Morphological And Physiological Studyes On The Parabrachial Nucleus In The Rat

The parabrachial nucleus (PBN) surrounds the brachium conjunctivum along its course through the dorsolateral pons. It was first described by Winkler and Potter in the cat in 1914 and called the present name by Taber in 1961. According to the relative position of the neurons to the brachium conjunctivum the PBN was subdivided into lateral PBN (dorsal PBN) and medial PBN (ventral PBN) . Some authors also included the ventrolaterally situated kolliker-Fuse nucleus.The PBN had not been systematically studied until 1973. Connection studies showed that the PBN not only receives afferents from spinal cord, nucleus of the solitary tract, hypothalamus, amygdala and some other structures in the brain, but also sends efferents to wide areas of the CNS. The complexity of the neural connections indicates that the PBN has relatively complicated function. Increasing evidence suggests that the PBN plays an important role in a variety of visceral functions such as those related to taste, respiration, cardiovascular control, gastrointestinal activity, water balance, metablism, locomotor activity, sleep, emotional behavior, as well as, possibly, some neuroendocrine functions.So far it is still far away from the full understanding of the structure and function of the PBN. In the present study, we used Golgi silver impregnation, immunocytochemical staining (ABC procedure) , immunoelectron microscopy, retro- and anterograde HRP tract tracing, retrograde Fluorogold (FG) tract tracing, anterograde PHA-L tract tracing, double staining of HRP tract tracing and immunocytochemistry, double staining of FG tract tracing and immunofluorescence and electrophysiological analysis to attempt to have a further understanding of the PBN.The Sprague -Dawley rats were employed and Milner et al, Fulwiler and Saper's region demarcation and the subnuclear nomenclature of the PBN were...