Parameters affecting microinjections of adenosine into the brainstem of rats

It is well established that the Nucleus Tractus Solitarius (NTS) is the major relay nucleus for afferent input from baroreceptors and thereby plays a critical role in central cardiovascular control. A variety of neuroactive substances elicit potent cardiovascular responses following microinjection into the NTS. Since the issue of localization is very important in these studies, the aim of the present study was to examine the technical parameters of administering adenosine, a putative neuromodulator, via microinjection into the NTS. The results show that injection parameters are consequential and that adenosine elicits potent cardiovascular responses following microinjection into the NTS.