A computer program for motion analysis of single cardiac myocytes.
Single adult cardiac ventricular cells were prepared by collagenase perfusion of a rat heart. They were stimulated electrically in a perfusion chamber and their length changes were followed under a microscope. The motion was followed via a video camera and by a TV-line counting device and was recorded on-line by a personal computer. The program RECORD was used to calculate peak amplitude, base line drift and peak width at different peak heights allowing the determination of a number of variables of the cellular motion. The method was applied to drugs affecting the amplitude of contractions and the speed of relaxation. Results of beta-adrenergic stimulation, muscarinic inhibition and of the Ca(2+)-ATPase inhibitor cyclopiazonic acid (CPA) are shown. Besides its stimulatory effect on length, the beta-adrenergic agonist isoprenaline concentration-dependently shortened relaxation time. Carbachol reversed the increase in cellular shortening caused by isoprenaline in a concentration-dependent manner without fully reversing the shortened relaxation. CPA prolonged the return to diastole, presumably due to its inhibition of Ca(2+)-reuptake into the sarcoplasmatic reticulum.
Rüegg
U T
UT
Sandoz Pharma Ltd, Basle, Switzerland.
Zuber
J F
JF
Best
R
R
D000818:Animals; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000166:cytology*; D051381:Rats; D017208:Rats, Wistar; D012815:Signal Processing, Computer-Assisted; D012984:Software; D014741:Video Recording