Involvement of spinal α2 -adrenoceptors in prolonged modulation of hind limb withdrawal reflexes following acute noxious stimulation in the anaesthetized rabbit
Abstract
The role of spinal α2 -adrenoceptors in mediating long-lasting modulation of hind limb withdrawal reflexes following acute noxious chemical stimulation of distant heterotopic and local homotopic locations has been investigated in pentobarbitone-anaesthetized rabbits. Reflexes evoked in the ankle extensor muscle medial gastrocnemius (MG) by electrical stimulation of the ipsilateral heel, and reflexes elicited in the ankle flexor tibialis anterior and the knee flexor semitendinosus by stimulation at the base of the ipsilateral toes, could be inhibited for over 1 h after mustard oil (20%) was applied to either the snout or into the contralateral MG. The heel-MG response was also inhibited after applying mustard oil across the plantar metatarsophalangeal joints of the ipsilateral foot, whereas this homotopic stimulus facilitated both flexor responses. Mustard oil also caused a significant pressor effect when applied to any of the three test sites. The selective α2 -adrenoceptor antagonist, RX 821002 (100-300 μg, intrathecally), had no effect on reflexes per se, but did cause a decrease in mean arterial blood pressure. In the presence of the α2 -blocker, inhibitory and facilitatory effects of mustard oil on reflexes were completely ...Continue Reading
References
Diffuse noxious inhibitory controls (DNIC). I. Effects on dorsal horn convergent neurones in the rat
Involvement of the subnucleus reticularis dorsalis in diffuse noxious inhibitory controls in the rat
Effects of lesions of locus coeruleus/subcoeruleus on diffuse noxious inhibitory controls in the rat
Dynamic receptive field plasticity in rat spinal cord dorsal horn following C-primary afferent input
Behavioral model for diffuse noxious inhibitory controls (DNIC): potentiation by 5-hydroxytryptophan
Citations
Software Mentioned
Related Concepts
Related Feeds
Adrenergic Receptors: Trafficking
Adrenergic receptor trafficking is an active physiological process where adrenergic receptors are relocated from one region of the cell to another or from one type of cell to another. Discover the latest research on adrenergic receptor trafficking here.
Allergy and Asthma
Allergy and asthma are inflammatory disorders that are triggered by the activation of an allergen-specific regulatory t cell. These t cells become activated when allergens are recognized by allergen-presenting cells. Here is the latest research on allergy and asthma.