Physiology of the Autonomic Nervous System

Adrenergic Receptors

Integral proteins activated by norepinephrine and epinephrine.

B₁ Receptors

Adrenergic receptors influencing heart rate and contractility.

B₂ Receptors

Adrenergic receptors causing smooth muscle relaxation.

B₃ Receptors

Adrenergic receptors involved in lipolysis and thermogenesis.

Vasoconstriction

Narrowing of blood vessels, increasing blood pressure.

Vasodilation

Widening of blood vessels, decreasing blood pressure.

Excitation-Contraction Coupling

Process linking muscle excitation to contraction.

Renin Secretion

Hormonal release affecting blood pressure regulation.

Antidiuretic Hormone (ADH)

Hormone regulating water retention in kidneys.

Glycogenolysis

Breakdown of glycogen into glucose for energy.

Thermogenesis

Heat production through metabolic processes.

Agonist

Substance activating a receptor, mimicking natural effects.

Antagonist

Substance blocking a receptor, inhibiting natural effects.

Phenylephrine

Adrenergic agonist used to relieve nasal congestion.

Atropine

Muscarinic antagonist used to dilate pupils.

Propranolol

Nonselective beta blocker reducing heart rate and blood pressure.

Metoprolol

Selective beta blocker targeting specific beta receptors.

Cardiac Muscle Fibers

Muscle cells responsible for heart contractions.

Juxtaglomerular Cells

Kidney cells secreting renin for blood pressure control.

Pancreatic Islets

Clusters of cells in pancreas secreting hormones.

Brown Adipose Tissue

Fat tissue specialized for heat production.

Smooth Muscle Fibers

Involuntary muscle fibers controlling organ movements.

Autonomic Tone

Balance of sympathetic and parasympathetic activity.

Sympathetic Division

Dominates during stress, enhancing physical activity.

Parasympathetic Division

Promotes energy storage and relaxation functions.

Hypothalamus

Regulates autonomic tone between divisions.

Adrenergic Receptors

Bind norepinephrine, affecting sympathetic responses.

Cholinergic Receptors

Bind acetylcholine, affecting parasympathetic responses.

Fight-or-Flight Response

Physiological changes during stress or danger.

Pupil Dilation

Increases light entry during sympathetic activation.

Heart Rate Increase

Elevated heart rate during sympathetic stimulation.

Airway Dilation

Facilitates airflow during sympathetic activation.

Blood Vessel Constriction

Reduces blood flow to non-essential organs.

Glycogenolysis

Breakdown of glycogen to glucose in liver.

Lipolysis

Breakdown of triglycerides to fatty acids.

Increased Blood Glucose

Elevated glucose levels during sympathetic activation.

Digestive Activity Inhibition

Slowed digestion during stress responses.

Sympathetic Postganglionic Axons

Diverge extensively, activating multiple tissues.

Acetylcholinesterase

Enzyme that inactivates acetylcholine quickly.

Norepinephrine

Lingers longer than acetylcholine in synapses.

Epinephrine

Hormone that intensifies sympathetic responses.

Alpha Receptors

Type of adrenergic receptor responding to norepinephrine.

Beta Receptors

Type of adrenergic receptor responding to epinephrine.

Suprarenal Medullae

Adrenal glands releasing hormones during stress.

Parasympathetic Division

Supports rest-and-digest activities for energy conservation.

Sympathetic Division

Dominates during stress, supporting fight-or-flight responses.

SLUDD

Acronym for salivation, lacrimation, urination, digestion, defecation.

Rest-and-Digest

Body functions that restore energy during rest.

Fight-or-Flight Response

Physiological changes preparing body for emergency action.

Decreased Heart Rate

Slows heart function during parasympathetic activation.

Bronchoconstriction

Decreased airway diameter in parasympathetic responses.

Pupil Constriction

Decreased pupil diameter during parasympathetic activation.

Glycogenolysis

Breakdown of glycogen to glucose in the liver.

Lipolysis

Breakdown of triglycerides to fatty acids in adipose tissue.

Increased Blood Pressure

Elevated pressure during sympathetic activation.

Airway Dilation

Increased airway diameter for better airflow in stress.

Blood Vessel Constriction

Reduces blood flow to non-essential organs during stress.

Digestive Activity Reduction

Slowed digestion during sympathetic responses.

Energy Storage Inhibition

Reduced functions supporting energy storage during stress.

Emotional Triggers

Fear and rage stimulate sympathetic activation.

Autonomic Tone

Balance between sympathetic and parasympathetic activity.

E Situations

Exercise, emergency, excitement, embarrassment trigger sympathetic responses.

Digestive Gland Stimulation

Parasympathetic impulses enhance digestive gland activity.

Smooth Muscle Activation

Parasympathetic responses stimulate digestive smooth muscle.

Energy Restoration

Parasympathetic responses focus on restoring body energy.

Sympathetic stimulation

Long-lasting, widespread effects on body functions.

Parasympathetic stimulation

Rest-and-digest activities conserving energy.

Divergence of axons

Sympathetic axons activate multiple tissues simultaneously.

Norepinephrine

Neurotransmitter that lingers longer than acetylcholine.

Epinephrine

Hormone secreted by suprarenal medullae, prolongs responses.

Alpha receptors

Receptors affected by norepinephrine and epinephrine.

Beta receptors

Receptors that respond to epinephrine effects.

SLUDD

Acronym for parasympathetic responses: Salivation, Lacrimation, Urination, Digestion, Defecation.

Decreased heart rate

Parasympathetic response reducing cardiac activity.

Bronchoconstriction

Parasympathetic response narrowing airway diameter.

Pupil constriction

Parasympathetic response decreasing pupil diameter.

Fight-or-flight response

Sympathetic activation preparing body for action.

Energy conservation system

Parasympathetic division restores energy during rest.

Preganglionic neurons

Neurons originating in CNS, synapse with postganglionic neurons.

Postganglionic neurons

Neurons that innervate visceral effectors.

Thoracolumbar outflow

Sympathetic preganglionic neurons from T1-L2.

Craniosacral outflow

Parasympathetic preganglionic neurons from cranial and sacral regions.

Preganglionic axons

Axons that synapse with postganglionic neurons.

Visceral effectors

Tissues innervated by autonomic nervous system.

Sympathetic ganglia

Ganglia located near spinal cord.

Parasympathetic ganglia

Ganglia located near or within target organs.