Endothelin-1 may act as a negative inotropic agent in cardiac myocytes from young and senescent rats.
The contractile response to Endothelin-1 (ET-1) has been investigated in electrically stimulated single cardiac myocytes isolated from hearts of young and senescent rats. ET-1 (0.1-10 nM) exhibited a marked negative inotropic effect in both age groups. ET-1 (1.0 nM) also reduced the occurrence of spontaneous contractile oscillations in young myocytes, suggesting depletion of sarcoplasmic reticulum-Ca(2+) stores. The possibility that ET-1 may have opposite effects on myocardial contractility is discussed.
Fraticelli
A
A
Laboratory of Experimental Cardiology, I.N.R.C.A., Via della Montagnola 164, Ancona, Italy.
Rossi
L
L
Socillo
A I
AI
Boria
C
C
Capogrossi
M C
MC
Paciaroni
E
E