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EMAK · Century Club Joined: 26 Nov 2006 Posts: 572

During pregnancy, estrogen cause hypertrophy and hyperplasia of ant. pituitary gland with hyperprolactinaemia but milk production is inhibited by estrogen at the same time....

My Q regarding synthetic estrogen (COC),, are they a cause of hyperprolactinaemia and do they cause pituitary enlargement????

Abik · Posted: Wed Jan 17, 2007 5:22 pm Post subject:

Oestrogens can cause hyperprolactinaemia but I'm not sure about pituitary enlargement. What about HRT?

Nick Raine-Fenning · Posted: Wed Jan 17, 2007 9:00 pm Post subject:

Pretty sure they do both - always think of the effects of pregnancy when asked about the effects of the COCP.

Not so sure about HRT as it provides physiological levels of oestrogen.
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Shinelkimo · Joined: 25 Apr 2007 Posts: 55

Except COCP, what else medications can cause hyperprolactinemia

farha · Century Club Joined: 18 May 2007 Posts: 156

dOPAMINE DEPLETING AGENTS like reserpine , methyldopa and dopamine receptor inhibbiting agents like phenothiazine and meteclorptomide

rpwalavalkar · Teale Fenning Administrator Joined: 20 Jul 2006 Posts: 966

drugs causing hyperprolactinemia ----

Dopamine receptor antagonists
phenothiazines,
butyrophenones,
thioxanthenes,
risperidone,
metoclopramide,
sulpiride,
pimozide

Dopamine-depleting agents
methyldopa,
reserpine

Others
isoniazid,
danazol,
tricyclic antidepressants,
monoamine inhibitors,
verapamil,
estrogens,
antiandrogens,
cyproheptadine,
opiates,
H2-blockers [cimetidine],
cocaine
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Dr Miss. Raj Walavalkar MBBS MRCOG
TealeFenning Administrator
SR O&G Wessex Region

Shinelkimo · Joined: 25 Apr 2007 Posts: 55

1. why Cushing disease is associated with hyperprolactinemia but Cushing syndrome not?

2. is Phenytoin and amitriptyline associated with hyperprolactinemia?

rpwalavalkar · Teale Fenning Administrator Joined: 20 Jul 2006 Posts: 966

answer query 1.

Cushing's syndrome is due to long-term exposure to excessive glucocorticoids. The syndrome is most commonly caused by the therapeutic administration of exogenous glucocorticoids.

Cushing's disease is Cushing's syndrome that is caused by excessive secretion of adrenocorticotropin hormone (ACTH) by a pituitary tumor, usually an adenoma.

Cushing's disease is responsible for roughly two thirds of the cases of endogenous Cushing's syndrome

hyperprolactinemia is seen with cushing's disease as a part of hypersecretary anterior pitutary or due to stalk compression.

Very Happy

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Dr Miss. Raj Walavalkar MBBS MRCOG
TealeFenning Administrator
SR O&G Wessex Region

EMAK · Century Club Joined: 26 Nov 2006 Posts: 572

Shinelkimo · Joined: 25 Apr 2007 Posts: 55

what medications can inhibit prolatin secretion?

cpeedahsa · Century Club Joined: 21 Apr 2007 Posts: 921

cpeedahsa · Century Club Joined: 21 Apr 2007 Posts: 921

cpeedahsa · Century Club Joined: 21 Apr 2007 Posts: 921

cpeedahsa · Century Club Joined: 21 Apr 2007 Posts: 921

Control of Prolactin Secretion

Contrast to other pituitary hormones, the hypothalamus tonically suppresses prolactin secretion from the pituitary. (Hypothalamic "brake" on lactotroph. So prolactin secreted when brake released.)
If the pituitary stalk is cut, prolactin secretion increases, (secretion of all the other pituitary hormones fall dramatically due to loss of hypothalamic releasing hormones. )

Dopamine -major prolactin-inhibiting factor/brake on prolactin secretion.
Dopamine secreted into portal blood by hypothalamic neurons, binds to receptors on lactotrophs, inhibits synthesis + secretion of prolactin.

Any agents and drugs that interfere with dopamine secretion or receptor binding lead to enhanced secretion of prolactin.

Also prolactin secretion is positively regulated by thyroid-releasing hormone, gonadotropin-releasing hormone and vasoactive intestinal polypeptide.

Nipple stimulation -prolactin release( spinal reflex arc that causes release of prolactin-stimulating hormones from the hypothalamus.)

Estrogens -positive control over prolactin synthesis+secretion. (Best example is - increasing estrogen in late pregnancy - elevated prolactin -prepare mammary gland for lactation at the end of gestation)

ACTH, CRH-- no role in regulation of prolactin secretion

cpeedahsa · Century Club Joined: 21 Apr 2007 Posts: 921

Maud · Joined: 11 Oct 2007 Posts: 73 Location: Bristol

I'm trying to work out whether Cushing's (syndrome or disease) is associated with endometrial hyperplasia. Cushing's is associated with obesity and hypertension, which are independant risk factors for hyperplasia (but are they "second cousins"?).
Cushing's is definitely associated with amenorrhoea, but is there unopposed oestrogen secretion or are the ovaries "blocked" altogether and no oestrogen secretion either?
The above discussion had left me more confused, as there doesn't seem to be consensus what Cushing's syndrome and disease are and what their affects are.
Sad

rpwalavalkar · Teale Fenning Administrator Joined: 20 Jul 2006 Posts: 966

Hey Maud,

you did make a good point there. I have been reading up about endometrial hyperplasia and Cushing's basic patho physiology --- they are 'second cousins' action is thru HPA axis derangement and also the obesity and HT will contribute in.

r
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Dr Miss. Raj Walavalkar MBBS MRCOG
TealeFenning Administrator
SR O&G Wessex Region