ISSN:
1741-0444
Keywords:
Force transducer
;
Frequency response
;
Isometric force development
;
Microtools
;
Simulation
;
Vascular smooth muscle cell
;
Video detection system
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract To measure forces of the order of 0·1 μN, generated by single isolated vascular smooth muscle cells, a sensitive transducer system has been developed. A video displacement detection system and an inductive position detector were used to control the tip displacement of a glass microneedle. The bending of the microneedle was used as a measure of the force generated by a single smooth muscle cell attached to the tip. During isometric contractions the stiffness of the system was 0·7 μN μm−1. A signal limiter in one of the feedback loops made it possible to reduce the stiffness of the system to 4 nN μm−1 when an adjustable force limit was exceeded. These two conditions of the system made it possible to measure both isometric and isotonic contractions of a single muscle cell. The force limiter may also be used to protect the preparation against excessive forces developed during contraction. A mechanical model of the system and the vascular smooth muscle cell was simulated and verified. The parameters of the model for a single vascular smooth muscle cell, two viscoelastic springs in parallel, could be estimated from the measurements. The bandwidth of the system during isometric contraction was 17 Hz.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02446815
