The Claim
Exposure to exogenous thyroid hormones (thyroxine and triiodothyronine) in rats is associated with a 120% increase in the number of beta-adrenergic receptor binding sites in heart tissue, rising from 89 ± 5 to 196 ± 7 fmol/mg of protein, without altering receptor affinity for dihydroalprenolol or isoproterenol, suggesting thyroid hormones modulate receptor density rather than binding strength.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When rats are given thyroid hormones, their heart cells develop about twice as many spots where adrenaline-like chemicals can attach, but the spots don’t change how tightly they hold onto those chemicals—so it’s like adding more hooks, not making the hooks stronger.
See the scientific wording
Exposure to exogenous thyroid hormones (thyroxine and triiodothyronine) in rats is associated with a 120% increase in the number of beta-adrenergic receptor binding sites in heart tissue, rising from 89 ± 5 to 196 ± 7 fmol/mg of protein, without altering receptor affinity for dihydroalprenolol or isoproterenol, suggesting thyroid hormones modulate receptor density rather than binding strength.
What the research says
1 studyStudy: Thyroid hormone regulation of beta-adrenergic receptor number.
The study found that giving rats extra thyroid hormones made their heart cells have many more spots where adrenaline can attach, but those spots didn’t change how tightly they held onto adrenaline. This matches exactly what the claim says.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.