Doczi MA, Morielli AD, Damon DH. Kv1.3 channels in postganglionic sympathetic neurons: expression, function, and modulation. Am J Physiol Regul Integr Comp Physiol 295: R733–R740, 2008. First published July 9, 2008; doi:10.1152/ajpregu.00077.2008.— Kv1.3 channels are known to modulate many aspects of neuronal function. We tested the hypothesis that Kv1.3 modulates the function of postganglionic...

It is well known that breathing introduces rhythmical oscillations in the heart rate and arterial pressure levels. Sympathetic oscillations coupled to the respiratory activity have been suggested as an important homeostatic mechanism optimizing tissue perfusion and blood gas uptake/delivery. This respiratory-sympathetic coupling is strengthened in conditions of blood gas challenges (hypoxia and...

Hyperinsulinemia increases sympathetic nerve activity and contributes to cardiovascular dysfunction in obesity and diabetes. Neurons of the hypothalamic paraventricular nucleus (PVN) regulate sympathetic nerve activity through mono- and poly-synaptic connections to preganglionic neurons in the spinal cord. The purpose of the present study was to determine whether PVN neurons mediate the sympath...

Hypertension is associated with enhanced cardiac sympathetic transmission, although the exact mechanisms underlying this are still unknown. We hypothesized that defective function of the norepinephrine uptake transporter (NET) may contribute to the sympathetic phenotype of the spontaneously hypertensive rat, and that this may occur before the development of hypertension itself. The dynamic kine...

The superior cervical ganglia (SCG) in rats are small, glossy, almond-shaped structures that contain sympathetic neurons. These neurons provide sympathetic innervations for the head and neck regions and they constitute a well-characterized and relatively homogeneous population (4). Sympathetic neurons are dependent on nerve growth factor (NGF) for survival, differentiation and axonal growth and...

Sympathetic neuronal apoptosis after nerve growth factor (NGF) deprivation requires the activation of two events: a protein synthesis-dependent, Bax-dependent release of mitochondrial cytochrome c and a protein synthesis-independent, Bax-independent development of competence. Unlike in most cells, cytosolic cytochrome c is not sufficient to induce cell death in NGF-maintained sympathetic neuron...

Sympathetic premotor neurons directly control sympathetic preganglionic neurons (SPNs) in the intermediolateral cell column (IML) of the thoracic spinal cord, and many of these premotor neurons are localized in the medulla oblongata. The rostral ventrolateral medulla contains premotor neurons controlling the cardiovascular conditions, whereas rostral medullary raphe regions are a candidate sour...

The relationship between the anatomy and neurochemistry of neurons in the ventral medulla oblongata in regions that is responsible for cardiovascular, airways, and respiratory regulation was investigated. Microinjections of excitant amino acid (glutamate, 100 nl, 100 mM) were made throughout the ventral medulla in anesthetized rats. Arterial blood pressure, sympathetic nerve activity and phreni...

When used at concentrations allowing interactions only with its high-affinity receptors, neurotrophin-3 (NT-3) promotes the survival of sensory neurons isolated from embryonic day 8 (E8) chicks, but not the survival of E11 sympathetic neurons. These sympathetic neurons (which can be rescued by the addition of NGF) display high-affinity receptors for NT-3 (Kd of 1.6 x 10(-11) M) that cannot be d...

During development, neurons are acutely dependent on target-derived trophic factors for survival. This dependence on trophic support decreases dramatically with maturation in several neuronal populations, including sympathetic neurons. Analyses of nerve growth factor deprivation in immature and mature sympathetic neurons indicate that maturation aborts the cell death pathway at a point that is ...