Adenosine A1 receptor distribution in the nucleus tractus solitarii of normotensive and spontaneously hypertensive rats.
Adenosine acts at many sites to modulate neuronal activity. The nucleus tractus solitarii (NTS) is a major brain site in cardiovascular control. The present study was undertaken for a detailed analysis of the distribution of A(1) adenosine receptor (A(1)R) in the NTS of spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY), using in vitro autoradiography with [(3)H]DPCPX. The density of [(3)H]DPCPX in the whole NTS decreased according to the rostral-caudal levels. This high level of [(3)H]DPCPX binding at rostral sites is due to an specific label of the dorsomedial/dorsolateral subnuclei. On the other hand, analysis of subpostremal subnucleus, showed opposite results. The density of [(3)H]DPCPX binding in the subpostremal NTS increased according to the rostral-caudal levels. Furthermore, it was observed an increased [(3)H]DPCPX binding in the SHR compared with WKY. The results show a complex pattern of A(1)R distribution in the NTS, which highlight the powerful modulatory actions mediated by adenosine in the NTS barosensitive neurons.
Carrettiero
D C
DC
Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil.
Fior-Chadi
D R
DR
D058917:Adenosine A2 Receptor Antagonists; D000818:Animals; D001345:Autoradiography; D007091:Image Processing, Computer-Assisted; D008297:Male; D009928:Organ Specificity; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D043705:Receptor, Adenosine A2A / Q000378:metabolism*; D017552:Solitary Nucleus / Q000378:metabolism*; D014316:Tritium; D014970:Xanthines / Q000493:pharmacokinetics
D058917:Adenosine A2 Receptor Antagonists; D043705:Receptor, Adenosine A2A; D014970:Xanthines; D014316:Tritium; C051360:1,3-dipropyl-8-cyclopentylxanthine