eSagan 🇮🇳 @crackurbones@qoto.org
Joined Nov 2019
💊 We treat things by either imitating or blocking the post-ganglionic neurotransmitter.
💊 So, for instance, if we want to imitate a parasympathetic effect, we're going to give a drug that acts like acetylcholine, that acts like acetylcholine at muscarinic receptors.
💊 If we want to stop a parasympathetic effect, we're going to block a muscarinic receptor.
💊 So, things that act like a neurotransmitter are called agonists, and things that block the effects of neurotransmitters are called antagonists.
💊 Secretions are a very parasympathetic effect; we secrete stuff because we're going to go and try and digest stuff.
💊 And so, if we want to reduce secretions, we're going to try and block the effect of the muscarinic receptors. So, we're going to antagonize that muscarinic receptor.
💊 The group of drugs that we use, in general, to treat hypertension are called beta-blockers.
They're beta-blockers because they block the beta version of the adrenergic receptors (metabotropic receptors that receive information from norepinephrine are called adrenergic receptors).
💊 The drugs that act on the parasympathetic system either to mimic it or to block it, they stay peripheral.
💊 They have no effect on the brain other than an indirect effect.
They might make you feel dry, you'll get dry mouth, dry eyes, and that might make you, put you in a bad mood — but it's not a direct effect. They're not acting on the brain.
💊 In contrast, drugs that act on the sympathetic system tend to also have psychotropic effects, they also act in the central nervous system.
🔴 Autonomic Pharmacology: Adjusting the PS/S System
🔸 Instead of as in the skeletal motor system where there's one motor neuron that goes and enervates a skeletal muscle, autonomic systems get to the target by two neurons.
🔸 The first neuron sits in the central nervous system. We call it the preganglionic motor neuron, and it contacts a motor neuron that sits in an autonomic ganglion.
And in both the case of the parasymptathetic preganglionic and the sympathetic preganglionic — they're both using acetylcholine.
🔸 So, all motor neurons use acetylcholine. And all motor neurons going to the post-synaptic target — whether it's the skeletal muscle or whether it's a ganglion cell — is going to express a nicotinic acetylcholine receptor. This is a fast ionotropic receptor — it's going to very instantly give a response.
🔸 The sympathetic preganglionic neuron goes to a ganglionic neuron which expresses this nicotinic acetylcholine receptor.
🔸 The parasympathetic preganglionic also goes to a ganglionic neuron that expresses a nicotinic acetylcholine receptor. And there, the two systems diverge.
🔸 In the parasympathetic system, we stay with acetylcholine as our neurotransmitter. The ganglionic neuron sends a post-ganglionic axon, which is an unmyelinated axon that goes to one of the three targets — smooth muscle, cardiac muscle, or gland. And it is going to release acetylcholine.
🔸 There's a difference between the release of acetylcholine at the terminal of ganglionic neuron and the release of acetylcholine at the terminal of post-ganglionic axon.
And the difference is that the targets (e.g.: smooth muscle) are always expressing as metabotropic (very slow) indirect receptors.
🔸 They're acetylcholine receptors, but they're muscarinic, as opposed to nicotinic.
Each of these targets is going to express a different muscarinic receptor. The effect is that the transmission is slow.
🔸 Now, in the sympathetic system, once we get to the ganglion, we switch to norepinephrine (NE).
🔸 So, norepinephrine is contained in the ganglionic neurons, and they send an axon, and again, an unmyelinated post-ganglionic axon that enervates one of the three targets — smooth muscle, cardiac muscle, or gland.
🔸 These receptors that receive the message of norepinephrine are also metabotropic, and so therefore, they are also slow.
🖼️ Image source: Screen grab from https://www.coursera.org/learn/neurobiology/lecture/c8Tj0/autonomic-pharmacology-adjusting-the-ps-s-system
Indian scientists in Iran not been able to establish makeshift lab for COVID-19 test: Official sources
#India sending entire freakin labs with doctors to #iran to help it fight corona
https://www.reddit.com/r/IndiaSpeaks/comments/fjia9v/india_sending_entire_freakin_labs_with_doctors_to/
🦠 #COVID19
🇮🇳 https://twitter.com/IAF_MCC/status/1237257668055543808
🦠 The neuroinvasive potential of SARS‐CoV2 may be at least partially responsible for the respiratory failure of #COVID19 patients - Increasing evidence shows that #coronaviruses are not always confined to the respiratory tract and that they may also invade the central nervous system
https://onlinelibrary.wiley.com/doi/full/10.1002/jmv.25728
https://www.reddit.com/r/science/comments/fjfg05/the_neuroinvasive_potential_of_sarscov2_may_be_at/
#covid19 test: ICMR intensifies random testing to check for covid-19 - The Economic Times
https://m.economictimes.com/news/politics-and-nation/icmr-intensifies-random-testing-to-check-for-covid-19/articleshow/74643047.cms
Each of the 51 Indian Council of Medical Research (ICMR) laboratories is to test 10 such samples every week. The exercise began on March 15. Before this, the ICMR had picked up 20 samples and tested them at 13 labs to check for community transmission between February 15 and 29.
Shri Kodanda Ramachadramuthry Temple, Andhra Pradesh, India
https://www.reddit.com/r/IndiaSpeaks/comments/fjhylt/shri_kodanda_ramachadramuthry_temple_andhra/
శ్రీ కోడంద రామచద్రముత్రీ ఆలయం
#ఆంధ్రప్రదేశ్ #AndhraPradesh #India #కోదండ #కోదండ_రామాలయం #IndianHeritage #IncredibleIndia
Computer Science Students Build Coronavirus Tracking Website | UVA Today
https://news.virginia.edu/content/computer-science-students-build-coronavirus-tracking-website
Physics Professor Lou Bloomfield Explains the Crucial Math Behind Social Distancing | UVA Today
https://news.virginia.edu/content/physics-professor-lou-bloomfield-explains-crucial-math-behind-social-distancing
Raag Gorakh Kalyan | Soumik Datta & Sukhvinder Singh ‘Pinky’ | #Sarod & #Tabla | Music of India
https://www.youtube.com/watch?v=Mshi-7hfKJM
Recorded at #DarbarFestival on 25 Oct 2018, at London’s Barbican Centre:
-Soumik Datta (sarod)
-Sukhvinder Singh ‘Pinky’ (tabla)
#IndianMusic #Raaga #Rāga #राग #सरोद #तबला
The Double Statue of Mephistopheles & Margaretta, Salar Jung Museum, Hyderabad.[768×1024]
🇻🇳 The stone altar of Đồng Dương, #ChampaKingdom, 9th to 10th century, declared as a National treasure of #Vietnam in 2019
https://www.reddit.com/r/ArtefactPorn/comments/fidkvy/the_stone_altar_of_đồng_dương_champa_kingdom_9th/
This caterpillar could potentially help solve one of the world's most pressing environmental problems: plastic waste. It can chomp through plastic — even polyethylene, a common and non-biodegradable plastic currently clogging up landfills and seas. https://t.co/5rk69yR2fX
We asked astronomers: are we alone in the Universe? The answer was surprisingly consistent
http://theconversation.com/we-asked-astronomers-are-we-alone-in-the-universe-the-answer-was-surprisingly-consistent-132088
Avocado a day might give obese adults a brain boost: Study - Lifestyle News
https://www.indiatoday.in/lifestyle/health/story/avocado-a-day-might-give-obese-adults-a-brain-boost-study-1654530-2020-03-11
#ChatrapatiShivaji Maharaj's murti consecrated by himself at the Gopuram of Mallikarjunam Temple in Sri Sailam at the time of his Dakshin Digvijaya in 1677. The Gopuram erected by him was named after him and is still called Shivaji Gopuram
https://www.reddit.com/r/IndiaSpeaks/comments/fij8zt/chatrapati_shivaji_maharajs_murti_consecrated_by/
Statues of Agastya Muni and Nandi were recently discovered while digging in #Yogyakarta, #Indonesia 🇮🇩
https://www.reddit.com/r/IndiaSpeaks/comments/fiea1w/statues_of_agastya_muni_and_nandi_were_recently/
🔸 The parasympathetic and the sympathetic systems are commonly known as 'fight or flight' and 'rest or digest' — and that's true, if we were always at full sympathetic tone or at full parasympathetic tone.
That's not the case. Usually, we're somewhere in the middle.
🔸 We can go sympathetic or parasympathetic according to the needs of the moment, but as we go from being born to old age, we are moving in a steady direction towards more sympathetically dominated.
🔸 Young kids are very parasympathetically dominated. Now, once you get into older age, the sympathetic domination is going to drive up heart rate and it's going to drive up blood pressure — that sounds like hypertension.
🔸 Nothing's changed in old people from childhood, except that now they're sufficiently sympathetically dominated that they've encountered this hypertension.
Joined Nov 2019
