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Baroreceptor Reflex
The baroreflex or baroreceptor reflex is one of the body's homeostatic mechanisms that helps to maintain blood pressure at nearly constant levels. The baroreflex provides a rapid negative feedback loop in which an elevated blood pressure causes the heart rate to decrease. Decreased blood pressure decreases baroreflex activation and causes heart rate to increase and to restore blood pressure levels. Their function is to sense pressure changes by responding to change in the tension of the arterial wall. The baroreflex can begin to act in less than the duration of a cardiac cycle (fractions of a second) and thus baroreflex adjustments are key factors in dealing with postural hypotension, the tendency for blood pressure to decrease on standing due to gravity. The system relies on specialized neurons, known as baroreceptors, chiefly in the aortic arch and carotid sinuses, to monitor changes in blood pressure and relay them to the medulla oblongata. Baroreceptors are stretch rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2116 Baroreceptor Reflex Flow Art , synthetic chemical element with atomic number 116
{{Numberdis ...
116 (''one hundred and sixteen'') may refer to: *116 (number) *AD 116 *116 BC *116 (Devon and Cornwall) Engineer Regiment, Royal Engineers, a military unit *116 (MBTA bus) *116 (New Jersey bus) *116 (hip hop group), a Christian hip hop collective *116 emergency number, see List of emergency telephone numbers ** 116 emergency telephone number in California *116 helplines in Europe *Route 116, see list of highways numbered 116 * 116 Sirona, a main-belt asteroid See also * 11/6 (other) * *Livermorium Livermorium is a synthetic chemical element; it has symbol Lv and atomic number 116. It is an extremely radioactive element that has only been created in a laboratory setting and has not been observed in nature. The element is named after the La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atrium (heart)
The atrium (; : atria) is one of the two Heart#Chambers, upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the Ventricle (heart), heart ventricles through the atrioventricular valve, atrioventricular mitral valve, mitral and tricuspid valve, tricuspid heart valves. There are two atria in the human heart – the left atrium receives blood from the pulmonary circulation, and the right atrium receives blood from the venae cavae of the systemic circulation. During the cardiac cycle, the atria receive blood while relaxed in diastole, then contract in systole to move blood to the ventricles. Each atrium is roughly cube-shaped except for an ear-shaped projection called an atrial appendage, previously known as an auricle. All animals with a closed circulatory system have at least one atrium. The atrium was formerly called the 'auricle'. That term is still used to describe this chamber in some other animals, such as the ''Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baroreceptors
Baroreceptors (or archaically, pressoreceptors) are stretch receptors that sense blood pressure. Thus, increases in the pressure of blood vessel triggers increased action potential generation rates and provides information to the central nervous system. This sensory information is used primarily in autonomic reflexes that in turn influence the heart cardiac output and vascular smooth muscle to influence vascular resistance. Baroreceptors act immediately as part of a negative feedback system called the baroreflex as soon as there is a change from the usual mean arterial blood pressure, returning the pressure toward a normal level. These reflexes help regulate short-term blood pressure. The solitary nucleus in the medulla oblongata of the brain recognizes changes in the firing rate of action potentials from the baroreceptors, and influences cardiac output and systemic vascular resistance. Baroreceptors can be divided into two categories based on the type of blood vessel in which t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Nucleus Of Vagus Nerve
The dorsal nucleus of vagus nerve (or posterior nucleus of vagus nerve or dorsal vagal nucleus or nucleus dorsalis nervi vagi or nucleus posterior nervi vagi) is a cranial nerve nucleus of the vagus nerve (CN X) situated in the medulla oblongata of the brainstem ventral to the floor of the fourth ventricle. It contains nerve cell bodies of parasympathetic neurons of CN X that provide parasympathetic innervation to the gastrointestinal tract and lungs as well as other thoracic and abdominal organs. These functions include, among others, bronchoconstriction and gland secretion. Cell bodies of pre-ganglionic parasympathetic neurons of CN X that innervate the heart meanwhile reside in the nucleus ambiguus, and additional cell bodies of the nucleus ambiguus give rise to the branchial efferent motor fibers of the vagus nerve (CN X) terminating in the laryngeal, and pharyngeal muscles, and musculus uvulae muscle. Additional images File:Gray694.png, Section of the medulla oblongata at a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleus Ambiguus
The nucleus ambiguus ("ambiguous nucleus" in English) is a group of large motor neurons, situated deep in the medullary part of the reticular formation named by Jacob Clarke. The nucleus ambiguus contains the cell bodies of neurons that innervate the muscles of the soft palate, pharynx, and larynx which are associated with speech and swallowing. As well as motor neurons, the nucleus ambiguus contains preganglionic parasympathetic neurons which innervate postganglionic parasympathetic neurons in the heart.Machado, BH and Brody, MJ"Role MJ of the nucleus ambiguus in the regulation of heart rate and arterial pressure."/ref> It is a region of histologically disparate cells located just dorsal ( posterior) to the inferior olivary nucleus in the lateral portion of the upper (rostral) medulla. It receives upper motor neuron innervation directly via the corticobulbar tract. This nucleus gives rise to the branchial efferent motor fibers of the vagus nerve (CN X) terminating in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermediolateral Nucleus
The intermediolateral nucleus (IML) is located in Rexed lamina VII of the lateral grey column, one of three grey matter columns found in the spinal cord. The intermediolateral cell column exists at vertebral levels T1 – L3. It mediates the entire sympathetic innervation of the body, but the nucleus resides in the grey matter of the spinal cord. Rexed Lamina VII contains several well defined nuclei including the posterior thoracic nucleus (Clarke's column), the intermediolateral nucleus, and the sacral autonomic nucleus. It extends from T1 to L3, and contains the autonomic motor neurons that give rise to the preganglionic fibers of the sympathetic nervous system The sympathetic nervous system (SNS or SANS, sympathetic autonomic nervous system, to differentiate it from the somatic nervous system) is one of the three divisions of the autonomic nervous system, the others being the parasympathetic nervous sy ..., (preganglionic sympathetic general visceral efferents). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rostral Ventrolateral Medulla
The rostral ventrolateral medulla (RVLM), also known as the pressor area of the medulla, is a part of the ventrolateral medulla in the brainstem responsible for basal and reflex control of sympathetic activity associated with cardiovascular function. Abnormally elevated sympathetic activity in the RVLM is associated with various cardiovascular diseases, such as heart failure and hypertension. The RVLM is notably involved in the baroreflex. It receives inhibitory GABAergic input from the caudal ventrolateral medulla (CVLM). The RVLM is a primary regulator of the sympathetic nervous system; it sends catecholaminergic projections to the sympathetic preganglionic neurons in the intermediolateral nucleus of the spinal cord via reticulospinal tract. Physostigmine, a choline-esterase inhibitor, elevates endogenous levels of acetylcholine and causes a rise in blood pressure by stimulation of the RVLM. Orexinergic neurons from the lateral hypothalamus The lateral hypothalamus (L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABA
GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GABA is sold as a dietary supplement in many countries. It has been traditionally thought that exogenous GABA (i.e., taken as a supplement) does not cross the blood–brain barrier, but data obtained from more recent research (2010s) in rats describes the notion as being unclear. The carboxylate form of GABA is γ-aminobutyrate. Function Neurotransmitter Two general classes of GABA receptor are known: * GABAA in which the receptor is part of a ligand-gated ion channel complex * GABAB metabotropic receptors, which are G protein-coupled receptors that open or close ion channels via intermediaries (G proteins) Neurons that produce GABA as their output are called GABAergic neurons, and have chiefly inhibitory action at receptors in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caudal Ventrolateral Medulla
The ventrolateral medulla, part of the medulla oblongata of the brainstem, plays a major role in regulating arterial blood pressure and breathing. It regulates blood pressure by regulating the activity of the sympathetic nerves that target the heart and peripheral blood vessels. The ventrolateral medulla consists of a rostral ventrolateral medulla (RVLM) and a caudal ventrolateral medulla (CVLM). Neurons in the RVLM project directly to preganglionic neurons in the spinal cord and maintain tonic activity in the sympathetic vasomotor nerves. This activity is inhibited by GABA GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GA ... output from the CVLM. References Sympathetic nervous system Reflexes Medulla oblongata Cardiovascular physiology {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solitary Nucleus
The solitary nucleus (SN) (nucleus of the solitary tract, nucleus solitarius, or nucleus tractus solitarii) is a series of neurons whose cell bodies form a roughly vertical column of grey matter in the medulla oblongata of the brainstem. Their axons form the bulk of the enclosed solitary tract. The solitary nucleus can be divided into different parts including dorsomedial, dorsolateral, and ventrolateral subnuclei. The solitary nucleus receives general visceral and special visceral inputs from the facial nerve (CN VII), glossopharyngeal nerve (CN IX) and vagus nerve (CN X); it receives and relays stimuli related to taste and visceral sensation. It sends outputs to various parts of the brain, such as the hypothalamus, thalamus, and reticular formation, forming circuits that contribute to autonomic regulation. Cells along the length of the SN are arranged roughly in accordance with function; for instance, cells involved in taste are located in the rostral part, while those rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamatergic
Glutamatergic means "related to glutamate". A glutamatergic agent (or drug) is a chemical that directly modulates the excitatory amino acid (glutamate/aspartate) system in the body or brain. Examples include excitatory amino acid receptor agonists, excitatory amino acid receptor antagonists, and excitatory amino acid reuptake inhibitors. See also * Adenosinergic * Adrenergic * Cannabinoidergic * Cholinergic * Dopaminergic Dopaminergic means "related to dopamine" (literally, "working on dopamine"), a common neurotransmitter. Dopaminergic substances or actions increase dopamine-related activity in the brain. Dopaminergic pathways, Dopaminergic brain pathways facil ... * GABAergic * GHBergic * Glycinergic * Histaminergic * Melatonergic * Monoaminergic * Opioidergic * Serotonergic * Sigmaergic References Neurochemistry Neurotransmitters {{nervous-system-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vagus Nerve
The vagus nerve, also known as the tenth cranial nerve (CN X), plays a crucial role in the autonomic nervous system, which is responsible for regulating involuntary functions within the human body. This nerve carries both sensory and motor fibers and serves as a major pathway that connects the brain to various organs, including the heart, lungs, and digestive tract. As a key part of the parasympathetic nervous system, the vagus nerve helps regulate essential involuntary functions like heart rate, breathing, and digestion. By controlling these processes, the vagus nerve contributes to the body's "rest and digest" response, helping to calm the body after stress, lower heart rate, improve digestion, and maintain homeostasis. The vagus nerve consists of two branches: the right and left vagus nerves. In the neck, the right vagus nerve contains approximately 105,000 fibers, while the left vagus nerve has about 87,000 fibers, according to one source. However, other sources report sl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
