Activation of the central cholinergic pathway increases post-exercise tail heat loss in rats.
The aim of this study was to evaluate the effects of stimulation of the central cholinergic pathway on the regulation of post-exercise tail heat loss in rats. Either 2.0microL of 25x10(-3)M physostigmine (Phy) or 0.15M NaCl solution (Sal) were injected into the right lateral cerebral ventricle of both resting (n=8) and post-exercising rats (n=6; 24mmin(-1); 25min; 5% inclination). Tail temperature (Ttail) was measured using a thermistor taped to the tail, and intraperitoneal temperature, an index of core temperature (Tc), was recorded using a telemetry sensor implanted into the peritoneal cavity. In resting rats, Phy induced an increase in both Ttail (26.8+/-0.3 degrees C Phy versus 25.2+/-0.6 degrees C Sal; P<0.05) and in heat loss index (0.26+/-0.03 Phy versus 0.14+/-0.05 Sal; P<0.05; 30min after injection), and a decrease in Tc compared to the Sal injection group (36.6+/-0.2 degrees C Phy versus 37.0+/-0.2 degrees C Sal; P<0.05). In post-exercising rats, Phy injection attenuated the decrease in both T(tail) (28.3+/-0.8 degrees C Phy versus 26.4+/-0.6 degrees C Sal; P<0.05) and heat loss index (0.37+/-0.07 Phy versus 0.19+/-0.02 Sal; P<0.05) without altering Tc. We conclude that activation of the central cholinergic pathway increases post-exercise tail heat loss in rats.
Prímola-Gomes
Thales N
TN
Laboratory of Exercise Physiology, Department of Physical Education, School of Physical Education, Physical Therapy, and Occupational Therapy, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil.
Pires
Washington
W
Rodrigues
Luiz O C
LO
Coimbra
Cândido C
CC
Marubayashi
Umeko
U
Lima
Nilo R V
NR
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D001833:Body Temperature Regulation / Q000502:physiology*; D002800:Cholinesterase Inhibitors / Q000494:pharmacology; D007276:Injections, Intraventricular / Q000379:methods; D008297:Male; D010805:Physical Conditioning, Animal; D010830:Physostigmine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D012881:Skin Temperature / Q000502:physiology; D013623:Tail / Q000502:physiology*
D002800:Cholinesterase Inhibitors; D010830:Physostigmine; D000109:Acetylcholine