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Tetrad Test
The tetrad test is a series of behavioral paradigms in which rodents treated with cannabinoids such as THC show effects. It is widely used for screening drugs that induce cannabinoid receptor-mediated effects in rodents. The four behavioral components of the tetrad are spontaneous activity, catalepsy, hypothermia, and analgesia. Common assays for these behavioral paradigms are as follows: * Spontaneous activity (or hypomotility) is determined by an open field test, in which a mouse is placed in a cage with perpendicular grid lines, usually spaced by approx. 1 inch. An experimenter counts the number of line crossings by the mouse in a given amount of time. * Catalepsy is determined by the bar test. The mouse is placed on a bar oriented parallel to and approximately 1 inch off of the ground. If the mouse remains immobile on the bar for typically more than 20 seconds, it is considered cataleptic. * Hypothermia (reduced body temperature) is determined by using a rectal probe to measu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cannabinoids
Cannabinoids () are several structural classes of compounds found in the cannabis plant primarily and most animal organisms (although insects lack such receptors) or as synthetic compounds. The most notable cannabinoid is the phytocannabinoid tetrahydrocannabinol (THC) (delta-9-THC), the primary intoxicating compound in cannabis. Cannabidiol (CBD) is a major constituent of temperate Cannabis plants and a minor constituent in tropical varieties. At least 113 distinct phytocannabinoids have been isolated from cannabis, although only four (i.e., THCA, CBDA, CBCA and their common precursor CBGA) have been demonstrated to have a biogenetic origin. It was reported in 2020 that phytocannabinoids can be found in other plants such as rhododendron, licorice and liverwort, and earlier in Echinacea. Phytocannabinoids are multi-ring phenolic compounds structurally related to THC, but endocannabinoids are fatty acid derivatives. Nonclassical synthetic cannabinoids (cannabimimetics) include amin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marijuana
Cannabis, also known as marijuana among other names, is a psychoactive drug from the cannabis plant. Native to Central or South Asia, the cannabis plant has been used as a drug for both recreational and entheogenic purposes and in various traditional medicines for centuries. Tetrahydrocannabinol (THC) is the main psychoactive component of cannabis, which is one of the 483 known compounds in the plant, including at least 65 other cannabinoids, such as cannabidiol (CBD). Cannabis can be used by smoking, vaporizing, within food, or as an extract. Cannabis has various mental and physical effects, which include euphoria, altered states of mind and sense of time, difficulty concentrating, impaired short-term memory, impaired body movement (balance and fine psychomotor control), relaxation, and an increase in appetite. Onset of effects is felt within minutes when smoked, but may take up to 90 minutes when eaten. The effects last for two to six hours, depending on the amount us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Behavioral Concepts
Behavior (American English) or behaviour (British English) is the range of actions and mannerisms made by individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as well as the inanimate physical environment. It is the computed response of the system or organism to various stimuli or inputs, whether internal or external, conscious or subconscious, overt or covert, and voluntary or involuntary. Taking a behavior informatics perspective, a behavior consists of actor, operation, interactions, and their properties. This can be represented as a behavior vector. Models Biology Although disagreement exists as to how to precisely define behavior in a biological context, one common interpretation based on a meta-analysis of scientific literature states that "behavior is the internally coordinated responses (actions or inactions) of whole living organisms (individuals or groups) to internal and/or external stim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cannabinoid Receptor Type 2
The cannabinoid receptor type 2, abbreviated as CB2, is a G protein-coupled receptor from the cannabinoid receptor family that in humans is encoded by the ''CNR2'' gene. It is closely related to the cannabinoid receptor type 1 (CB1), which is largely responsible for the efficacy of endocannabinoid-mediated presynaptic-inhibition, the psychoactive properties of tetrahydrocannabinol (THC), the active agent in cannabis, and other phytocannabinoids (plant cannabinoids). The principal endogenous ligand for the CB2 receptor is 2-Arachidonoylglycerol (2-AG). CB2 was cloned in 1993 by a research group from Cambridge looking for a second cannabinoid receptor that could explain the pharmacological properties of tetrahydrocannabinol. The receptor was identified among cDNAs based on its similarity in amino-acid sequence to the cannabinoid receptor type 1 (CB1) receptor, discovered in 1990. The discovery of this receptor helped provide a molecular explanation for the established effects of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rimonabant
Rimonabant (also known as SR141716; trade names Acomplia, Zimulti) is an anorectic antiobesity drug that was first approved in Europe in 2006 but was withdrawn worldwide in 2008 due to serious psychiatric side effects; it was never approved in the United States. Rimonabant is an inverse agonist for the cannabinoid receptor CB1 and was the first drug approved in that class. History Rimonabant is a selective CB1 receptor blocker and was discovered and developed by Sanofi-Aventis; On 21 June 2006, the European Commission approved the sale of rimonabant in the then-25-member European Union as a prescription drug for use in conjunction with diet and exercise for patients with a body mass index (BMI) greater than 30 kg/m2, or patients with a BMI greater than 27 kg/m2 with associated risk factors, such as type 2 diabetes or dyslipidaemia. FroEMA index page/ref> It was first in its class to be approved anywhere in the world. Rimonabant was submitted to the Food and Dr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inverse Agonist
In pharmacology, an inverse agonist is a drug that binds to the same receptor as an agonist but induces a pharmacological response opposite to that of the agonist. A neutral antagonist has no activity in the absence of an agonist or inverse agonist but can block the activity of either. Inverse agonists have opposite actions to those of agonists but the effects of both of these can be blocked by antagonists. A prerequisite for an inverse agonist response is that the receptor must have a constitutive (also known as intrinsic or basal) level of activity in the absence of any ligand. An agonist increases the activity of a receptor above its basal level, whereas an inverse agonist decreases the activity below the basal level. The efficacy of a full agonist is by definition 100%, a neutral antagonist has 0% efficacy, and an inverse agonist has < 0% (i.e., negative) efficacy. Examples Receptors for which inverse agonists have been identified include the[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptor Antagonist
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of receptor proteins.Pharmacology Guide: In vitro pharmacology: concentration-response curves " '' GlaxoWellcome.'' Retrieved on December 6, 2007. They are sometimes called blockers; examples include alpha blockers, |
WIN 55,212-2
WIN 55,212-2 is a chemical described as an aminoalkylindole derivative, which produces effects similar to those of cannabinoids such as tetrahydrocannabinol (THC) but has an entirely different chemical structure. WIN 55,212-2 is a potent cannabinoid receptor agonist that has been found to be a potent analgesic in a rat model of neuropathic pain. It activates p42 and p44 MAP kinase via receptor-mediated signaling. At 5 μM WIN 55,212-2 inhibits ATP production in sperm in a CB1 receptor-dependent fashion. WIN 55,212-2, along with HU-210 and JWH-133, may prevent the inflammation caused by amyloid beta proteins involved in Alzheimer's disease, in addition to preventing cognitive impairment and loss of neuronal markers. This anti-inflammatory action is induced through agonist action at cannabinoid receptors, which prevents microglial activation that elicits the inflammation. WIN 55,212-2 is a full agonist at the CB1 cannabinoid receptor ( ''K''i = 1.9 nM) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agonist
An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the agonist, while an inverse agonist causes an action opposite to that of the agonist. Etymology From the Greek αγωνιστής (agōnistēs), contestant; champion; rival < αγων (agōn), contest, combat; exertion, struggle < αγω (agō), I lead, lead towards, conduct; drive Types of agonists can be activated by either endogenous agonists (such as |
Cannabinoid Receptor
Cannabinoid receptors, located throughout the body, are part of the endocannabinoid system a class of cell membrane receptors in the G protein-coupled receptor superfamily. As is typical of G protein-coupled receptors, the cannabinoid receptors contain seven transmembrane spanning domains. Cannabinoid receptors are activated by three major groups of ligands: endocannabinoids; plant cannabinoids (such as Tetrahydrocannabinol, produced by the cannabis plant); and synthetic cannabinoids (such as HU-210). All of the endocannabinoids and phytocannabinoids (plant based cannabinoids) are lipophilic. There are two known subtypes of cannabinoid receptors, termed CB1 and CB2. The CB1 receptor is expressed mainly in the brain (central nervous system or "CNS"), but also in the lungs, liver and kidneys. The CB2 receptor is expressed mainly in the immune system, in hematopoietic cells, and in parts of the brain. The protein sequences of CB1 and CB2 receptors are about 44% similar. When ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cannabinoid Receptor 1
Cannabinoid receptor type 1 (CB1), also known as cannabinoid receptor 1, is a G protein-coupled cannabinoid receptor that in humans is encoded by the ''CNR1'' gene. The human CB1 receptor is expressed in the peripheral nervous system and central nervous system. It is activated by: endocannabinoids, a group of retrograde neurotransmitters that include anandamide and 2-arachidonoylglycerol (2-AG); plant phytocannabinoids, such as the compound THC which is an active ingredient of the psychoactive drug cannabis; and, synthetic analogs of THC. CB1 is antagonized by the phytocannabinoid tetrahydrocannabivarin (THCV). The primary endogenous agonist of the human CB1 receptor is anandamide. Structure The CB1 receptor shares the structure characteristic of all G-protein-coupled receptors, possessing seven transmembrane domains connected by three extracellular and three intracellular loops, an extracellular N-terminal tail, and an intracellular C-terminal tail. The receptor may exist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot Plate Test
The hot plate test is a test of the pain response in animals, similar to the tail flick test. Both hot plate and tail-flick methods are used generally for centrally acting analgesic, while peripherally acting drugs are ineffective in these tests but sensitive to acetic acid-induced writhing test. The hot plate test is used in basic pain research and in testing the effectiveness of analgesics by observing the reaction to pain caused by heat. It was proposed by Eddy and Leimbach in 1953. They used a behavioral model of nociception where behaviors such as jumping and hind paw-licking are elicited following a noxious thermal stimulus. Licking is a rapid response to painful thermal stimuli that is a direct indicator of nociceptive threshold. Jumping represents a more elaborated response, with a latency, and encompasses an emotional component of escaping. Procedure * A transparent glass cylinder is used to keep the animal on the heated surface of the plate. * The temperature of the ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
