Supports· strongVASO-E003
The latch-bridge model: force maintained after activation falls
- what the source states
- A minimum kinetic model of smooth-muscle cross-bridge interaction in which dephosphorylated but still-attached cross-bridges ("latch bridges") detach only slowly, reproducing the experimental observation of high sustained stress at low levels of myosin phosphorylation — economical force maintenance after activation subsides.
- what we infer
- Biology ships a cheap, history-dependent hold: the mechanism the featured hypothesis needs exists and is textbook physiology. Whether it is engaged at tender points is a separate, untested question.
- limitations
- Established in vascular/visceral smooth-muscle preparations over minutes-to-hours timescales; indefinite in-vivo holds at addressable sites are an extrapolation.
- Molecular interpretation still under refinement (regulated phosphatase activity, cooperativity).