NBME 20 Tissue: testicle; Effect: estradiol production (NBME Answers)

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NBME 20 Answers

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A 32-year-old man comes to the physician ...
Tissue: testicle; Effect: estradiol production 🔍 / 📺 / 🌳 / 📖
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+9 upvote downvote
submitted by ∗step420(32)

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B-HCG and LH,FSH,TSH share same alpha subunit, so HCG can activate those receptors if its in high enough quantity. Activating LH receptor will lead to more Testosterone from the Leydig cells. More testosterone can lead to more estrogen formation via aromatase.

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dickass bHCG directly increases testicular aromatase activity, it's not because of the increased amount of testosterone. +6

vulcania And for those who were wondering (cause I was), Sertoli cells have aromatase (FA 2019 p. 614) +10

godby It's a slightly different question, on the stem, what's the purpose of the hCG to him, for infertility or increased sexual demand ? Just curious. +

+1 upvote downvote
submitted by ∗divya(75)

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uworld q id - 582 for reference gonadotropins increase aromatase activity.

Aromatase activity is increased by - 1) age 2) obesity 3) insulin 4) gonadotropins 5) alcohol

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submitted by ∗dickass(127)

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Testicles have significant aromatase activity. This enzymatic activity is regulated by LH (and of course bHCG)

https://www.ncbi.nlm.nih.gov/pubmed/9267128

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+0 upvote downvote
submitted by ∗trazobone(97)

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For anyone who was like me and clicked Liver Testosterone Metabolism, yes you would see gynecomastia in a liver pathology, but that’s because the liver metabolizes ESTROGEN not testosterone, leading to an overall imbalance of estrogen:testosterone levels.

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