The spinal serotoninergic projection from the raphe magnus has been shown to modulate nociceptive inputs, and activation of this projection mediates nicotine-elicited analgesia. Here, we investigate the interactions between cholinergic and serotoninergic systems in the spinal cord, by conducting serotonin [5-hydroxytryptamine (5-HT)] efflux experiments on mouse spinal slices. At least three spi...

Suppression of reactions to one noxious stimulus by a spatially distant noxious stimulus is termed heterotopic antinociception. In lightly anesthetized rats, a noxious visceral stimulus, colorectal distension (CRD), suppressed motor withdrawals but not blood pressure or heart rate changes evoked by noxious hindpaw heat. Microinjection of muscimol, a GABA(A) receptor agonist, into raphe magnus (...

BACKGROUND Recently emerging evidence indicates that endometriotic lesions are wounds undergoing repeated tissue injury and repair (ReTIAR), and platelets induce epithelial-mesenchymal transition (EMT), fibroblast-to-myofibroblast transdifferentiation (FMT), leading ultimately to fibrosis. Due to the commonality of cyclic bleeding as in endometriosis, adenomyotic lesions are also wounds that un...

Clinical observations have long indicated a vestibular influence on autonomic function. Neuroanatomical studies in the rabbit and in the cat have identified descending vestibulo-autonomic pathways from the caudal portion of the medial vestibular nucleus and the inferior vestibular nucleus to the dorsal motor nucleus of the vagus nerve, the nucleus of the solitary tract, and some brain stem medu...

The midbrain periaqueductal gray (PAG) has been shown to be a site where various manipulations induce pain suppression. Recent physiological evidence (Behbehani and Pert, 1984; Behbehani et al., 1987) suggests that neurotensin has pronounced physiological actions in PAG and effects pain suppression. We have performed immunohistochemical studies in order to determine the magnitude and distributi...

Axons in the adult CNS fail to regenerate after injury, and therefore recovery from spinal cord injury (SCI) is limited. Although full recovery is rare, a modest degree of spontaneous recovery is observed consistently in a broad range of clinical and nonclinical situations. To define the mechanisms mediating spontaneous recovery of function after incomplete SCI, we created bilaterally complete ...

The antinociceptive and cardiovascular effects of midbrain periaqueductal gray (PAG) stimulation are mediated through a relay in the pontomedullary raphe magnus (RM) and adjacent nucleus reticularis magnocellularis (NRMC). To test whether the neurons important in mediating PAG-evoked effects are SEROTONERGIC, the responses of pontomedullary SEROTONERGIC-LIKE cells to PAG stimulation were tested...

Previous studies have identified two neurectoderm-specific serotonin binding proteins (SBP), one with an apparent Mr of 45 kDa, and one of 56 kDa. The current experiments were undertaken to test the hypothesis that these proteins are specific components of serotonergic neurons. Since actin has been found to bind serotonin, the relationship of the 2 forms of SBP to actin was also investigated. A...

Serotonin (5-HT) exerts excitatory effects in many brainstem regions involved in autonomic, somatic, motor, and sensory functions, and in control of vigilance. To determine the potential role of 5-HT2A receptors in these effects, we immunohistochemically mapped the distribution of 5-HT2A receptor-like protein in the rat pontomedullary brainstem. Areas containing the densest labeling included th...