Pharmacology Flashcards
Sympathetic adrenergic innervation of the airways is the dominant neuronal control of bronchial smooth muscle. True/False?
False
Parasympathetic cholinergic innervation dominates the airways
Stimulation of parasympathetic division causes bronchial smooth muscle _____, mediated by __ acting on __ receptors
Contraction, ACh, M3
Mucus secretion is increased when parasympathetic division is active. True/False?
True
There is no sympathetic innervation of bronchial smooth muscle. True/False?
True
What do postganglionic sympathetic fibres supply with regards to airways?
Submucosal glands
Smooth muscle of blood vessels
Stimulation of sympathetic division causes bronchial smooth muscle _____, mediated by __ released from the ___ ___ acting on __ receptors
Relaxation, adrenaline, adrenal gland, B2
Mucus secretion is increased when sympathetic division is active. True/False?
False
Mucus secretion decreases; mucociliary elevator activity increases
Asthma is irreversible obstruction of small airways. True/False?
False
It is reversible
What are the pathological changes that may occur in chronic asthma?
Increased mass of smooth muscle
Accumulation of interstitial fluid
Increased mucus secretion
Epithelial damage
FEV1 and PEFR increase in asthma sufferers. True/False?
False
They both decrease
What causes hypersensitivity of airways in asthma?
Epithelial damage, exposing sensory nerve endings
What are the 2 components of an asthma attack?
Initial bronchospasm followed by late inflammation
In non-atopic individuals, THo cells mature into TH_ cells
TH1
TH1 suppresses the production of which TH cell?
TH2
In atopic individuals, THo cells mature into TH_ cells
TH2
TH2 suppresses the production of which TH cell?
TH1
Which interleukin helps/allows TH2 cells to activate B cells?
IL-4
Activated B cells can mature into plasma cells which secrete __ in the allergic response
IgE
IgE binds to eosinophils and mast cells via which receptor?
FcE
Which interleukin causes eosinophils to differentiate and activate?
IL-5
Which interleukins cause mast cells to express IgE receptors?
IL-4 and IL-13
When mast cells are activated, which substances do they release?
Histamine
Chemokines
Leukotrienes
Relievers act as anti-inflammatory agents. True/False?
False
They are bronchodilators used for acute attacks
Name the 3 main types of relievers used in asthma
SABAs, LABAs, CysLT antagonists
Name controllers/preventers used in asthma
Glucocorticoids, chromoglicate
What does PKA do in bronchial smooth muscle?
Phosphorylates MLCK and B2 receptors
MLCK’s action is to cause relaxation of bronchial smooth muscle. True/False?
False
Action is to cause contraction; phosphorylation by PKA inhibits this action to cause relaxation
How does PKA cause desensitisation of B2 receptors?
Phosphorylates the receptor, causing reduced G-protein coupling
B2 receptor can be phosphorylated by PKA when no agonist is bound. True/False?
True
How does GRK cause endocytosis of B2 receptors?
Phosphorylates the receptor, allowing B-arrestin to bind and “arrest” the receptor’s signalling function and cause endocytosis
B2 receptor can be phosphorylated by GRK when no agonist is bound. True/False?
False
Agonist must be bound
Give an example of a SABA
Salbutamol
SABAs are usally administered via the _____ route. Why?
Inhalational
Reduces systemic effects
Give an example of a LABA
Salmeterol
LABAs are recommended for acute relief of bronchospasm. True/False
False
They are slow to act
LABAs can be used as a monotherapy. True/False?
False
They would desensitise receptors
CysLT1 receptor activation causes bronchodilation. True/False?
False
Causes bronchoconstriction and inflammation
Give an example of a CysLT antagonist?
Montelukast
Zafirlukast
CysLT antagonists are less potent than salbutamol in acute asthma. True/False?
True
How are CysLT antagonists administered (which route)?
Oral
Give an example of a Xanthine?
Theophylline
Aminophylline
Xanthines have little adverse effects. True/False?
False
Nausea, vomiting, headache are some of the side effects
What are the 2 main classes of corticosteroid released by the adrenal cortex?
Glucocorticoids
Mineralocorticoids
What is the effect of cortisol on inflammatory responses?
Decreases them
What is the effect of cortisol on gluconeogenesis?
Increases it
What is the function of mineralocorticoids?
Regulate salt and water retention by the kidney
Glucocorticoids have good bronchodilator action. True/False?
False
How do glucocorticoids enter cells?
Diffusion - they are lipophilic
Glucocorticoids combine with GRa which causes dissociation of which class of proteins?
HSP (heat shock proteins)
Glucocorticoids stimulate production of proteins which suppress inflammation. True/False?
True
Also decrease production of proteins which stimulate inflammation
Expression of inflammatory genes is associated with the acetylation of histones by which enzyme?
Histone Acetyltransferases (HATs)
What does acetylation do to DNA?
Unwinds it, enabling transcription to occur
What are some cellular effects of glucocorticoids in asthma?
Decrease numbers of eosinophils, mast cells, T cells, macrophages
Increase expression of B2 receptors
Give an example of a glucocorticoid used in asthma and its adverse effects
Inhaled beclomethasone
Hoarse voice + oral thrush
Also oral prednisolone in combination for severe asthma
COPD can be divided into which 2 disease states?
Chronic bronchitis
Emphysema
Describe chronic bronchitis and its symptoms
Inflammation of bronchi + bronchioles
Causes cough + purulent sputum
Describe emphysema and its symptoms
Collapse of alveoli, decreasing SA available for gas exchange
Breathlessness
What is the function of M1 receptors at ganglia?
Facilitate transmission mediated by ACh acting on nicotinic receptors
What is the function of M2 receptors on the post-ganglionic neurone?
Inhibit further release of ACh
What is the function of M3 receptors in smooth muscle?
Mediate contraction + increased mucous secretion in response to ACh stimulation
Give an example of a SAMA
Ipratropium
Give an example of a LAMA
Tiotropium
Ipratropium is a selective blocker of M3 receptors. True/False?
False
Tiotropium is a selective blocker of M3; ipratropium is non-selective
Why is block of M2 receptors undesirable?
M2 receptor normal function is to inhibit ACh release. If this is blocked, more ACh will be released which will ultimately cause more contraction
What is Indacaterol?
An “ultra-LABA” which has rapid onset of action (vs salmeterol)
A combination of LABA + LAMA is not recommended. True/False?
False
This combination is superior to using each drug alone in increasing FEV1
What is the function of a PDE4 antagonist? Give an example of one
Inhibits inflammation caused by PDE4 released by neutrophils
Rofumilast - oral for severe COPD
What is rhinitis and its symptoms?
Inflammation of nasal mucosa
Typically rhinorrhoea, sneezing, itching, nasal congestion
What is non-allergic rhinitis and its causes?
Rhinitis not involving IgE
Infection, drug-induced, hormonal, idiopathic
List drug classes that can be used for rhinitis
Glucocorticoids
H1 and cysLT1 receptor antagonists
Sodium chromoglicate
Mechanism of action of H1 receptor antagonists
Examples
Reduce effects of histamine released from mast cells
Given orally or nasal spray
Loratidine, fexofenadine, cetirizine
Mechanism of action of sodium chromoglicate
Mast cell stabilisation
Nasal spray, usually better for children