The nucleus of the tractus solitarius of the dog. A morphological and morphometric analysis.

The neuronal and fibrous architecture of the nucleus of the tractus solitarius (NTS) of the dog has been studied in transversely cut Nissl, myelin and reduced silver stained serial sections. Eight distinct subdivisions, clearly delimited both by their cytoarchitectonic and fibrous characteristics, have been identified. They are: the commissural, gelatinous, lateral, interstitial, dorsolateral, ventrolateral, intermediate and medial subdivisions. Their rostrocaudal extensions and locations in relation to the obex are summarised in Table 1. A morphometric analysis was additionally done. The frequency distributions of cell areas and cell form factor of each subdivision are represented by histograms in Figures 8 and 9 respectively.

Macroscopical and microscopical anatomy of the hippocampus in the dog.

In this article we have studied the topography, relationship and projection of the hippocampus in the dog by means of 1 mm thick transverse, horizontal and parasagital sections stained with Mulligan's reagent and 50 microns transverse sections (Nissl). The macroscopical disposition of this part of the CNS was completed by means of a gross dissection. Horizontal sections of 10 microns through the middle or limbic part were used to determine the general microscopic anatomy and to define the morphometry of its cells. From this point of view the Hippocampus of the dog appears to be intermediate between the rat and primates, species better studied.