Mechanisms stimulant activity

In the gastrointestinal tract, drugs or toxins, as well as mechanical stimulation, induce emesis by activation of sensory receptors on afferent neurons in the vagus and sympathetic nerves. Information is relayed to the vomiting centre via the nucleus tractus solitarius... 

Hydrogen ions accumulate in tissue damaged by inflammation and ischaemia and so pH is lowered. These protons may activate nociceptors directly via their own family of ion channels as well as sensitising them to mechanical stimulation. Acid-sensing ion channels (ASICS) are a family of sodium channels that are activated by protons — of special interest is one type found only in small dorsal root ganglion neurons that possibly are responsible for activation of nociceptors. Although the transduction of mechanical stimuli is poorly understood, ASICs are closely related to channels that respond to stretch. 

In atherosclerosis and other heart diseases, the role of carotenoids as antioxidants is probable, but for these types of diseases and also for other degenerative diseases such as cancers, non-antioxidant activities constitute other possible prevention mechanisms. These activities are, for example, stimulation of gap junction communications between cells, and the induction of detoxifying enzymes. The... 

The contribution by Rouzaud et al. teaches to apply a modified version of high resolution Transmission Electron Microscopy (TEM) as an efficient technique of quantitative investigation of the mechanism of irreversible capacity loss in various carbon candidates for application in lithium-ion batteries. The authors introduce the Corridor model , which is interesting and is likely to stimulate active discussion within the lithium-ion battery community. Besides carbon fibers coated with polycarbon (a candidate anode material for lithium-ion technology), authors study carbon aerogels, a known material for supercapacitor application. Besides the capability to form an efficient double electric layer in these aerogels, authors... 

Injured axons may develop spontaneous and repetitive firing known as ectopic activity. Injured primary afferents develop spontaneous action potential discharges that occur uncoupled from receptor stimulation in the periphery (Fig. 57-5). These ectopic discharges can be evoked by protons, cytokines or mechanical stimulation of the injured nerve. Another source of ectopic activity are pacemaker currents produced in the plasma membrane... 

In addition to being able to recognize the different cells involved in the acquired immune system of marine mammals, it is important to assure that the cells perform their functions appropriately. The ability of lymphocytes to proliferate upon stimulation (usually with mitogens) has been studied for several decades [1,12,14,15, 32-35], Recent advances include the demonstration of a conserved specificity for standard mitogens used in beluga whales [32] and harbor seals [33], An assay to assess the expression of the receptor for interleukin-2 (IL-2), an early event in lymphocyte activation, was adapted in harbor seals [35], bottlenose dolphins [36], and sea otters [37], Molecular and biochemical mechanisms of activation of beluga T lymphocytes do not vary substantially from those in other mammals [38],... 

R.aeymaek.ers Mechanical stimulation of cells in culture has been shown to release ATP which could diffuse to neighbouring cells and activate purinergic receptors. Can you exclude this possibility in the interpretation of your data ... 

A campus-wide mechanism for integration and coordination. The Institute for Sustainable Technology and Development at Georgia Tech serves in this capacity. The institute encourages activities in education and research and managing the campus and stimulates activities with other universities and industry. 

There is extensive evidence consistent with a role for CRH in mediating stress effects on memory consohdation. Activation of CRH receptors in the BLA by CRH released from the CEA facilitates stress effects on memory consohdation. Memory enhancement produced by CRH infusions in the hippocampus are blocked by propranolol, suggesting CRH, through a presynaptic mechanism, stimulates NE release in the hippocampus (Roozendaal et al. 2002). 

Mechanism of Action A sympathomimetic amine related to amphetamine and ephe-drine that enhances CNS stimulant activity. Peripheral actions include elevation of... 

Stimulation of NO synthase leads to activation of a NO-sensitive guanylyl cyclase. The associated increase in the cGMP level has multiple consequences. The cGMP can stimulate cGMP-dependent protein kinases it can also open cGMP-controUed ion channels. As a consequence, an increase in the intracellular Ca concentration takes place and a Ca signal is produced. NO can influence both protein phosphorylation and InsPs/diacylglycerol and Ca metabolism by this mechanism and activate a broad palette of biochemical reactions in the cell. 

D and E appear to stimulate the formation of 0 directly. The ability of A 23187 to elicit formation of O from PMNs 24,59,60,68.70) appears to be due to its action as an ionophore for Ca (see below). Other active stimuli include fluoride, notable because its effect is reversible human leucocyte pyrogen which might have a function in vivo and phorbol myristate acetate The latter has been very useful as a potent stimulus of the burst in various studies of the kinetics and mechanism of activation of the burst. 

Following inflammation there is a 10-fold increase in axons expressing AMPA or kainate receptors (Coggeshall and Carlton, 1999). In anaesthetized rats, antagonism of AMPA/kainate receptors inhibits dorsal horn neuronal responses induced by innocuous and noxious mechanical stimulation of a chronically inflamed ankle (Neugebauer et al., 1994). Application of kainate to the rat hindpaw induces activation of primary afferent neurons, an effect that is reduced by the AMPA/kainate antagonist DNQX (Ault and Hildebrand, 1993). 

Studies of Lsc in neutrophils also suggest that localization may play a role in activation of Rho (Francis et al., 2006). Immunostaining showed that Lsc was largely distributed uniformly on the plasma membrane. After 5 min of stimulation with W-formyl-methionyl-leucyl-phenylalanine (fMLP), the Lsc became enriched in the leading and trailing edges of the cells, sites of active cytoskeletal reorganization in these stimulated cells. While simple translocation to the plasma membranes does not appear to be a viable mechanism for activation in this case, localization within the membrane to direct activity to specific sites is indicated. 

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