DETECT mRNAs ENCODING PREPROENKEPHALIN A IN THE ADRENAL GLANDS USING THE TECHNIQUE OF IN SITU HYBRIDIZATION HISTOCHEMISTRY / 解剖学报

cDNA probes encoding preproenkephalin A (PPA) were used to detect the mRNA codings within the sections of adrenal glands of guinea pigs, processing according to the following procedures; perfused the animals with Zambonis' or 4% paraformaldehyde fixative; rinsed the block of adrenal glands for 12 hours in O.1mol/L phosphate sodium solution; the block were cut at -15℃ in a cryostat; Then the sections were prehybridized and hybridized with the biotinylated cDNA encoding PPA. The sections were incubated in the solution containing streptavi- din-biotinylated HRP and chromostained with DAB. The positive reactive produ- cts appeared in the cytoplasm of about 90% of adrenal medullary cells.

DISTRIBUTION OF SEROTONIN, PHENYLETHANOLAMINE-N-METHYLTRANSFERASE SUBSTANCE P AND LEU-ENKEPHALIN IMMUNOREACTIVE NEURONS IN THE ROSTRAL VENTROLATERAL MEDULLA OF THE CAT / 解剖学报

The distribution of serotonin(5-HT), phenylethanolamine-N-methyltransferase (PNMT), substance P(SP) and leu-enkephalin(L-ENK) immunoreactive neurons in the rostral ventrolateral medulla (RVL) of the cat was studied with the immunohistochemical ABC technique, and the projection of 5-HT, SP and L-ENK positive neurons of the RVL into the thoracic cord was preliminarily investigated by a combined fluorescent retrograde transport and immunofluorescence method. The results indicate that 5-HT, PNMT, SP and L-ENK immunoreactive neurons mentioned above were localized primarily in the caudal part of nucleus paragigantocellularis lateralis and the rostral part of nucleus lateralis reticularis. SP positive cell bodies in the reticular formation close ventrolateral to nucleus ambiguus were also found. Some 5-HT, SP and L-ENK positive cells were situated in the area near the pia mater. In the most area of the RVL, 5-HT, PNMT, SP and L-ENK immunoreactive cell bodies had an overlapping distribution. 5-HT or PNMT or L-ENK positive neurons crowded, intertwined each other with their processes in the region at the levels 1.0-3.5mm caudal to trapezoid body, about 3.3mm lateral to the midline and about 0.8mm from the ventral surface of the medulla, and formed a longer or shorter continuous cell column which ran in the rostrocaudal direction. These three columns nearly coincided with each other at the level 1.5-2.5mm caudal to trapezoid body. Part of 5-HT, SP and L-ENK positive neurons in the RVL projected into the thoracic cord. The functional significance of these substances in the RVL was also discussed.

THE EFFERENT PROJECTIONS OF THE ROSTRAL VENTROLATERAL MEDULLA TO THE HYPOTHALAMIC PARAVENTRICULAR NUCLEUS AND THE THORACIC CORD IN THE CAT / 解剖学报

The efferent projections of the rostral ventrolateral medulla(RVL) to the hypothalamic paraventricular nucleus(Pa) and the thoracic cord were studied in the adult cat by using WGA-HRP or fluorescent retrograde tract-tracing method. After injection of WGA-HRP or fluorescent tracer Fast blue(FB) into one side of the Pa, retrogradely labelled cells were found in bilateral RVL, with an ipsilateral predominance. The labelled cells decreased in number from the caudal to the rostral level. After injection of FB into one side of the thoracic cord at T_2-T_3 segments, retrogradely labelled cells in the RVL were observed which increased in number from the caudal to the rostral level and reached the peak at 1.0-1.5mm caudal to the trapezoid body. Most of these cells were distributed in the ipsilateral RVL, and clustered in the region 0.0-1.0mm from the ventral surface of the medulla. After Diamino yellow 2HC1 and FB were injected into the Pa and the thoracic cord respectively, only single labelled cells were detected in the RVL, no double labelled cells were found. The above results suggest that the Pa and the thoracic cord receive separate fiber projections from different cells of the RVL.