In: Anatomy and Physiology
If a pituitary adenoma secretes excessive amounts of prolactin, levels of which of the following hormones will be elevated?
TRH |
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TSH |
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thyroid hormone |
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none of the above |
Which of the following will occur if the thyroid is unable to secrete thyroid hormones?
excessive PRL secretion will make TRH levels abnormally low |
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excessive TRH secretion will stimulate PRL secretion |
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TSH will stimulate PRL secretion |
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PRL will stimulate TSH secretion |
Which of the following hormones does not exert an inhibitory influence on the secretion of another hormone as part of a negative feedback mechanism?
PRL |
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TRH |
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thyroid hormone |
Which of the following would be the best choice for treating a patient with a hyperprolactinemia that resulted from a non-functioning thyroid?
administration of a dopamine agonist |
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a TSH antagonist |
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TRH injuction |
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administration of thyroid hormones |
Which of the following would be the best choice for treating a patient with a hypothyroidism caused by a PRL secreting adenoma?
TRH injection |
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administration of a dopamine agonist |
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administration of thyroid hormones |
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a TSH antagonist |
The semilunar valves are open throughout which of the following stages?
isovolumic relaxation |
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isovolumic contraction |
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ejection |
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passive filling |
The semilunar valves open at the end of which of the following stages?
isovolumic relaxation |
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passive filling |
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isovolumic contraction |
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ejection |
All four valves are shut during which of the following stages?
isovolumic contraction |
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passive filling |
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ejection |
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active filling |
All four chambers are relaxed during which of the following?
ejection |
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isovolumic contraction |
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passive filling |
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active filling |
1) TRH (Thyrotropin releasing hormone)
The prolactinoma is caused due to the formation of benign tumor in the pituitary gland and hence it stimulates the increase production of milk due to the increase in secretion of prolactin. It is found that due to the formation of the pituitary adenoma, it leads to hypothyroidism which causes decrease in the production of thyroid hormones. When one is suffering from pituitary adenoma, it is found that it increases the release of the TRH or thyrotropin releasing hormone which is produced by hypothalamus. This hormone helps in increasing the release of thyrotropin as well as prolactin from the pituitary gland.
The second option is not correct because pituitary adenoma tends to cause hypothyroidism in which there is decrease in the production of the thyroid hormone. Due to the increase in the tumor size within the pituitary gland, it leads to decreased production of TSH or thyroid stimulating hormone.
The third option is not correct because pituitary adenoma leads to decrease production of thyroid hormone and this is because it is not able to produce enough thyroid stimulating hormone. Hence it is responsible for causing hypothyroidism.