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Noradrenergic Cell Group Acg
Noradrenergic cell group Acg is a group of cells fluorescent for norepinephrine that are located in the central gray of the midbrain The midbrain or mesencephalon is the forward-most portion of the brainstem and is associated with vision, hearing, motor control, sleep and wakefulness, arousal ( alertness), and temperature regulation. The name comes from the Greek ''mesos'', " ... at the level of the trochlear nucleus in the squirrel monkey (Saimiri) and to a lesser degree in the macaque. References External links BrainInfo Norepinephrine {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noradrenergic Cell Groups
Noradrenergic cell groups refers to collections of neurons in the central nervous system that have been demonstrated by histochemical fluorescence to contain the neurotransmitter norepinephrine (noradrenalin). They are named * Noradrenergic cell group A1 * Noradrenergic cell group A2 * Noradrenergic cell group A4 * Noradrenergic cell group A5 * Noradrenergic cell group A6 * Noradrenergic cell group A7 *Noradrenergic cell group A6sc * Noradrenergic cell group Acg See also *Adrenergic cell groups Adrenergic cell groups refers to collections of neurons in the central nervous system that stain for PNMT, the enzyme that converts norepinephrine to epinephrine (adrenaline). Thus, it is postulated that the neurotransmitter they produce may be ep ... References External links * More information aBrainInfo Norepinephrine {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Gray
The periaqueductal gray (PAG, also known as the central gray) is a brain region that plays a critical role in autonomic function, motivated behavior and behavioural responses to threatening stimuli. PAG is also the primary control center for descending pain modulation. It has enkephalin-producing cells that suppress pain. The periaqueductal gray is the gray matter located around the cerebral aqueduct within the tegmentum of the midbrain. It projects to the nucleus raphe magnus, and also contains descending autonomic tracts. The ascending pain and temperature fibers of the spinothalamic tract send information to the PAG via the spinomesencephalic tract (so-named because the fibers originate in the spine and terminate in the PAG, in the mesencephalon or midbrain). This region has been used as the target for brain-stimulating implants in patients with chronic pain. Role in analgesia Stimulation of the periaqueductal gray matter of the midbrain activates enkephalin-releasing neur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Midbrain
The midbrain or mesencephalon is the forward-most portion of the brainstem and is associated with vision, hearing, motor control, sleep and wakefulness, arousal ( alertness), and temperature regulation. The name comes from the Greek ''mesos'', "middle", and ''enkephalos'', "brain". Structure The principal regions of the midbrain are the tectum, the cerebral aqueduct, tegmentum, and the cerebral peduncles. Rostrally the midbrain adjoins the diencephalon ( thalamus, hypothalamus, etc.), while caudally it adjoins the hindbrain (pons, medulla and cerebellum). In the rostral direction, the midbrain noticeably splays laterally. Sectioning of the midbrain is usually performed axially, at one of two levels – that of the superior colliculi, or that of the inferior colliculi. One common technique for remembering the structures of the midbrain involves visualizing these cross-sections (especially at the level of the superior colliculi) as the upside-down fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trochlear Nucleus
The nucleus of the trochlear nerve () is located in the midbrain, at an intercollicular level between the superior colliculus and inferior colliculus. It is a motor nucleus, and so is located near the midline, embedded within the medial longitudinal fasciculus (see diagram at right). The oculomotor nerve and trochlear nerve are the only two cranial nerves with nuclei in the midbrain, other than the trigeminal nerve, which has a midbrain nucleus called the mesencephalic nucleus of trigeminal nerve, which functions in preserving dentition. Oddly, fibers from the trochlear nucleus cross over in the trochlear decussation of the midbrain, located in the superior medullary velum to exit dorsally, the only cranial nerve to do so. The trochlear nerve then goes around the midbrain, and is visible coming out of the sides. See also * Trochlear nerve The trochlear nerve (), ( lit. ''pulley-like'' nerve) also known as the fourth cranial nerve, cranial nerve IV, or CN IV, is a cranial n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
