Please enable JavaScript.

Coggle requires JavaScript to display documents.

Physiology Pt. 1 - Coggle Diagram

- - - - Sensensory discrimitaive component
        
        SIte, onset, intensity, and character
        
        Nocioceptors
      - Emotional Component
      - Autonomic component
      - Motor component
        
        Evaulated and expressed (psychomotor)
  - - - C Fibers = dull, aching, burning pain (small, unmyelinated)
      - Aδ fibers = sharp, pricking (thin, myelinated)
    - - Activators (Potassium, Serotonin, Bradykinin, HIstamine)
      - Sensitizers (Prostaglandins, Leukotienes)
  - - - Damaged tissue, inflammation release chemical mediators that activate/sensitise nocioceptors
    - - lesions in the CNS or dysfunction in the PNS can activate central pain pathways and rive LT neuropalstic changes
  - - - Hydrodynamic theory - movement of dentinal fluid exctes mechanoreceptive receptors in the subodonto plexus
      - Found in the odontoblasts and primary afferebt nerves in the pulp
  - - - Fast-Sharp (A delta) synapse in the doral horn, and cross over and ascend in the neo tract to thalamus to the primary somatosensory cortex
    - - Slow chronic (C fibers) - synapse with different inter neurons and cross over to ascend in the paleo and into different structures within the midbrain and thalamus
    - - Afferent C fibers synapse in the trigeminal nuclei, and ascend or cross over to go to the thamalmus and innervate the hypothalamus (SNS), limbic (emotion) somatosensory(location)
      - Afferent A delta fibers analagous to the neospinothalamic, fast and shartp, helps to localise the pain within the somatosensory cortex
  - - - Usually pressure on a nerve, can cuase the peripheral area of stimulation to be felt as pain, due to the afferent signals along that nerve being activated
      - Tx: Aniconsulstants or surgery
  - - - Gate-control mechanism = large diameter A alpha and beta fibers activate interneruons to inhibit transmission of pain
      - Rubbing skin after a painful blow
    - - Stimulation of the grain at several sites aids in analgesia by releasing there on N.T and descinding them to inhibit the afferent signals
- - - - Temperature
      - Fluid Volume Balance
    - - Arterial BP
      - Aterial PO2
      - Blood Glucose
      - Plasma free Ca++
    - - Mucle tone
      - Cardiac Output/Venous return
    - - Ion Concerntration
      - Cell pH/HCO3/H+
  - - - Thermoregulation of the skin
      - Rapid movements (ie typing)
      - CNS functions (ie swallowing)
    - - Feedback gain - is the amount of correction/amount of abnormality still required (ie number..)
  - - - produce the peptide hormones vasopressin (ADH) or oxytocin
        
        Vasopressin is critical for body water homeostasis and arterial BP regulation
    - - Release of tropic hormones (e.g., TSH, ACTH, GH, LH, FSH, Prl)
      - hypophysio-pituitary portal circulation into the blood
  - - - secreted by the parathyroid gland chief cells in response to low plasma Ca++
        
        Increase adsorption of Ca++ in intestine
        
        Increase osteoclast activity for bone resorption and Ca++ efflux
        
        Increase Ca++ resabsorption in kidneys
    - - secreted by the parafollicular cells of the thyroid gland when plasma Ca++ is too high
        
        inhibits bone resorption (inhibits osteoclast differentiation)
    - - b) Vit D3 is metabolically activated in liver (by PTH) then kidney to 1,25(OH)2D3 (calcitriol)
        
        c) intestinal epithelium then bind calcium and adsorb it to increase plasam ion concerntrations
  - - - Changes in skin temperature + Core temperature are intergrated bythe thermoregulation centre in the hypothlamus
        
        efferent signals are sent to the body
        
        Hormonal
        
        ↑ TRH
        
        ↑ TSH
        
        thyroid gland releases T3/4
        
        1 more item...
        
        Neural
        
        Feedfoward mechanism
        
        Behavioural: adjustments to thermostat,air con, put clothes on/off
        
        Shiver (Muscle)
        
        Piloerection (Sympathetic)
        
        Sweat/Evaporation (Sympathetics via sweat glands)
        
        Vasodilation/constriction (smooth muscle)
- - - - Eg. Procaine, benzocaine
      - Degraded in plasma
    - - E.g lignocaine, prilocaine, articaine, mepivicaine
      - Degraded in liver
    - - Effectiveness is depended by the pH
      - LA is affected by inflammaed tissues as there is a lower pH, this reduces the no. un-ionized forms of LA
- - - - Cyclooxygenase (COX) inhbitors an dprevent production of prostaglandin tehrfore reducing nociceptor senseitization
      - Cox's
        
        Cox 1 = Maintain platelet aggregation and gut mucosa
        
        Cox 2 = Induced with tissue injruy (pain, vasodilatation, fever)
      - Aspirin (irrversible COX1- and COX2)
      - Ibuprfen and Naproxen (non-selective Cox inhibitors)
    - - Opioids bind mu receptors and inhibit substance P release from nociceptors at primary CNS afferbet synapses and also reduce their excitablity for new signals
      - Ex. Codeine, DHC, Sevredol
      - Often used in combination with otehr analgesics for a synergistic reponse
- - - - Proprioceptors in skeletal muscle
    - - Pain & temperature
    - - Temp, pain & itch
    - - Chemically gated i.e taste receptors
      - Voltage-gated i.e. touch receptor (where membrane deforms undere pressure)
      - Receptive Field - area over which stimulation can occur
        
        Two-point discrimination is very good in the tongue, lips, and oral mucosa, as there is a large no. sensory units, small receptive fields and overlaps which allow for precision
      - Coding
        
        Modality
        
        What is it? reponse to specific stypes of stimuli
        
        Intensity
        
        SIze of the stimulus, frequency of coding
        
        Recuitment and adapatation can occur for larger or constant stimuli
        
        Location
        
        Where is it
        
        Receptive fields, discrimination
        
        Somatotropic organization in the sensory pathway
      - Adaptation - reduction in firing frequency with constant situmulus
    - - Skin mechanorecptors, PDLs
    - - Skin of the face and TMJ
        
        (Very rapid adapting) Pacinian corpusles
        
        (Slow adapting) Ruffini's Corpucle, Merkel's receptors, tactile
        
        (Rapid adapting) Meissner's corpuscle, hair follicle receptor
      - PDLs
        
        Ruffini-like Corpuscles (slow adapting) = accurately describes forces applied to teeth
        
        Which teeth are in contact, direction, amount of force
        
        Aids in the reflex of masticatory muscles
      - Muscle Spindles
        
        Primary - middle part of the intrafusla fibers (Type 1, fast sensory afferents)
        
        Secondary - peripheral - Type II, slower afferent fibers
        
        Gamma Motor Nuerons - innervate the muscle spindles (helps the relax/contract of the spindle)
      - Joints Receptors
        
        Golgi Tendon Organ
        
        Found inbetween the muscle and tendon
        
        Responds to mechanical deformation = low forces (stretch and force)
        
        Not found in the jaw muscles (likely PDL have repalced them)
        
        For limits of motion (ie flexion or extension limits)
        
        Include: Ruffini, Pascini, Golgi, Free Nerve endings
    - - Dorsal Column-medial lamiscal
        
        Afferent signals go to interneurons (ganglia) into the dorsal root and ascend ipislateral
        
        Fine touch, vibration, proprioception, pressure
        
        Synapse in the dorsal column nuclei, cross over and up to the thalamus and organised in the sensory cortex
      - Anterolateral (spinothalamic)
        
        Afferent signals go to an interneuron, into the dorsal root ganglia and synapse to then cross to the other side and ascend controlateral
        
        They ascend straight to the thalamus to then be organised by the sensory cortex
        
        Thermal & pain
  - - - Reinforces apetite
      - Edibility of food
        
        Taste aversions - bad experiences create aversions
        
        Protective reflexes
      - GIT reflexes
        
        Salivation
        
        Digestive enzymes
      - Homeostasis
        
        Salt and potassium balance
    - - Papillae
        
        Circumvallate
        
        Terminal posterior boarder (~10)
        
        Vollate Papillae
        
        Lateral aspect of anterior tongue
        
        Fungiform papillae
        
        Lateral sepct of the tongue, numerous (~250)
        
        Taste Buds
        
        Modified epithelial cells, with Special Visceral Afferent
        
        Degenerate if denervated
      - Five primary tastes
        
        Sweet, Salt, Sour, Bitter and Umami
      - Innervation
        
        Anterior 2/3 - CNVII (Chorda Tympani)
        
        Posterior 1/3 - CNIX (Glossopharyng)
        
        Epiglottis/Tonsilar Pillars - CNX (Vagus)
    - - (Direct Mediated) = Tastant causes membrane changes and causes Vg Ca++ channels to open
      - (Secondary Mediated) Tastant binds receptor causing g-coupled protein receptors to phosphorylate a membrane-bound protein to have a similar depolarising effect
    - - Central integration of taste afferents with other sensations
        
        Olfactory (CNI) - Smell
        
        Touch (CNV) - Mouth feel
        
        Pain (CNV3) - caspacin, mints ect
        
        Temp (CNV3) - ice cream, hot ect