Receptor changes in the nucleus tractus solitarii of the rat after exercise training.
OBJECTIVE
The aim of the present study was to evaluate neurotransmitter receptor changes in the nucleus tractus solitarii (NTS) of the rat after exercise training.


METHODS
Twelve Wistar Kyoto rats were used. Six rats were submitted to a progressive training program in which they ran on a treadmill 5 d x wk(-1) for 13 wk (trained). The other rats were kept as controls (sedentary). After this period, the rats were killed and the brains processed for quantitative receptor autoradiography. Coronal brain sections were obtained using a cryostat and were incubated with a specific buffer solution containing [(3)H]vasopressin or (3)Hp-aminoclonidine.


RESULTS
In the NTS of the trained rats, a decrease in the values of binding parameters (IC(50) and K(D)) of vasopressin receptors was observed, indicating an increase in the affinity of vasopressin receptors. On the other hand, a decreased affinity was observed for alpha(2)-adrenoceptors in the NTS of the trained rats in comparison with the sedentary animals.


CONCLUSIONS
Exercise training leads to changes in vasopressin and alpha(2)-adrenoceptors, which may explain several physiological alterations occurring during physical activity.
De Souza
C G
CG
Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo 05508-900, Brazil.
Michelini
L C
LC
Fior-Chadi
D R
DR
D000818:Animals; D001345:Autoradiography; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D018341:Receptors, Adrenergic, alpha-2 / Q000032:analysis / Q000502:physiology*; D017483:Receptors, Vasopressin / Q000032:analysis / Q000502:physiology*; D017552:Solitary Nucleus / Q000293:injuries* / Q000502:physiology
D018341:Receptors, Adrenergic, alpha-2; D017483:Receptors, Vasopressin