Physiology and Pharmacology Flashcards
What is an exception to the antagonistic formatting of sympathetic and parasympathetic pathways?
The cooperation in achieving males sexual function.
The process of achieving an erection is achieved through the parasympathetic pathway whilst the process of ejaculation is achieved through the sympathetic pathway.
Name 2 structures innervated by only the Synpathetic pathway and how they function under these conditions.
Sweat glands and Blood vessel smooth muscle. This functions due to the up and down regulation of SS control. i.e an increased signal rate causes vasoconstriction whilst a decrease in signal rate causes vasodilation.
What does adrenaline act as and what changes does it bring about?
Acts as a non-selective agonist.
Adrenaline activates both alpha and beta receptors.
Causes blood pressure to increase
Dilares bronchi
What is a medical use for adrenaline?
Used in Epi-Pens to treat anaphylactic shock.
What is are nasal decongestants comprised of?
Alpha 1 selective agonists.
What is salbutamol comprised of?
Beta 2 selective agonists. Targets the bronchial smooth muscle causing them to dilate.
Give an example of a clinical use for Beta 1 selective antagonists.
Proparanolol and atenolol. Beta blockers are used to lower blood pressure and heart rate.
What do muscarinic receptors in the heart do once stimulated?
Decrease heart rate.
What are the effects of ingesting muscarine?
Decreased blood pressure
Increased saliva, tear flow and sweating
Name a use for pilocarpine?
Eye drops, used to treat glaucoma. This reduces the pressure in the eye by increasing the drainage of aqueous humour from inside the eye into the blood stream.
How does high eye pressure result due to glaucoma?
Glaucoma occurs when the trabecular meshwork of the eye becomes partially blocked. This blockage prevents the aqueous humour from draining properly, causing an increase in intraocular pressure which can damage the optic nerve.
What is atropine?
A cholinergic antagonist. It blocks muscarinic receptors.
Name 4 Non-Adrenergic, Non-Cholinergic neurotransmitters (NANC)
Substance P
Nitric oxide
ATP
VIP
What is the ANS and what are its main divisions?
Efferent division of the visceral NS.
Sympathetic and Parasympathetic.
Name 3 differences between the sympathetic and parasympathetic NS?
Pre-ganglionic fivre length, anatomical location, post ganglionic transmitter
What is focal calicification?
Calcium deposition in the arterial walls causing thickenting/toughening.
What is atherosclerosis?
Lipid and monocyte decomposition in the tunica media. Results as a result of cholesterol and LDL build up, alongside a depletion in ApoE.
Where is angeotensinogen produced?
Liver
Where is renin produced?
Kidney as a result of a drop in blood pressure.
What does renin do?
Catalyses the formation of angiotensin 1 from angiotensinogen.
Where is angiotensin converting enzyme produced?
Lungs
What does angiotensin converting enzyme do?
Catalyses the formation of angiotensin 2 from angiotensin 1.
What does angiotnsin 2 do?
Acts as a powerful vasoconstrictor. Allows an increase in Bloop pressure.
What two factors effect systolic pressure?
Ejection Velocity and Stroke volume
What two factors effect diastolic pressure?
Total peripheral resistance and Blood flow from arterial to venous sides.
Name a sympathetic agonist at alpha 1 receptors what increase TPR by vasoconstricting.
Phenylephrine
Name a sympathetic agonist at beta 1 receptors that increases CO by increasing rate and stroke volume.
Dobutamine.
How do digitalis improve muscle contractility?
They inhibit the Na/K ATPase so Na builds up. Built up Na is exchanged for Ca. Ca improves the contractility of the muscle.
Name a sympathetic antagonist at alpha 1 receptors what decrease TPR by vasodilating?
Prazosin
Name a sympathetic antagonist to beta 1 receptors that decreases CO by decreasing rate or stroke volume.
Atenolol
Name a drug that blocks Ca channels
Verapamil
What does TPR stand for?
Total peripheral resistance.
What is hypokalemia?
A deficiency of potassium in the blood.
Name 2 main causes of hypokalemia?
Diuretics and hyperaldosteronism,
Name two syndromes involved in hypokalemia.
Barrters syndrome
Gitelman’s syndrome.
Where in the nephron does most NaCl and water uptake occur?
Proximal convoluted tubule and Descending limb
Name 3 drugs that target ion channels
Lignocaine Apamin and Dihydrophyridines e.g nifedipine.
Name 3 drugs that target enzymes
Acetylsalicyclic acid
Pargyline
Clorgyine
Captopril
Name 2 drugs that target enzymes
Fluxoetine
Digoxin
Name an agoinst for the GABAaR receptor
GABA
Name an antagonist for the GABAaR receptor
Picrotoxin
Describe the structure of a nicotinic receptor
Hetromeric assembly of 5 subunits (pentameric structure)
How many molecules of Ach or Nicotine must bind to a nicotinic receptor to activate it? Where do they bind?
- They bind at interfaces between alpha subunits.
Are receptors for hormones inside or outside the cells?
Inside
Name 7 factors released from the hypothalamus that pass to the pituitary gland.
Thyrotropin releasing factor growth hormone releasing factor growth hormone inhibiting factor corticotrophin releasing hormone GnRH Oxytocin ADH
Where is insulin secreted?
Secreted by Beta Cells in the Islets of Langerhans in the pancreas.
Give 2 stimuli for the release of insulin
Increased blood cluicse concentration
increased blood arginine/leucine levels.
What is metformin and what is its half life?
An oral hypoglycaemic agent of the biguanide group. Has a half life of about 3 hours.
What is diabetes mellitus?
Type 1 and type 2 diabetes
What is diabetes insipidus?
Occurs as the posterior pituitary gland fails to produce adequate levels of ADH resulting in polydipsia (excessive drinking) and polyiria (excessive urination)
Where does fertilisation occur?
The Ampulla of the female reproductive tract
What gene induces testes formation?
Sry gene
What hormones do the testes produce?
Anti-Mullerian hormone (AMH) Also known as Mullerian inhibiting substance (MIS)
Testosterone
What happens if there’s a deficiency in 5 alpha reductase?
This enzyme usually converts testosterone into a more active form 5 dihydroxytestosterone (5DHT). If the enzyme isn’t present then the male genitalia doesn’t differentiate properly.
What degenerates in males?
Paramesonephric duct (mullerian)
What degenerates in females?
Mesonephric duct (wolffian)
What are sertoli cells?
Non-proliferative, tall simple columnar epithelial cells that extend from the basal lamina to the lumen.
what is atresia?
A natrual process of cell death that destroys follicles at all stages of development.
What is polycystic ovarian disease?
When many small follicles develop instead of one dominant one.
What happens to the corpus luteum if fetilisation doesn’t occur?
The corpus luteum degenerates into the corpus albicans.
What do the conducting zones of the respiratory system do?
These provide the pathways to get air to and from the respiratory zone where gas exchange takes place.
How many layers in thick skin?
5
How many layers in think skin?
4
What layer only exists in thick skin?
Stratum lucidium
What are the 5 layers of the skin?
Stratum basale Stratum Spinosum Stratum granulosum Stratum lucidum (only in thick) Stratum corneum
