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Neuroactive Steroid
Neurosteroids, also known as neuroactive steroids, are endogenous or exogenous steroids that rapidly alter neuronal excitability through interaction with ligand-gated ion channels and other cell surface receptors. The term ''neurosteroid'' was coined by the French physiologist Étienne-Émile Baulieu and refers to steroids synthesized in the brain. The term, ''neuroactive steroid'' refers to steroids that can be synthesized in the brain, or are synthesized by an endocrine gland, that then reach the brain through the bloodstream and have effects on brain function. The term neuroactive steroids was first coined in 1992 by Steven Paul and Robert Purdy. In addition to their actions on neuronal membrane receptors, some of these steroids may also exert effects on gene expression via nuclear steroid hormone receptors. Neurosteroids have a wide range of potential clinical applications from sedation to treatment of epilepsy and traumatic brain injury. Ganaxolone, a synthetic analog of the end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAA Receptor
The GABAA receptor (GABAAR) is an ionotropic receptor and ligand-gated ion channel. Its endogenous ligand is γ-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the central nervous system. Upon opening, the GABAA receptor on the postsynaptic cell is selectively permeable to chloride ions (Cl−) and, to a lesser extent, bicarbonate ions (HCO3−). Depending on the membrane potential and the ionic concentration difference, this can result in ionic fluxes across the pore. If the membrane potential is higher than the equilibrium potential (also known as the reversal potential) for chloride ions, when the receptor is activated Cl− will flow into the cell. This causes an inhibitory effect on neurotransmission by diminishing the chance of a successful action potential occurring at the postsynaptic cell. The reversal potential of the GABAA-mediated inhibitory postsynaptic potential (IPSP) in normal solution is −70 mV, contrasting the GABAB IPSP (-100 mV). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endogenous
Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, estradiol is an endogenous estrogen hormone produced within the body, whereas ethinylestradiol Ethinylestradiol (EE) is an estrogen medication which is used widely in birth control pills in combination with progestins. In the past, EE was widely used for various indications such as the treatment of menopausal symptoms, gynecological disord ... is an exogenous synthetic estrogen, commonly used in birth control pills. References External links *{{Wiktionary-inline, endogeny Biology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inhibitory Postsynaptic Potential
An inhibitory postsynaptic potential (IPSP) is a kind of synaptic potential that makes a postsynaptic neuron less likely to generate an action potential.Purves et al. Neuroscience. 4th ed. Sunderland (MA): Sinauer Associates, Incorporated; 2008. IPSP were first investigated in motorneurons by David P. C. Lloyd, John Eccles and Rodolfo Llinás in the 1950s and 1960s. The opposite of an inhibitory postsynaptic potential is an excitatory postsynaptic potential (EPSP), which is a synaptic potential that makes a postsynaptic neuron ''more'' likely to generate an action potential. IPSPs can take place at all chemical synapses, which use the secretion of neurotransmitters to create cell to cell signalling. Inhibitory presynaptic neurons release neurotransmitters that then bind to the postsynaptic receptors; this induces a change in the permeability of the postsynaptic neuronal membrane to particular ions. An electric current that changes the postsynaptic membrane potential to create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedative
A sedative or tranquilliser is a substance that induces sedation by reducing irritability or excitement. They are CNS depressants and interact with brain activity causing its deceleration. Various kinds of sedatives can be distinguished, but the majority of them affect the neurotransmitter gamma-aminobutyric acid (GABA). In spite of the fact that each sedative acts in its own way, most produce relaxing effects by increasing GABA activity. This group is related to hypnotics. The term ''sedative'' describes drugs that serve to calm or relieve anxiety, whereas the term ''hypnotic'' describes drugs whose main purpose is to initiate, sustain, or lengthen sleep. Because these two functions frequently overlap, and because drugs in this class generally produce dose-dependent effects (ranging from anxiolysis to loss of consciousness) they are often referred to collectively as ''sedative-hypnotic'' drugs. Sedatives can be used to produce an overly-calming effect ( alcohol being the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aphrodisiac
An aphrodisiac is a substance that increases sexual desire, sexual attraction, sexual pleasure, or sexual behavior. Substances range from a variety of plants, spices, foods, and synthetic chemicals. Natural aphrodisiacs like cannabis or cocaine are classified into plant-based and non-plant-based substances. There are non-naturally-occurring aphrodisiacs like MDMA and methamphetamine. Aphrodisiacs can be classified by their type of effects (i.e., psychological or physiological). Aphrodisiacs that contain hallucinogenic properties like Bufotenin have psychological effects on a person that can increase sexual desire and sexual pleasure. Aphrodisiacs that contain smooth muscle relaxing properties like yohimbine have physiological effects on a person that can affect hormone levels and increase blood flow. It is possible that the aphrodisiac effect of a substance is due to the placebo effect. Other substances that impede on areas that aphrodisiacs aim to enhance are classified as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serenic
A serenic, or antiaggressive agent, is a type of drug which reduces the capacity for irritability and aggression. Examples The recreational drug MDMA ("ecstasy") and a variety of related drugs have been described as ''empathogen-entactogens'', or simply as ''entactogens''. These agents possess serenic and empathy-increasing properties in addition to their euphoriant effects, and have been associated with increased sociability, friendliness, and feelings of closeness to others as well as emotional empathy and prosocial behavior. The entactogenic effects of these drugs are thought to be related to their ability to temporarily increase the levels of certain brain chemicals, including serotonin, dopamine, and, particularly, oxytocin. Certain other serotonergic drugs, such as 5-HT1A receptor, 5-HT1A receptor agonists, also increase oxytocin levels and may possess serenic properties as well. The phenylpiperazine mixed 5-HT1A and 5-HT1B receptor, 5-HT1B receptor agonists eltoprazine, flup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prosocial Behavior
Prosocial behavior, or intent to benefit others, is a social behavior that "benefit[s] other people or society as a whole", "such as helping, sharing, donating, co-operating, and volunteering". Obeying the rules and conforming to socially accepted behaviors (such as stopping at a "Stop" sign or paying for groceries) are also regarded as prosocial behaviors. These actions may be motivated by empathy and by concern about the welfare and rights of others,Sanstock, John W. A Topical Approach to Life Span Development 4th Ed. New York: McGraw-Hill, 2007. Ch. 15, pp. 489–491 as well as for egoistic or practical concerns, such as one's social status or reputation, hope for direct or indirect reciprocity, or adherence to one's perceived system of fairness. It may also be motivated by altruism, though the existence of pure altruism is somewhat disputed, and some have argued that this falls into philosophical rather than psychological realm of debate. Evidence suggests that pro sociality is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleasure
Pleasure refers to experience that feels good, that involves the enjoyment of something. It contrasts with pain or suffering, which are forms of feeling bad. It is closely related to value, desire and action: humans and other conscious animals find pleasure enjoyable, positive or worthy of seeking. A great variety of activities may be experienced as pleasurable, like eating, having sex, listening to music or playing games. Pleasure is part of various other mental states such as ecstasy, euphoria and flow. Happiness and well-being are closely related to pleasure but not identical with it. There is no general agreement as to whether pleasure should be understood as a sensation, a quality of experiences, an attitude to experiences or otherwise. Pleasure plays a central role in the family of philosophical theories known as hedonism. Overview "Pleasure" refers to experience that feels good, that involves the enjoyment of something. The term is primarily used in association wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stress (psychological)
In psychology, stress is a feeling of emotional strain and pressure. Stress is a type of psychological pain. Small amounts of stress may be beneficial, as it can improve athletic performance, motivation and reaction to the environment. Excessive amounts of stress, however, can increase the risk of strokes, heart attacks, ulcers, and mental illnesses such as depression and also aggravation of a pre-existing condition. Stress can be external and related to the environment, but may also be caused by internal perceptions that cause an individual to experience anxiety or other negative emotions surrounding a situation, such as pressure, discomfort, etc., which they then deem stressful. Hans Selye (1974) proposed four variations of stress. On one axis he locates good stress (eustress) and bad stress (distress). On the other is over-stress (hyperstress) and understress (hypostress). Selye advocates balancing these: the ultimate goal would be to balance hyperstress and hypostres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anxiolytic
An anxiolytic (; also antipanic or antianxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxiety disorders and their related psychological and physical symptoms. Nature of anxiety Anxiety is a naturally-occurring emotion and an innate response of the body to the environmental stimuli. Mild to moderate anxiety would increase level of performance. However, when anxiety levels exceed the tolerability of a person, anxiety disorders may occur. People with anxiety disorders can exhibit fear responses such as defensive behaviors, high levels of alertness and negative emotions, without external stimuli which induce anxiety within an individual. Those with anxiety disorders are also often found to have concurrent psychological disorders, most commonly depression. Anxiety disorders are divided into 6 types in clinical recognition. They are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antidepressant
Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, headaches, sexual dysfunction, and emotional blunting. There is a slight increased risk of suicidal thinking and behavior when taken by children, adolescents, and young adults. Discontinuation syndrome may occur after stopping any antidepressant which resembles recurrent depression. Some research regarding the effectiveness of antidepressants for depression in adults has found benefits, whilst other research has not. Evidence of benefit in children and adolescents is unclear. The twenty-one most commonly prescribed antidepressant medications are more effective than placebo for the short-term (acute) treatments of adults with major depressive disorder. There is debate in the medical community about how much of the observed effects of antidep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoform
A protein isoform, or "protein variant", is a member of a set of highly similar proteins that originate from a single gene or gene family and are the result of genetic differences. While many perform the same or similar biological roles, some isoforms have unique functions. A set of protein isoforms may be formed from alternative splicings, variable promoter usage, or other post-transcriptional modifications of a single gene; post-translational modifications are generally not considered. (For that, see Proteoforms.) Through RNA splicing mechanisms, mRNA has the ability to select different protein-coding segments ( exons) of a gene, or even different parts of exons from RNA to form different mRNA sequences. Each unique sequence produces a specific form of a protein. The discovery of isoforms could explain the discrepancy between the small number of protein coding regions genes revealed by the human genome project and the large diversity of proteins seen in an organism: different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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