The thyrotropin receptor (or TSH receptor) is a receptor (and associated protein) that responds to thyroid-stimulating hormone (also known as "thyrotropin") and stimulates the production of thyroxine (T4) and triiodothyronine (T3).
The thyrotropin receptor (TSHR) is a protein that responds to thyroid-stimulating hormone (TSH), leading to increased production of thyroxine (T4) and triiodothyronine (T3).