Why hyperthyroid hearts beat faster
Thyroid hormone regulation of beta-adrenergic receptor number.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Receptor number increased dramatically, but affinity for adrenaline remained unchanged.
Most assume more receptors means stronger binding—but here, the heart responds more because there are more receptors, not because each one grabs adrenaline tighter.
Practical Takeaways
If you have unexplained rapid heartbeat or anxiety, consider thyroid function as a possible biological contributor.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Receptor number increased dramatically, but affinity for adrenaline remained unchanged.
Most assume more receptors means stronger binding—but here, the heart responds more because there are more receptors, not because each one grabs adrenaline tighter.
Practical Takeaways
If you have unexplained rapid heartbeat or anxiety, consider thyroid function as a possible biological contributor.
Publication
Journal
The Journal of biological chemistry
Year
1977
Authors
L. Williams, R. Lefkowitz, A. M. Watanabe, D. Hathaway, H. R. Besch
Related Content
Claims (4)
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.
When rats have an overactive thyroid, their hearts have more receptors that respond to stress hormones, which might make their hearts beat harder and faster when those hormones are present.
Even when rats have too much thyroid hormone, their heart receptors still respond to certain chemicals the same way as normal rats—so the sensitivity of those receptors doesn’t change, even if there are more of them.
When your body has too much thyroid hormone, it makes your heart beat faster and makes you sweat more—even when you're not exercising or stressed out.