Effects of nandrolone decanoate on respiratory and peripheral
muscles in male and female rats.
Bisschop, Anja, Ghislaine Gayan-Ramirez, Helene Rollier, P. N. Richard
Dekhuijzen, Rene Dom, Vera De Bock, and Marc Decramer.
Respiratory Muscle Research Unit, Laboratory of Pneumology and
Respiratory Division, Faculty of Physical Education and
Physiotherapy, and Department of Neuropathology, Katholieke
Universiteit Leuven, B-3000 Leuven, Belgium
APStracts 3:0561A, 1996.
Thirty male and eighteen female adult rats received weekly an i.m.
injection of either saline (Control, C), 1.5 (Low dose, LD) or 7.5
mg/kg (High dose, HD) nandrolone decanoate during 5 weeks. Compared
to respective C, growth rate was stunted in male HD rats from 2 weeks
of treatment on, while enhanced in female LD and HD rats already
after one week. Mass of all muscles studied varied proportionally to
body weight, except for the gastrocnemius (males:0.49+/-0.04 vs.
C:0.52+/-0.03 %, NS; females:0.17+/-0.01 vs. C:0.15 +/-0.01%,
P<0.05). In vitro contractile and fatigue properties of the
diaphragm remained unchanged, besides a decrease in twitch kinetics
(time to peak tension= C: 21+/-2, LD: 19+/-1, HD: 19+/-2 ms, P
< 0.05; half-relaxation time= C: 26+/-5, LD: 25+/-5, HD: 23+/
-3 ms, P < 0.01). Histochemistry of the diaphragm and the
gastrocnemius revealed a significant increase in type IIx/b
dimensions. In the gastrocnemius additionaly type I fiber dimensions
increased. A pair-fed study, including another 24 female rats, showed
that the changes in oral food intake only partly accounted for the
observed anabolic effects.
Received 7 June 1994; accepted in final form 12 November 1996.
APS Manuscript Number A562-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996