Oxytocin and vasopressin
They are very 'guai' hormones... Never go out and club one.. So they travel via their parents' cars (meaning neurons from the hypothalamus as their axon span down to the posterior pituitary)...
They are made from normal papa and mama (DNA to mRNA to hormones) but their post-translation is unique (tt's why they are so obedient; nv go club and all..) Preprohormone become prohormones by cleaving of a signal peptide (that signal chaos? That's why so guai la..) in the ER. Then they got packed into secretory granules in the Golgi apparatus.. The provasopressin is cleaved to give neurophysin II, glycoprotein and vasopressin while prooxytocin is cleaved to give neurophysin I and oxytocin.
The neurophysin of the hormones also very 'guai lan', refused to leave the hormones and therefore bind noncovalently to the hormones.. Luckily for the hormones, the neurophysin got use ar.. Transport the hormones down the posterior pituitary to the terminal bulb...
Secretion of these hormones is via depolarisation, action potential and Ca voltage-gated channel which fuses the secretory granules with the membrane of the neuron.. All these happen because of stimuli (due to contraction of myometrium or myoepithelial or decreased in blood volume or increase in body fluid osmolarity - lets think about all these as tragedy.. Zzz..)
Secretion of these hormones is via depolarisation, action potential and Ca voltage-gated channel which fuses the secretory granules with the membrane of the neuron.. All these happen because of stimuli (due to contraction of myometrium or myoepithelial or decreased in blood volume or increase in body fluid osmolarity - lets think about all these as tragedy.. Zzz..)
So the child (oxytocin and vasopressin) must SAVE them!!
Oxytocin encourages positive feedback loop (you know i know the effects la.. )...
Vasopressin (WHAT DID U DO SIA..).... ......... ....... ......
increase water uptake by kidney thru aquaporin 2 water channel??
Ahhh.... go study la...
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