autonomic nervous system

• What is the Autonomic Nervous System (ANS)?

  It is a part of the peripheral nervous system.
• What physiological processes does the ANS regulate?

  It regulates involuntary physiological processes such as heart rate, blood pressure, and respiration.
• Why is the ANS crucial for the body?

  It is crucial to short-term body homeostasis.
• Into what two systems is the ANS anatomically divided?

  Sympathetic Nervous System (SNS) and Parasympathetic Nervous System (PNS).
• What type of signaling does the ANS allow at targets?

  It allows push-pull signaling at targets such as muscle contractions and relaxation.
• When is the Sympathetic Nervous System (SNS) activated?

  It is activated during stress.
• What is the main transmitter of the SNS?

  Noradrenaline.
• When is the Parasympathetic Nervous System (PNS) activated?

  It is activated during rest.
• What is the main transmitter of the PNS?

  Acetylcholine.
• What happens to sympathetic activity during stress?

  Sympathetic activity increases, leading to a fight or flight response.
• What is the catabolic effect of the SNS?

  It involves breaking down stores, such as glucose breakdown.
• What is the anabolic effect of the PNS?

  It involves building up stores, such as glucose storage.
• How do the SNS and PNS work together?

  Both systems work at the same time, constantly active and ready to respond to situations.
• What is the role of the SNS in preparing for action?

  SNS prepares for action by increasing heart rate and secretion of endocrine hormones like adrenaline.
• What physiological changes occur during the fight or flight response?

  Increased heart rate, increased blood pressure, and dilation of skeletal muscle blood vessels.
• How does a giraffe maintain brain oxygenation when standing up?

  A sudden reflex response increases blood flow to the brain to prevent fainting.
• What happens to carotid artery blood pressure when standing up?

  Carotid artery blood pressure falls due to gravity.
• What is the autonomic baroreceptor reflex?

  It is a reflex that increases heart rate and systemic blood pressure when standing up.
• What is the purpose of autonomic testing in clinical trials?

  To test the effect of a new drug on the ANS.
• Which organ is NOT part of the ANS control?

  Skeletal muscles.
• What are the two main transmitters of the PNS and SNS?

  Acetylcholine and Noradrenaline.
• What is the role of acetylcholinesterase (AChE)?

  AChE is responsible for rapid hydrolysis of ACh at synapses.
• What are the effects of anticholinesterase agents?

  They can cause bradycardia, hypotension, and excessive secretions.
• What are organophosphates used for?

  They are used as insecticides and nerve gases.
• What is the structure of muscarinic receptors?

  They are G-protein coupled receptors with 7 transmembrane segments.
• What are the main effects of muscarinic agonists?

  Bradycardia, vasodilation, and contraction of visceral smooth muscle.
• What is the clinical use of Pilocarpine?

  It is used in glaucoma to decrease intraocular pressure.
• What are the effects of muscarinic antagonists?

  Inhibition of secretions, tachycardia, and relaxation of smooth muscle.
• What is the role of β-adrenoceptor antagonists?

  They antagonize sympathetic-mediated increases in cardiac output.
• What is the main use of adrenaline in emergencies?

  It can be used to chemically stimulate the heart during cardiac arrest.
• What is the role of β2 agonists in respiratory conditions?

  They are used to treat asthma by relaxing bronchial smooth muscle.
• What are the main functions of the SNS and PNS?

  • SNS: Fight or Flight, mass discharge, adrenaline release
  • PNS: Rest, refueling, reflexes, tonic activity
• How do nicotinic receptors function at autonomic ganglia?

  Nicotinic receptors are ion channels that mediate fast transmission.
• What is the significance of the structure of muscarinic receptors?

  They interact with G-proteins to activate various intracellular pathways.
• What is the role of acetylcholine in the ANS?

  Acetylcholine acts as a neurotransmitter in both the PNS and SNS.
• What are the effects of adrenergic receptors in the SNS?

  They mediate responses such as increased heart rate and blood pressure.
• What is the role of the adrenal gland in the SNS?

  The adrenal gland releases adrenaline during stress responses.
• What is the mechanism of action of tricyclic antidepressants?

  They inhibit the reuptake of noradrenaline at sympathetic varicosities.
• What is the effect of β1 selective blockers?

  They reduce cardiac output and renin release in the kidney.
• What is the role of the vagus nerve in the ANS?

  The vagus nerve is involved in parasympathetic control of heart rate and digestion.