Limbic systems

OT receptors are localized ia the brain hypothalamus, limbic system, cortex, striatum, olfactory system, and brain stem. In the periphery, OT is best known for its stimulation of uterine smooth muscle and the milk ejection reflex. Thr , Om ]oxytocin(l—8),... 

The vomeronasal organ (VNO), located in the nose, is a small chemical sensing stmcture associated with odors and behavioral effects. The vomeronasal system, which is made up of the VNO and a portion of the brain s limbic system, is stmcturaHy independent of the olfactory and nervous terminalis systems in the nose. It may, however, interact with these systems in a manner dependent on prior experience or learning, and therefore be direcdy related to the association of smells and experiences. This independent chemosensory system in the nose may prove to open doors to new learning associated with the sense of smell and human behavior. 

The nucleus accumbens is part of the limbic system. It receives dopaminergic input through the mesolimbic system that originates from cell bodies in the ventral segmental area (A 10 cell group). This mesolimbic dopaminergic pathway is part of the reward pathways. Drugs of abuse (cocaine, amphetamine, opiates or nicotine) have been shown to increase the level of dopamine release in these neurons. 

Grace AA (2001) Psychostimulant actions on dopamine and limbic system function relevance to the pathophysiology and treatment of ADHD. In Solanto MV, Arnsten AFT, Castellanos FX (eds) Stimulant drugs and ADHD, Oxford University Press, pp 134—157... 

Mogenson, G, Jones, D and Yim, CY (1980) From motivation to action functional interface between the limbic system and the motor system. Progr. Neurobiol. 14 69-97. 

Much remains to be learned about the neurochemical regulation of noradrenergic transmission and even more research is required before we can define the role(s) of this neurotransmitter in the brain. Nevertheless, it is evident that these neurons are a crucial component of the network of monoamine influences on the limbic system and that they... 

The mechanism by which 5-HT2 antagonism could ameliorate schizophrenic symptoms and what effect 5-HT has on mesolimbic and mesocortical pathways through A10 neurons is even less certain. It is more likely that 5-HT s action occurs postsynaptically in the limbic system or PFC. The probability that neuroleptics benefit from a particular balance of DA and 5-HT2A antagonism is developed later. 

On this evidence one can confidently equate EPS with neuroleptic DA receptor (D2) antagonism in the striatum and possibly a reduction in the positive symptoms of schizophrenia through similar action in the limbic system (nucleus accumbens). 

ANSWER We have not looked in the spinal cord at all for substance P. Everything has been in the extrapyramidal and limbic systems. 

The direct link between the nose and the reproductive system has been called a non-cognitive bridge (Stoddart, 1990). A part of VN projection is non-olfactory and reaches the limbic system via a direct and monosynaptic relay (Larriva-Sahd et al., 1993 and 1994 Matsumoto et al., 1994). In addition to the production of the peripheral olfactory cells (Sec. 4.1 above), the placode also gives rise to a group of important... 

Benzodiazepines, especially lorazepam, are used to prevent and treat CINV.5,10 Lorazepam is thought to prevent input from the cerebral cortex and limbic system from reaching the central vomiting center in the brain stem.10 Sedation and amnesia are common side effects. Respiratory depression can occur with high doses or when other central depressants such as alcohol are combined with benzodiazepines. 

The serotonin 6 (5-HT6) receptor is one of the most recently studied serotonin receptors, and an important candidate gene for the study of MDD because it is abundant in the limbic system and some antidepressants have a high affinity for it (Monsma, Shen, Ward etal, 1993). 

In the first of these studies, the researchers identified the areas of the brain that are associated with normal sadness. They asked volunteer subjects to think about some very sad personal experiences - and about some emotionally neutral experiences - while their brains were being imaged in a PET scanner. When thinking about the sad experiences, the volunteers reported feeling intense sadness, and many of them became tearful. The PET scans showed the changes in brain activity that accompanied these sad feelings. They demonstrated increased blood flow in the limbic system - a part of the brain that is involved in the control of emotion - and decreased blood flow in parts of the brain that are involved in the control of attention. 

Figure 8.1 The pain pathway. The pain signal is transmitted to several regions of the brain, including the thalamus reticular formation hypothalamus limbic system and somatosensory cortex. Each region carries out a specific aspect of the response to pain.

Nerve signals from the thalamus and the reticular formation are transmitted to the limbic system as well as the hypothalamus. Together, these regions of the brain are responsible for behavioral and emotional responses to pain. The limbic system, in particular, may be involved with the mood-altering and attention-narrowing effect of pain. 

Endorphins are found primarily in the limbic system, hypothalamus, and brainstem. Enkephalins and dynorphin (in smaller quantities) are found primarily in the periaqueductal gray matter (PAG) of the midbrain, the limbic system, and the hypothalamus. These endogenous substances mimic the effects of morphine and other opiate drugs at many points in the analgesic system, including in the dorsal horns of the spinal cord. 

Fadda P., Martellotta M. C., De Montis M. G., Gessa G. L., Fratta W. (1992). Dopamine D1 and opioid receptor binding changes in the limbic system of sleep deprived rats. Neurochem. Int. 20 (Suppl.), 153S-156S. 

Zeitzer J., Lopez-Rodriguez F., Behnke E. et al. (2001). Serotonin and dopamine in the human cortex and limbic system during a 40h sleep deprivation challenge. Sleep 24, A76. 

Effects of NMDA channel blockade and increased limbic system metabolism on subsequent sleep... 

Limbic system amygdala (central, anterior, medial, and basolateral nuclei), medial and lateral septal nuclei medial septal nucleus... 

Olfactory system olfactory bulb Limbic system... 

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