{"id":254,"date":"2019-10-09T20:45:21","date_gmt":"2019-10-09T15:15:21","guid":{"rendered":"https:\/\/medicineplexus.com\/?p=254"},"modified":"2019-10-09T20:45:21","modified_gmt":"2019-10-09T15:15:21","slug":"cannabinoids","status":"publish","type":"post","link":"https:\/\/medicineplexus.com\/cannabinoids\/","title":{"rendered":"Cannabinoids"},"content":{"rendered":"\n<p><strong>Cannabinoids<\/strong><\/p>\n\n\n\n<ul><li><strong>Cannabis sativa, <\/strong>the hemp plant<strong>: Tetrahydrocannabinol (THC)<\/strong> is the main active principle of cannabis<\/li><li>The <strong>most abundant<\/strong> cannabinoids are <strong>THC,<\/strong> <\/li><li>its <strong>precursor cannabidiol, and cannabinol<\/strong>, a breakdown product formed spontaneously from THC <\/li><li>Cannabidiol and cannabinol <strong>lack the psychoactive properties of THC but can exhibit anticonvulsant activity.<\/strong><\/li><\/ul>\n\n\n\n<p>Three general types of\u00a0 cannabinoids: <\/p>\n\n\n\n<ul><li><strong>Endogenous&nbsp; cannabinoids <\/strong><strong><\/strong><\/li><li><strong>Herbal&nbsp; cannabinoids <\/strong><strong>\u00e0 <\/strong>present in the\nCannabis plant<\/li><li><strong>Synthetic cannabinoids <\/strong><strong><\/strong><\/li><\/ul>\n\n\n\n<p><strong>Cannabinoid\nreceptors<\/strong><\/p>\n\n\n\n<ul><li>Two types &#8211; <strong>CB1 receptors and CB2 receptors<\/strong><\/li><\/ul>\n\n\n\n<p><strong>Location<\/strong><\/p>\n\n\n\n<p><strong>CB1<\/strong> not homogeneously distributed, being\nconcentrated in the <\/p>\n\n\n\n<ul><li><strong>hippocampus<\/strong> (relevant to effects of\ncannabinoids on <strong>memory<\/strong>), <\/li><li><strong>cerebellum<\/strong> (relevant to loss of <strong>coordination<\/strong>), <\/li><li><strong>the hypothalamus <\/strong>(important in control\nof <strong>appetite and body temperature),<\/strong> <\/li><li><strong>substantia nigra, mesolimbic dopamine pathways<\/strong> \u00e0 implicated in psychological \u2018<strong>reward\u2019<\/strong><\/li><li><strong>the relative paucity<\/strong> of CB1 receptors in\nthe <strong>brain stem, consistent<\/strong> with the <strong>lack of serious depression of respiratory\nor cardiovascular function<\/strong> by cannabinoids.<\/li><\/ul>\n\n\n\n<p><strong>CB2 receptor<\/strong><\/p>\n\n\n\n<ul><li>located mainly in <strong>lymphoid tissue<\/strong> (spleen, tonsils, and thymus as well as circulating lymphocytes, monocytes, and tissue mast cells).<\/li><li>also present on <strong>microglia <\/strong>\u2013 immune cells in the CNS which when activated <strong>contribute to chronic pain<\/strong> <\/li><li>typical members of the family of <strong>G protein-coupled receptors<\/strong><\/li><\/ul>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"333\" height=\"386\" src=\"https:\/\/medicineplexus.com\/wp-content\/uploads\/2019\/10\/image-75.png?w=333\" alt=\"\" class=\"wp-image-255\" srcset=\"https:\/\/medicineplexus.com\/wp-content\/uploads\/2019\/10\/image-75.png 333w, https:\/\/medicineplexus.com\/wp-content\/uploads\/2019\/10\/image-75-259x300.png 259w\" sizes=\"(max-width: 333px) 100vw, 333px\" \/><\/figure><\/div>\n\n\n\n<ul><li>CB1 receptors are linked via\nGi\/o to inhibition of adenylyl cyclase and of voltage-operated calcium\nchannels, and to activation of G protein-sensitive inwardly rectifying potassium\n(GIRK) channels, causing membrane hyperpolarization. <\/li><\/ul>\n\n\n\n<ul><li>CB1 receptors are located in\nthe plasma membrane of nerve endings and inhibit transmitter release from\npresynaptic terminals, which is caused by depolarization and Ca2+ entry. <\/li><\/ul>\n\n\n\n<p><strong>PHARMACOLOGICAL\nEFFECTS<\/strong><\/p>\n\n\n\n<ul><li>Actions on the central nervous\nsystem include <strong>both depressant and\npsychotomimetic effects<\/strong><\/li><li><strong>A sensation of relaxation and well-being<\/strong>,\nsimilar to the effect of ethanol but <strong>without\nthe accompanying recklessness and aggression<\/strong>. <\/li><li>impairment of short-term memory\nand simple learning tasks <\/li><li>impairment of motor coordination\n(e.g. driving performance)<\/li><li>catalepsy \u2013 the adoption of\nfixed unnatural postures<\/li><li>hypothermia<\/li><li>analgesia<\/li><li>antiemetic action&nbsp; <\/li><li>increased appetite <\/li><li>reduction of intraocular\npressure<\/li><li>bronchodilatation.<\/li><\/ul>\n\n\n\n<p><strong>TOLERANCE AND DEPENDENCE<\/strong><\/p>\n\n\n\n<ul><li>Tolerance to cannabis and\nphysical dependence occur only to a minor degree and mainly in heavy users. <\/li><li>Cannabinoids are less liable\nthan opiates, nicotine or alcohol to cause dependence but may have long-term\npsychological effects.<\/li><\/ul>\n\n\n\n<p><strong>ENDOCANNABINOIDS<\/strong><\/p>\n\n\n\n<ul><li>Anandamide CB1 &gt; CB2<\/li><li>Virodhamine CB2 &gt; CB1<\/li><li>They are eicosanoid mediators<\/li><li>The main enzyme that\ninactivates anandamide is <strong>fatty acid\namide hydrolase (FAAH).<\/strong><\/li><li><strong>FAAH \u2018knockout\u2019 mice<\/strong> have <strong>an increased brain content of anandamide\nand an increased pain threshold;<\/strong> selective inhibitors of FAAH <strong>have analgesic and anxiolytic properties<\/strong>,\nimplicating endocannabinoids in nociception and anxiety<\/li><\/ul>\n\n\n\n<p><strong>SYNTHETIC\nCANNABINOIDS and their clinical application<\/strong><\/p>\n\n\n\n<ul><li>Cannabinoid receptor agonists\nwere developed in the 1970s in the hope that they would prove useful nonopioid\/\nnon-NSAID analgesics respectively, for limitations of opioids and NSAIDs), but\nadverse effects, particularly sedation and memory impairment, were problematic<\/li><\/ul>\n\n\n\n<ul><li><strong>Nabilone<\/strong>: sometimes used clinically for nausea and vomiting caused by cytotoxic chemotherapy if this is unresponsive to conventional antiemetics<\/li><\/ul>\n\n\n\n<ul><li>The first selective <strong>CB1 receptor antagonist, rimonabant <\/strong><strong>\u00e0 <\/strong>was licensed in Europe for treating\nobesity, <\/li><li>was withdrawn because it caused\n<strong>psychiatric problems including depression.<\/strong><\/li><\/ul>\n\n\n\n<ul><li>both the UK and the USA\ncannabinoids have been used as <strong>antiemetics<\/strong><\/li><\/ul>\n\n\n\n<ul><li>encourage <strong>weight gain in patients with chronic diseases such as HIV-AIDS and\nmalignancy<\/strong>. <\/li><\/ul>\n\n\n\n<ul><li><strong>Cannabis extract (Sativex)<\/strong> is used to treat <strong>spasticity in patients with multiple sclerosis<\/strong><\/li><\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"703\" height=\"197\" src=\"https:\/\/medicineplexus.com\/wp-content\/uploads\/2019\/10\/image-76.png?w=703\" alt=\"\" class=\"wp-image-256\" srcset=\"https:\/\/medicineplexus.com\/wp-content\/uploads\/2019\/10\/image-76.png 703w, https:\/\/medicineplexus.com\/wp-content\/uploads\/2019\/10\/image-76-300x84.png 300w\" sizes=\"(max-width: 703px) 100vw, 703px\" \/><\/figure>\n\n\n\n<p><strong>Cannabidiol<\/strong><\/p>\n\n\n\n<ul><li>Approved June 2018<\/li><li>specifically indicated for the\ntreatment of seizures associated with<strong>\nLennox Gastaut syndrome (LGS) or Dravet syndrome (DS) in patients 2 years of\nage and older.<\/strong><\/li><li>the anticonvulsant effect in\nhumans is unknown. <\/li><li>Cannabidiol <strong>DOES NOT<\/strong> appear to exert its\nanticonvulsant effects through interaction with cannabinoid receptors.<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Cannabinoids Cannabis sativa, the hemp plant: Tetrahydrocannabinol (THC) is the main active principle of cannabis The most abundant cannabinoids are THC, its precursor cannabidiol, and cannabinol, a breakdown product formed spontaneously from THC Cannabidiol and cannabinol lack the psychoactive properties of THC but can exhibit anticonvulsant activity. Three general types of\u00a0 cannabinoids: Endogenous&nbsp; cannabinoids Herbal&nbsp;[&#8230;]\n","protected":false},"author":3,"featured_media":255,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","footnotes":""},"categories":[3],"tags":[],"_links":{"self":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts\/254"}],"collection":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/comments?post=254"}],"version-history":[{"count":0,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts\/254\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/media\/255"}],"wp:attachment":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/media?parent=254"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/categories?post=254"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/tags?post=254"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}