KIN 292 1nd Edition Lecture 18These are the notes from Professor Starnes’ lecture of Clinical Human Physiology. These come from the slideshows provided by the professor and include extra notes and explanations. Highlighted or bolded information are things that I believe to be information that is important to look over multiple times. The notes in red are my personal additions and quotes of Professor Starnes from the class lecture. Outline of Last Lecture I. Chapter 10- 10.1 and 10.2II. Exam 2Outline of Current Lecture I. 11.1 The Autonomic Nervous SystemII. 11.2 The Somatic Nervous SystemCurrent LectureAutonomic and Motor Systems – the efferent branch of PNS. Composed of:- The Autonomic Nervous System – regulates the function of most of your effector organs without your control or knowledge. Also referred to as the involuntary system for lack of volition- The Somatic Nervous System – controls only skeletal muscle function and it is under yourcontrol. Volition: definition the act of willing, choosing, or resolving11.1 The Autonomic Nervous System Outline- Dual innervation in the autonomic nervous system- Two opposing divisions or branches innervate most organs- Anatomy of the autonomic nervous system- Regulation of autonomic function- Autonomic neurotransmitters and receptors- Autonomic neuroeffector junctionsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Autonomic nervous system is under dual innervation from sympathetic and parasympathetic divisions- Neuron originso Sympathetic – Thoracolumbaro Parasympathetic – Craniosacral- Primary function: regulate organs to maintain homeostasis- Parasympathetic: rest- Sympathetic: fight-or-flight response- Two types of neurons from CNS to effector organs:- Preganglionic – CNS to autonomic ganglion- Postganglionic – autonomic ganglion to organ- Autonomic ganglia are busy communication centers:o A preganglionic neuron synapses with many postganglionic neurons- Ganglia also contain intrinsic neurons that modulate information being sent to effectororgans3 neural anatomy patterns in the sympathetic nervous system.1. Sympathetic chain- Ganglia connected by preganglion collaterals. Allows for simultaneous activation of many organs2. Direct to modified postganglion cells (endocrine) in adrenal medulla (Fig. 11.5)3. Travel through sympathetic chain without forming a synapse. Forms synapses in one of 3 collateral ganglia that innervate only selected target organs. Allows for more discrete or specific results compared to #1&2 aboveParasympathetic nervous system pathways- Long preganglionic neurons directly to ganglia near the effector organ. Short postganglionic neurons- Cranial nerves (see Fig. 11.1)o Cranial nerve X = vagus nerve – much of viscerao Cranial nerve III = oculomotor – smooth muscle in pupil and lenso Cranial nerve VII = facial nerve – salivary glandso Cranial nerve IX = glossopharyngeal nerve – smooth muscle in throat and viscera of thorax and abdomenThe Mixed Composition of Autonomic Nerves- Nerveo Definition. A bundle of axons (fibers) in the PNS; connects the CNS with organs inthe periphery- Autonomic nerves haveo Fibers sending action potentials in two directionso Efferent fibers to regulate effector organs ando Afferent fibers from visceral receptors to CNS- Important in maintaining homeostasisRegulation of Autonomic Function- Dual innervation of organs – both sympathetic and parasympathetic nerves- Visceral receptors (within body) send afferent signals to specific locations in the brainwhich process the information and decide how much sympathetic and parasympathetic activity is required to maintain homeostasis in each organ at any particular moment or activity- Increases in parasympathetic activity are coupled with decreases in sympathetic activity and vice versaAutonomic reflex response that controls blood pressure when a person stands up. An example- Regulation: General Process.- Visceral receptors send afferent signals to specific locations in the brain which process the information and decide how much sympathetic and parasympathetic activity is required to maintain homeostasis in each organ at any particular moment or activityRegulation of Autonomic Function- Parasympathetic activityo Quiet, relaxed stateso Active in "rest and digest"o Increases gastrointestinal activitieso Decreases heart rate and blood pressure- Sympathetic activityo Fight-or-flight responseo Prepares for emergency, stress, and exerciseo Increases heart rate and blood pressureo Mobilizes energy storeso Dilates pupilso Decreases gastrointestinal and urinary functionsTonic Activity at Rest- Both branches active- Parasympathetic nervous system dominates- Endurance exercise training enhances the parasympathetic domination at rest and during light exercise intensities resulting in lower resting heart rate and some other changesAutonomic Neurotransmitters and Receptors- Types of cholinergic receptors- Types of adrenergic receptorsNeurotransmitters of the Autonomic Nervous System- Preganglionic neuronso Acetylcholine - Parasympathetic postganglionic neuronso Acetylcholine- Sympathetic postganglionic neuronso Norepinephrine- Hormones of the adrenal medulla (secreted to blood)o 80% epinephrineo 20% norepinephrineTypes of Cholinergic Receptors- Nicotinic cholinergic receptors (ionotropic)o Cause cation channels to open o Channel opening results in depolarization- Muscarinic cholinergic receptors (metabotropic)o G protein coupledo Effect depends on target cellTypes of Adrenergic Receptors- Two main classes: alpha and beta - Each has subclasses- All are coupled to G proteins- Alpha Receptorso Alpha 1 (α1)o Alpha 2 (α2)- Beta Receptorso Beta 1 (β1)o Beta 2 (β2)o Beta 3 (β3)- Specific drugs target specific receptors to treat specific clinical issuesAutonomic Neuroeffector Junctions- Synapses between efferent neuron and effector organ in the autonomic nervous system- Neuroeffector junctiono Between postganglionic neuron and effector organo Neurotransmitter stored in axon swellings Varicosities  Released in response to action potential in postganglionic neuronNeuroeffector junctions –synapses at effector organs in autonomic nervous system.Neurotransmitter release from varicosities.- Release mechanism is very similar to that of a normal axon terminal- Exceptions1. NT released from all vericosities, each one is