Neural processing in the brain controls behavior through descending neurons (DNs) - neurons which carry signals from the brain to the spinal cord (or thoracic ganglia in insects). Because DNs arise from multiple circuits in the brain, the numerical simplicity and availability of genetic tools make Drosophila a tractable model for understanding descending motor control. As a first step towards a...

See "Ondansetron pretreatment reduces pain on injection of propofol" by Zahedi H, Maleki A, Rostami G on pages 239-243 (1). 5-HT3 receptors occur on various components of the pain modulation system. Expressed on peripheral nerve endings and autonomic afferents as well as in the monoaminergic descending inhibitory system and certain brain regions, 5-HT3 receptors play an indispensable role in sp...

The aims of the study were twofold: (1) to verify the hypothesis that neurons in the fastigial nucleus excite and inhibit hindlimb alpha-motoneurons and (2) to determine both the supraspinal and spinal relays of these actions. Axons of fastigial neurons were stimulated at the level of their decussation in the cerebellum, within the hook bundle of Russell, in deeply anesthetized cats with only t...

Projections from the nucleus incertus (NI) to the septum have been implicated in the modulation of hippocampal theta rhythm. In this study we describe a previously uncharacterized projection from the septum to the NI, which may provide feedback modulation of the ascending circuitry. Fluorogold injections into the NI resulted in retrograde labeling in the septum that was concentrated in the hori...

Spinal cord injury causes debilitating cardiovascular disturbances. The etiology of these disturbances remains obscure, partly because the locations of spinal cord pathways important for sympathetic control of cardiovascular function have not been thoroughly studied. To elucidate these pathways, we examined regions of the thoracic spinal cord important for reflex sympathetic control of arterial...

Activation and sensitization of trigeminovascular nociceptive pathways is believed to contribute to the neural substrate of the severe and throbbing nature of pain in migraine. Endocannabinoids, as well as being physiologically analgesic, are known to inhibit dural trigeminovascular nociceptive responses. They are also involved in the descending modulation of cutaneous-evoked C-fiber spinal noc...

It is widely assumed that learning results from alterations in the strength of synapses within the neural pathways that mediate a learned behavioral response and that these alterations are directly caused by training-induced activity of neurons connected by the changing synapses. Initial evidence for this view came from studies of habituation of defensive reflexes in several invertebrate specie...

T he burden of chronic pain to society is enormous. This is both in terms of physical and emotional impact to individuals and carers, in addition to the large financial burden. Current estimates suggest that 11.5–55.2% of individuals worldwide are defined as suffering from chronic widespread pain. A major characteristic of functional disorders such as irritable bowel syndrome (IBS) and inflamma...

The dendrites of spinal motoneurones are highly active, generating a strong persistent inward current (PIC) that has an enormous impact on processing of synaptic input. The PIC is subject to regulation by descending neuromodulatory systems releasing the monoamines serotonin and noradrenaline. At high monoaminergic drive levels, the PIC dominates synaptic integration, generating an intrinsic den...