Neural signaling

That is, the pressure is adjusted automatically in response to signals from various baroreceptors. Control of abnormally high pressure can, at least in theory, be achieved by interfering with the chain of transmission of the neural signals that lead to elevation of pressure. Initial success in control of hypertension was met with the ganglionic blocking agents which in effect in-... 

Photoreceptors in the eyes convert radiation in the visible band into neural signals that reach the brain. Photoreceptors are located throughout the retina, a sensoiy membrane that covers the entire back of the... 

AQP4 is the predominant water channel in the central nervous system (CNS), where it is involved in maintaining brain water balance and neural signal transduction. It is mainly expressed in astroglial cells, which support the neurons. Outside the CNS, AQP4 has been found in the basolateral membrane of renal principal cells as well as in various glandular epithelia, airways, skeletal muscle, stomach, retina and ear. 

Zheng J, Ghorpade A, Niemann D, Cotter RL, Thylin MR, Epstein L, Swartz JM, Shepard RB, Liu X, Nukuna A, Gendelman HE (1999a) Lymphotrofric virions affect chemokine receptor-mediated neural signaling and apoptosis implications for human immunodeficiency virus type 1-associated dementia. J Virol 73(10) 8256-8267... 

Sensation involves the conversion of physical energy into nerve impulses (e.g., photons are converted into neural signals for vision), but perception involves making a meaningful representation of those signals. This includes all sensory modalities vision (sight), audition (hearing). 

Epilepsy is an example of excessive neural signaling in the central nervous system. Relative cellular and extracellular space (ECS) volume has been demonstrated to play an important role in the propensity for epileptic seizures. For example, reducing ECS volume by exposure to hypotonic medium produces hyperexcitability and enhanced epileptiform activity, whereas hyperosmolar medium reduces excitability. The hypothesis that AQP4-dependent water transport in astrocytes might modulate intrinsic brain excitability was tested by seizure susceptibility in response to the GABAa antagonist convulsant pentylenetetrazol... 

The occupancy of hormone receptors can fluctuate greatly and is ultimately determined by the concentration of free hormone in the blood. The major determinants of hormone concentrations are (1) the rate of hormone secretion from endocrine cells and (2) the rate of hormone removal by clearance or metabolic inactivation. As we have seen, most hormones (with the exception of steroids) are stored in secretory granules. When the hormone is needed, the granule membranes fuse with the plasma membrane to liberate their contents into the bloodstream. This event is triggered by signals from other hormones or by neural signals. Stimulation of hormonal secretion is usually coupled with an increase of hormone synthesis, so that hormonal stores are replenished. 

Hearing works by the ear detecting sound waves, converting them into neural signals and then sending the signals to the brain. The ear has three divisions the external ear, the middle ear, and the inner ear (Figure 10). The external ear collects sound waves and funnels them down the ear canal, where they vibrate the eardrum. Within the middle ear, the eardrum is connected to... 

Since the 1970s, nerve surrounding electrodes have become the most successful types of implantable biomedical electrodes in clinical use. For example, they have been used for stimulation of the lower limb [12], the urinary bladder [13], and for recording neural signals [14,15]. Some electrodes have been safely in use for over 15 years [16]. They have been investigated intensively and many efforts have been made in respect to spatial selectivity and nerve fiber recruitment. 

The neural inhibition of pheromone production has been implicated in several moths. In L. dispar, it is thought that the presence of sperm in the spermatheca results in a neural signal that is responsible for pheromonostasis (Giebultowicz et al., 1991). Demonstration that a signal sent via the VNC is regulating the... 

The gaseous free radical nitric oxide (NO), a non-conventional neural messenger, is synthesized in neurons by the enzyme nitric oxide synthase (NOS), which can be revealed in histological sections by NADPH-diaphorase histochemistry or NOS immunohisto-chemistry. The role of NO in neural signaling has raised considerable interest (see, for example, Schmidt and Walter, 1994), stemming also from the finding that NOS has a discrete distribution in subsets of brain neurons, including intense expression in neuronal subsets of the striatum (Vincent, 2000). 

Houk JC, Adams JL, Barto AG (1995) A model of how the basal ganglia generate and use neural signals that predict reinforcement. In Houk JC, Davis JL, Beiser DG (Eds), Models of Information Processing in the Basal Ganglia, pp. 249-270. MIT Press, Cambridge, Massachusetts. 

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