Adrenergic receptors | Alpha 2 | Pharmacology🩺

#drnajeeb #medicaleducation #medicines #alpha Adrenergic receptors | Alpha 2 | Pharmacology🩺 Like this video? Sign up now on our website at https://www.DrNajeebLectures.com to access 1000+ Exclusive videos on Basic Medical Sciences & Clinical Medicine. These are premium videos (NOT FROM YOUTUBE). All these videos come with English subtitles & download options. Sign up now! Get Lifetime Access for a one-time payment of $10 ONLY! Sign up now on our website at https://members.drnajeeblectures.com/ --------------------------------------------------------------------------------------------------------------------------- Why sign up for premium membership? Here's why! Membership Features for premium website members. 1. More than 1000+ Medical Lectures. 2. Basic Medical Sciences & Clinical Medicine. 3. Mobile-friendly interface with android and iOS apps. 4. English subtitles and new videos every week. 5. Download option for offline video playback. 6. Fanatic customer support and that's 24/7. 7. Fast video playback option to learn faster. 8. Trusted by over 2M+ students in 190 countries. --------------------------------------------------------------------------------------------------------------------------- ▬▬▬▬▬▬▬▬▬▬ Contents of this video ▬▬▬▬▬▬▬▬▬▬ 00:00:00 Start 00:01:27 Action on presynaptic alpha 2 receptors 00:02:48 Action on pancreas 00:04:35 Action on adipocytes 00:06:40 Platelets aggregation 00:07:32 Recap --------------------------------------------------------------------------------------------------------------------------- The α2 receptor couples to the Gi/o protein. It is a presynaptic receptor, causing negative feedback on, for example, norepinephrine (NE). When NE is released into the synapse, it feeds back on the α2 receptor, causing less NE release from the presynaptic neuron. This decreases the effect of NE. There are also α2 receptors on the nerve terminal membrane of the post-synaptic adrenergic neuron. Actions of the α2 receptor include: decreased insulin release from the pancreas increased glucagon release from the pancreas contraction of sphincters of the GI-tract negative feedback in the neuronal synapses - presynaptic inhibition of norepinephrine release in CNS decreased platelet aggregation decreases peripheral vascular resistance α2 agonists (see actions above) can be used to treat: hypertension – decrease blood pressure-raising actions of the sympathetic nervous system α2 antagonists can be used to treat: impotence – relax penile smooth muscles and ease blood flow depression – enhance mood by increasing norepinephrine secretion The adrenergic receptors or adrenoceptors are a class of G protein-coupled receptors that are targets of many catecholamines like norepinephrine (noradrenaline) and epinephrine (adrenaline) produced by the body, but also many medications like beta blockers, beta-2 (β2) agonists and alpha-2 (α2) agonists, which are used to treat high blood pressure and asthma, for example. Many cells have these receptors, and the binding of a catecholamine to the receptor will generally stimulate the sympathetic nervous system (SNS). The SNS is responsible for the fight-or-flight response, which is triggered by experiences such as exercise or fear-causing situations. This response dilates pupils, increases heart rate, mobilizes energy, and diverts blood flow from non-essential organs to skeletal muscle. These effects together tend to increase physical performance momentarily. --------------------------------------------------------------------------------------------------------------------------- Join this channel to get access to the perks: Sign up now on our website at https://members.drnajeeblectures.com/ Follow us on Facebook:-   / drnajeeb   Follow us on Instagram:-   / drnajeeblectures