Hormones 2016

Prothrombin - PT
Elevated prolactin may be associated with corpus luteum insufficiency
or anovulation. Sequelae of hyperprolactinemia include amenorrhea,
anovulation, and decreased bone density.
When determining prolactin, it should be remembered that the measured
concentration is dependent upon when the blood sample was taken, since
the secretion of prolactin occurs in episodes and is also subject to a 24-hour
cycle.
The release of prolactin is promoted physiologically by suckling and stress.
In addition, elevated serum prolactin concentrations are caused by a
number of pharmaceuticals (eg, dibenzodiazepines, phenothiazine), TRH,
and oestrogen (Frantz, 1978), (Müller et al., 1983), (Pontiroli, Falsetti, and
Bottazzo, 1987). The release of prolactin is inhibited by dopamine, L-dopa,
and ergotamine derivatives.
Antipsychotic drugs may elevate serum prolactin. Antipsychotics block
dopamine, thereby elevating serum prolactin levels. Hyperprolactinemia
is present in many patients receiving neuroleptics with an occasional
patient developing amenorrhea, galactorrhea, and/or decreased libido.
Amoxapine, a dibenzoxazepine type of tricyclic with antidepressant
and antipsychotic characteristics, has been found to cause galactorrhea
and oligomenorrhea with hyperprolactinemia. Amoxapine may have a
dopamine blocking action (Gelenberg et al., 1979). The prolactin level may
rise significantly but only briefly.
Persistent elevations of plasma prolactin levels may be observed with, and
after withdrawal from, chronic cocaine abuse, and may reflect a cocaineinduced
derangement in the neural dopaminergic regulatory systems
(Mendelson et al., 1988).
Prothrombin - PT
A prothrombin time test measures how quickly your blood clots. Sometimes
called a PT or pro time test, a prothrombin time test uses a sample of your
blood.
Prothrombin is a protein produced by your liver. It is one of many factors
in your blood that help it to clot appropriately (mayoclinic, 2015a).
Results
Prothrombin time test results can be presented in two ways.
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Version 2016.3576– – Document LATEXed – 1st May 2016
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