uterine motility Flashcards
what is found in the endometrium
glands, blood vessels, lymphatics, epithelial cells
what type of gap junction is responsible for uterine contractions
connexin 43
what are the functions of uterine smooth muscle gap junctions
hormonally inducible
fundal dominance during labour due to anatomical arrangement
what are alpha adrenoreceptors in the uterus responsible for
contraction
what are beta adrenoreceptors in the uterus responsible for
relaxation
what hormones stimulate uterine contractions
ADH and oxytocin
both 9 aa proteins
what factor influences oxytocin
receptor numbers and effect on uterine contractions are influenced by sex hormone levels
what hormones are produced by the posterior pituitary gland
oxytocin and ADH
what hormones are produced by the anterior pituitary gland
Growth Hormone (GH), Prolactin (PRL), Follicle-Stimulating Hormone (FSH), Luteinizing Hormone (LH), Adrenocorticotropic Hormone (ACTH), and Thyroid-Stimulating Hormone TSH).
what stimulates oxytocin at the end of pregnancy
falling placental progesterone with sustained oestrogen
stimulates prostaglandin and oxytocin receptors
describe uterine contractions during parturition
increasing regular, co-ordinated contractions that travel from the fundus to the cervix
uterus completely relaxes in between
what are uterine stimulants used for
oxytocics
abortion
induce and accelerate labour
contract the uterus after delivery to control haemorrhage
what are uterine relaxants used for
dysmenorrhoea and menstrual cramps
prevent preterm labour
facilitate obstetric manoeuvers
counteract uterine hyperstimulation
what is IV/ IM oxytocin, ergometrine and E and F prostaglandins
oxytocics
what is ergometrine used for
obstetric haemorrhage by causing sustained uterine contractions (postpartum haemorrhage, PPH)
however largely obsolete now
(other forms for migraine)
what is F series prostaglandin
vasoconstrictor
‘cervical ripening’ and induce oxytocin receptors
what is E series prostaglandin
vasodilator
‘cervical ripening’ and induce oxytocin receptors
what is dinoprostone, carboprost, gemeprost and misoprostol
prostaglandin analogues
describe a medical abortion using prostaglandins
myometrium sensitised by mifepristone which is a progesterone receptor antagonist then misoprostol induces labour
also used to control PPH
what is a tocolytic
uterine relaxant
what is riodrine, terbutaline and salbutamol
b agonists
increases cAMP levels in smooth muscle
uterine relaxant
what are the adverse effects of tocolytics
tachycardia, hypertension and hyperglycaemia
what is nifedipine
the current drug of choice for uterine relaxation
calcium channel blocker
what are NSAIDS used for
reduce PG synthesis so reduce uterine contractions
eg indomethacin
