Block 11 Flashcards
What is Folic acid?
What enzyme converts folic acid to tetrahydrofolic acid methyltetrahydrofolate?
What are tetrahydrofolic acid and methylhydrofolate needed for? (5)
What is folic acid used for? (2)
DNA precursor.
Dihydrofolate reductase.
Maintain normal erythropoiesis, synthesise purine and thymidylate nuclei acids, interconvert amino acids, methylated tRNA, generate and use formate.
Prevention of folate deficiencies and megaloblastic anaemia.
Name 3 drugs which are synthetic versions of progesterone.
What are these drugs used for?
Which one can be used for emergency contraception?
What is the mechanism of action of these drugs?
Desogestrel, Etonogestrel, Levonogestrel.
The oral contraceptive pill (+/- oestrogen)
High dose levonogestrel.
Bind to progesterone and oestrogen receptors, slow the frequency of release of GnRH from hypothalamus, blunt pre-ovulatory LH surge, maintain high levels of progesterone.
What is paracetamol?
What does paracetamol lack?
What might the mechanism of action of paracetamol be?
What are the antipyretic effects of paracetamol due to?
Analgesic and antipyretic compound.
Anti platelet, anti inflammatory and gastric ulcerative effects.
Indirect inhibition of COX.
Direct inhibition of COX 3.
Effects on the hypothalamus = peripheral vasodilation and sweating.
What is Oxytocin?
What does Oxytocin stimulate?
When is Oxytocin used?
What is the mechanism of action of oxytocin?
What is Oxytocin after labour associated with?
A hormone used to induce labour (A GPC agonist)
Used to stimulate contraction of the uterine smooth muscle.
Used in delivery and immediately post partum.
Activates receptors on the uterus > increases intracellular calcium ion release > activates myosin light chain kinase > causes muscle contraction.
Lactation.
What is Oxytocin thought to do in men? (2)
Be involved in the movement of sperm.
Be involved in the production of testosterone.
What is dinoprostone?
In what situation does dinoprostone have important effects in?
What is the supposed mechanism of action?
What is dinoprostone used for as a prescription drug?
A prostaglandin E2 receptor agonist.
Important effects in labour.
Via direct myometrial stimulation.
A vagina, suppository for cervical ripening and inducing labour.
Name 2 oestrogen hormone receptor agonists.
What is the mechanism of action?
What is the role of these during menstruation?
Where is oestradiol produced?
Oestradiol and ethinyloestradiol.
Interact with oestrogen receptors (ER alpha and beta) > ER enters nucleus and regulates gene transcription > increases hepatic synthesis of hormones that suppress FSH release from APG.
Increased oestradiol levels cause maturation and release of egg, thickening of uterus lining. These actions allow a fertilised egg to implant.
Primarily in the ovaries, meaning that levels reduce as women age and decrease significantly during menopause.
