Three cases who underwent surgery in different areas of the craniofacial region were reported with bradycardia developing intraoperatively during flap traction. Many cases of the oculocardiac reflex during treatment of the orbital region have been reported in the literature. This manuscript recorded that reflex bradycardia can occur during traction or stretching of any structure innervated...

Trigeminal motoneurons relay the final output signals generated within the oral-motor pattern generating circuit(s) to muscles for execution of various motor patterns. In recent years, these motoneurons were shown to possess voltage dependent nonlinear membrane properties that allow them to actively participate in sculpting their final output. A complete understanding of the factors controlling...

Intracellular recordings and pharmacological manipulations were employed to investigate the ionic basis for serotonin-induced bistable membrane behaviors in guinea pig trigeminal motoneurons (TMNs). In voltage clamp, 10 microM serotonin (5-HT) induced a region of negative slope resistance (NSR) in the steady-state current-voltage (I-V) relationship at potentials less negative than -58 mV, creat...

BACKGROUND Rapid eye movement sleep (REMS) is characterized by activation of the cortical and hippocampal electroencephalogram (EEG) and atonia of non-respiratory muscles with superimposed phasic activity or twitching, particularly of cranial muscles such as those of the eye, tongue, face and jaw. While phasic activity is a characteristic feature of REMS, the neural substrates driving this acti...

The muscle contraction during voluntary movement is regulated by activities of α- and γ-motoneurons (αMNs and γMNs, respectively). The tension of jaw-closing muscles can be finely tuned over a wide range. This excellent function is likely to be achieved by the specific populations of αMNs innervating jaw-closing muscles. Indeed, we have recently demonstrated that in the rat dorsolateral trigemi...

Intracellular recordings from guinea pig trigeminal motoneurons (TMNs) in brain stem slices were used to determine the underlying ionic mechanisms responsible for our previously demonstrated enhancement of TMN excitability during jaw movements by serotonin (5-HT). 5-HT (0.5-100 microM) depolarized motoneurons and increased input resistance in the majority of neurons tested. Additionally, 5-HT r...

The thyroid hormones have profound effects on the development of neuromuscular system. These hormones exert their influence on both muscle fibers and related motoneurons during development. Masseter is one of the most important muscles for mastication in mammals. Thyroid hormone deficiency 3 weeks after birth, the period in which an alteration from sucking to biting occurs, could influence the ...

A previous study revealed that rostrodorsomedial oralis (Vo.r) neurons synapsing on trigeminal motoneurons use GABA and/or glycine as neurotransmitters. To determine the number and spatial distribution of contacts, injections of biotinamide and horseradish peroxidase were made into a Vo.r neuron and an alpha-motoneuron in the jaw-closing (JC) and jaw-opening (JO) motor nucleus, respectively, in...

The thyroid hormones have profound effects on the development of neuromuscular system. These hormones exert their influence on both muscle fibers and related motoneurons during development. Masseter is one of the most important muscles for mastication in mammals. Thyroid hormone deficiency 3 weeks after birth, the period in which an alteration from sucking to biting occurs, could influence the ...