migraine pathology: Migraines are thought to be caused by the release of peptide neurotransmitters (primarily the calcitonin gene-related peptide, viz. CGRP) from the trigeminal nerve distribution into the intracranial arteries. These neurotransmitters are known to be powerful vasodilators resulting in cranial vasodilation. This may further lead to extravasation of blood plasma and plasma proteins resulting in perivascular oedema. Perivascular oedema can cause mechanical stretching, leading to activation of pain nerve endings in the dura which may be the cause of the painful headache associated with migraines.

migraine treatment:

• ergot alkaloids: eg. Ergonovine. Partial agonist at 5-HT and at alpha-adrenoreceptors especially in vessels thereby preventing the vasodilation associated with migraines.
• triptans: eg. sumatriptan. Selective agonists for 5-HT1D and 5-HT1B: this causes vasoconstriction and prevents the vasodilatory effects of the migraine as well as the pain associated with it, they also modulate neurotransmitter release thus reducing the amount of CGRP.
• anti-inflammatory analgesics (NSAIDs): eg. asprin. Effective in pain management of pain associated with migraines.
• beta-blockers: eg. propanolol. Effective in the prophylaxis of migraine.
• anticonvulsants: eg.topiramate, valproic acid. Used in the prophylactic treatment of migraines.
• calcium-channel blockers: eg. verapamil, flunarizine. Effective in the prophylaxis of migraine.

Question 1: Giver your own definition of COPD

It is a combination of lung diseases that prevent airflow resulting in difficulty in breathing. Some of the most common conditions that make up COPD are: Emphysema (condition where the walls of the air sacs of the lungs are damaged), bronchial asthma (condition where a persons airway become swollen and produces extra mucus which makes breathing difficult) and chronic bronchitis (inflammation of lining of bronchial tubules). Damage to the lungs from COPD can not be reversed.

Question 2: Briefly describe the proposed aetiology and pathophysiology of chronic bronchitis and emphysema

• Emphysema:                                                                                                                                                   

The cause of emphysema is generally continuous exposure to irritants that  damage your lungs and their airways.  The damage done to the alveoli eventually leads to reduced elasticity and over-inflation. This therefore causes swelling of the bullae where the CO2 becomes trapped. Due to this reason the lungs are being deprived of continuous flow of oxygen therefore causing deeper breathing. Emphysema is therefore known as a lung condition that causes shortness of breath.

• Chronic bronchitis:

It is a non-specific obstructive airway disease which is characterized by: reduced mucus secretion and mucosal clearance, recurring bacterial respiratory infections, changes in bronchial walls and chronic cough due to sticky mucus. The bronchial lining becomes inflamed and continuous exposure to smoke, excessive dust or chemicals will eventually cause damage to the bronchioles. Chronic bronchitis is due to hypersecretion of mucus by the goblet cells. The epithelial cells lining the airway responds to infectious stimuli by freeing inflammatory mediators.

Question 3: Which types of therapy are included in the treatment of a COPD patient?

• stop smoking.
• Airway obstruction: Bronchodilators.
• Hypoxia: Oxygen inhalation.
• Poor lung capacity: Regular exercise.
• Bacterial infection: antibiotics against influenza.
• surgery: lung transplant.

Question 4: Why is ipratropium more effective in the treatment of chronic bronchitis than in the treatment of bronchial asthma?

Ipratropium is a muscarinic Ach receptor antagonist which prevents the function of parasympathetic nervous system. The function includes: the production of bronchial secretions as well as constriction. If this is prevented it will result in bronchodilation and less secretions. Ipratropium is therefore more effective in the treatment of chronic bronchitis since it is characterized by increased mucus secretion. With bronchial asthma, the increased mucus secretion does not have the same effect.

Question 5: In which way do the skeletal muscle effects of theophylline have advantages in the treatment of COPD 

Theophylline improves ventilation response, decreases hypoxia and dyspnea in COPD patients. It causes the smooth muscle relaxation which further causes bronchodilation. This allows for easier flow of air to the bronchial air passage therefore, significantly improves breathing.

Question 6: What is the role of oxygen therapy in COPD?

Increases the amount of oxygen that flows into your lungs and bloodstream and as a result this improves breathing.