Over 30 nuclei have been identified in the reticular formation of rats, but only a small number of distinct reticular nuclei have been recognized in frogs. We used immunohistochemistry, retrograde tracing, and cell morphology to identify nuclei…
In response to a brief vagal stimulus, the atrial rate initially slows, then transiently accelerates, and slows a second time. We determined the effects of three antagonists to two ionic channels on this characteristic triphasic pacemaker response.…
The positive chronotropic and inotropic effects of vasoactive intestinal peptide, VIP, were studied in an isolated canine right atrial preparation, Atria were removed, maintained in a bath, and perfused with Tyrode's solution. Contractile force and…
Projections from medial agranular cortex to brain stem in rat were determined by use of the anterograde tracers Phaseolus vulgaris leucoagglutinin, or wheat germ agglutinin conjugated horseradish peroxidase. Axonal trajectories were also followed by…
Brainstem reticular nuclei of amniotes (mammals, birds and reptiles) may share a common phylogenetic origin as demonstrated by their many shared features (hodology, cytoarchitectonics, presence of neurochemicals). By studying characteristics of these…
Substance P (SP) is abundant in the carotid sinus nerve (CSN) and has been implicated in baro- and chemoreceptor reflexes. We examined the effect of SP on blood pressure, heart rate, phrenic nerve activity, hindlimb perfusion pressure, and cardiac…
The reticular formation of mammals contains numerous nuclei which can be recognized by their projection patterns, cytoarchitectonics, and neuropeptide/neurotransmitter content. We have identified reticular nuclei in representatives from numerous…
Activity was recorded from physiologically identified baroreceptor or chemoreceptor fibers in carotid sinus nerves of urethane-anesthetized spontaneously breathing rabbits. A carotid sinus area was vascularly isolated so that carotid sinus pressure…
The distribution of cells which were immunohistochemically positive for leu-enkephalin (LENK+) or serotonin (5-HT+), two substances widely distributed in the reticular formation, was determined in two species of skates (Raja binoculata and Raja…
The central nervous system location of neurochemicals that are widely distributed among extant animals may give us clues to changes that occurred in the brains of these animals during evolution. We have been studying the brains of cartilaginous…
Substance P (SP) levels in the spinal cords of very old rats are less than the levels in younger rats (Bergman et al., 1996). After injury to a peripheral nerve in young rats, immunoreactivity (ir) to the SP receptor, NK-1 (neurokinin-1), increases…
Nerve injury may lead to chronic neuropathic pain syndromes. We determined whether the extent of central nervous system microglial activation that accompanies nerve injury is age dependent and correlated with behavioral manifestations of pain. We…
