Neuronal and cardiovascular responses to adenosine microinjection into the nucleus tractus solitarius

摘要: Abstract This study investigated neuronal, blood pressure, and heart rate responses to adenosine microinjection into caudal rostral NTS of anesthetized rats. The site recording was verified chemically by observing the a test dose l -glutamate (5 nmol) histologically at conclusion experiment. Neuronal firing increased (+29.4 ± 5.3%) decreased (−48 9.4%) in response NTS, respectively. These opposite neuronal were followed depressor (−32.4 8.3 vs. −36 5.5 mmHg ) bradycardic (−25.2 7.7 −25.8 3.4 beats / min two subareas NTS. Microinjection submaximal ( 1 produced site-dependent cardiovascular which preceded similar inhibition (−60 4 −55.9 1.7%). Whereas elicited modest pressor (+10.1 2.1 tachycardie (+9 3.9 responses, its (−29.2 5.3 (−14.6 1.7 responses. findings suggest that compared -glutamate, produces (rostral) (caudal) effects In (0.1, 1, 10 dose-related inhibitory attenuated systemic theophylline but not 8-(p-sulfophenyl) (8-SPT) administration. also 8-SPT same area. Finally, single-unit activity inhibited or baroreceptor loading excited unloading. 1. a) elicits NTS; 2. b) distinct hemodynamic may be related, least part, their differing -glutamate; 3. c) similarity between neurons activation support hypothesis plays neuromodulatory role processing information.