewing occurs (weaning time). Trigeminal ...

The dopamine system plays an integral role in motor physiology. Dopamine controls movement by modulation of higher-order motor centers (e.g., basal ganglia) but may also regulate movement by directly controlling motoneuron function. Even though dopamine cells synapse onto motoneurons, which themselves express dopamine receptors, it is unknown whether dopamine modulates skeletal muscle activity....

The prey-catching behavior of the frog is a complex, well-timed sequence of stimulus response chain of movements. After visual analysis of the prey, a size dependent program is selected in the motor pattern generator of the brainstem. Besides this predetermined feeding program, various direct and indirect sensory inputs provide flexible adjustment for the optimal contraction of the executive mu...

We studied how metabotropic glutamate receptor (mGluR) activation modifies the synaptic and intrinsic membrane properties of neonatal rat trigeminal motoneurons using the broad-spectrum mGluR agonist (1S,3R)-1-amino-1,3-cyclopentane-dicarboxylic acid [(1S,3R)-ACPD], group I/II antagonist (+/-)-alpha-methyl-4-carboxy-phenylglycine (MCPG), and group III agonist L-2-amino-4-phosphonobutanoate (L-A...

The trigeminal loop in the brainstem comprises the innermost level of sensorimotor feedback in the rat vibrissa system. Anatomy suggests that this loop relays tactile information from the vibrissae to the motoneurons that control vibrissa movement. We demonstrate, using in vitro and in vivo recordings, that the trigeminal loop consists of excitatory pathways from vibrissa sensory inputs to vibr...

The physiological consequences of the noradrenergic (NE) hyperinnervation of the rat brain stem produced by neonatal administration of 6-hydroxydopamine (6-OHDA) was studied in the motor trigeminal nucleus. Stimulation of the region of the lateral lemniscus, the source of the noradrenergic innervation of the nucleus, facilitated the masseteric reflex for up to 200 msec in both normal and hyperi...