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At least 19 recordsLinked to original sources
PubMed1964

HISTOCHEMICAL DEMONSTRATION OF UPTAKE OF EXOGENOUS NOREPINEPHRINE BY ADRENERGIC FIBERS IN VITRO.

Adrenergic fibers in isolated iris preparations were demonstrated histochemically by means of the formaldehyde condensation technique. In the presence of adenosine triphosphate (ATP) there was a net uptake of norepinephrine added in vitro by the adrenergic fibers producing a striking increase in fluorescence. In the absence of ATP only a slight increase in fluorescence was observed when the tissue was exposed to high concentrations of norepinephrine.

Adenosine Triphosphate↗
PubMedDate not supplied

Histochemical demonstration of adrenergic fibers in the fascia periosteum and retinaculum.

Adrenergic nerve fibers were demonstrated in the fascia, periosteum and retinaculum using the formaldehyde method of Falck--Hillarp and the recently developed glyoxylic acid method. A typical adrenergic plexus was seen around the vessels. The arteries and arterioles received a dense adrenergic nerve supply. The veins had a sparse adrenergic innervation and the venules and capillaries were apparently without adrenergic innervation. These distribution patterns of adrenergic fibers were fundamentally similar to those seen in various organs. A difference in the pattern of innervation was seen, however, in the arterioles betweeen the fascia, and periosteum and retinaculum. Furthermore, chemical sympathectomy induced by injection of 6-hydroxydopamine resulted in the disappearance of noradrenaline fluorescence and marked vasodilation in the fascial vascular bed, and a moderate vasodilation in the periosteum and retinaculum. These findings suggest that the role of adrenergic fiber is vasoconstrictor and these fibers regulate the circulation in the fascia, periosteum and retinaculum.

Adrenergic Fibers↗
PubMedDate not supplied

[Seasonal changes in the adrenergic fibers in the wall of the microvessels of the cheek pouch of the hamster, Mesocricetus auratus].

Adrenergic innervation has been investigated by fluorescent histochemical method with glyoxylic acid. Adrenergic fibers were found in summer period on the arterioles with a diameter varying from 100 to 30 micron, their fluorescence being significantly lower than that in the vessels of microcirculatory bed of the mesentery, tongue, femoral muscles of the same animal. No adrenergic fibers were revealed on the arterioles with a smaller diameter, on veins and venules. In winter period, fluorescence is completely absent from all the vessels of the cheek pouch, which may be due to the decrease in the level of catecholamines in the nerves and other tissues during hibernation.

Adrenergic Fibers↗
PubMed1988

Interaction between adrenergic fibers and intermediate cholinergic neurons in the rat spinal cord: a new double-immunostaining method for correlated light and electron microscopic observations.

Relationships between cholinergic neurons and adrenergic fibers in the intermediate region of the rat thoracic spinal cord were examined using a new immunohistochemical double-staining method for light and electron microscopic observations. Cholinergic neurons were labeled by a monoclonal antibody to choline acetyltransferase and stained bluish green by 5-bromo-4-chloro-3-indolyl-beta-D-galactoside reaction products using beta-galactosidase as a marker. On the same sections, adrenergic fibers were labeled by a polyclonal antiserum to phenyl-ethanolamine-N-methyltransferase and stained brown by diaminobenzidine reaction products using peroxidase as a marker. After embedding in Epon, the sections were examined in the light and electron microscopes. In the light microscope, choline acetyltransferase-like immunoreactive cells were seen in the four discrete areas of the intermediate region: the principal intermediolateral nucleus, the central autonomic nucleus, the intercalated nucleus and the funicular intermediolateral nucleus. These cell groups seemed to be connected to each other by their processes, and they showed a "ladder-like appearance" as a whole. Phenylethanolamine-N-methyltransferase-like immunoreactive fibers were present only along this "ladder-like structure" and were the most rich in the principal intermediolateral nucleus. In the electron microscope, some of the choline acetyltransferase-like immunoreactive neurons, which were identified by light micrographs, were found to receive synaptic inputs from phenylethanolamine-N-methyltransferase-like immunoreactive boutons in the principal intermediolateral nucleus. These findings suggest that the adrenergic axons in the principal intermediolateral nucleus directly affect the activity of the cholinergic preganglionic sympathetic neurons.

Adrenergic Fibers↗
PubMed1989

[Confirmation of the presence of adrenergic fibers in human umbilical cord by electron microscopy].

1) In order to visualize biogenic catecholamine, the FAGLUPAGAS method, a new modification of the glyoxylic acid method, was used. Catecholaminergic fibers were observed chiefly in the intraarterial and surrounding region of arteries within Wharton's jelly. Periarterial plexus formation was also observed only in part of the umbilical cord near the umbilical ring. 2) Because first of all we had succeeded in detecting longitudinally running catecholaminergic fibers forming a periarterial plexus, we were able to prepare ultrathin sections exactly parallel to such fibers, and succeeded in confirming the presence of adrenergic fibers in human umbilical cord by electron microscopy.

Adrenergic Fibers↗
PubMedDate not supplied

Ontogeny of adrenergic fibers in rat spinal cord in relationship to adrenal preganglionic neurons.

Adrenergic neurons in the C1 cell group in the rostral ventrolateral medulla oblongata contain epinephrine, as well as its biosynthetic enzyme, phenylethanolamine N-methyltransferase (PNMT). These neurons send axons to regions of the central nervous system known to regulate autonomic function, including the sympathetic preganglionic nuclei of thoracic and upper lumbar spinal cord. Previous studies have shown that PNMT is expressed in neurons located in the medulla oblongata on embryonic day 14; however, the development of the projections from these cells has not been studied. With the aid of high-performance liquid chromatography (HPLC) to determine levels of catecholamines and immunocytochemistry to demonstrate PNMT, the ontogeny of the adrenergic bulbospinal pathway in the embryonic, postnatal, and adult rat has been studied. In addition, the relationship between PNMT-immunoreactive (IR) fibers and retrogradely labeled sympathetic preganglionic neurons projecting to adrenal medulla are described. PNMT-IR fibers were first observed in the caudal medulla oblongata and lateral funiculus of spinal cord on gestational day 15(E15). On E16, PNMT-IR fibers in the thoracic spinal cord were observed in the intermediate gray matter at the level of the lateral horn. Epinephrine was measureable in spinal cord on E20. Both the density of PNMT-IR fibers and the levels of epinephrine increased to a maximum during the second postnatal week and then declined to adult levels. These observations suggest that a period of adrenergic hyperinnervation of spinal sympathetic nuclei occurs during the neonatal period. PNMT-IR terminals in spinal cord were observed, primarily, although not exclusively, in sympathetic nuclei of thoracic cord and parasympathetic nuclei of upper sacral cord. Adrenergic fibers in the intermediolateral nucleus (IML) and the central autonomic nucleus (CAN) dorsal to the central canal were particularly dense during the second postnatal week in both midthoracic and upper sacral segments. In the neonate, a "ladder-like" pattern of PNMT-IR fiber staining was observed which represented transverse fiber bundles connecting IML with CAN and extensive longitundinal fiber bundles along the border of the funiculus in IML. At all spinal levels, adrenergic fibers were also observed adjacent to the ependyma dorsal or lateral to the central canal. The relationship between adrenal preganglionic neurons and PNMT-IR fibers in IML was examined on postnatal days 4, 15, and 60. With retrograde labeling from adrenal medulla, it was demonstrated that PNMT-IR fibers are associated with adrenal preganglionic neurons throughout postnatal development.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenal Glands↗
PubMed1989

Adrenergic fibers in the spinal cord of the monkey: light and electron microscopic study.

The adrenergic innervation of the monkey (Macaca fascicularis) thoracic spinal cord was examined by means of peroxidase-antiperoxidase immunohistochemical method using antisera directed phenylethanolamine N-methyl transferase (PNMT). At light microscopic level the PNMT-positive profiles are seen as brown granules, presumably axon terminals, or varicose fibers. They are localized in the intermediolateral nucleus, central gray and the intermediate gray which connects the two. Occasional fibers are seen in ventral and dorsal horns. The descending adrenergic fiber tract is found in the lateral margin of the lateral funiculus. At electron microscopic level, the PNMT-positive presynaptic profiles exhibit densely packed small clear vesicles, a few large dense core vesicles and numerous mitochondria. They make synaptic contact with dendritic profiles (97%) and somatic profiles (3%) and demonstrate either symmetric or asymmetric synaptic specialization. The descending adrenergic fiber tract consists mainly of unmyelinated fibers and is located in the ventral half of the lateral funiculus.

Adrenergic Fibers↗
PubMed1991

Increased density of fluorescent adrenergic fibers around the middle cerebral arteries of stroke-prone spontaneously hypertensive rats.

The distribution of fluorescent adrenergic nerve fibers in the proximal portion (horizontal segment, Hs) and the three distal portions (major branches) of the middle cerebral arteries (MCA) was examined in stroke-prone spontaneously hypertensive rats (SHRSP) aged 10, 30, 60, 90, and 180 days, by the glyoxylic acid method. The results were compared with those in age-matched normotensive Wistar Kyoto (WKY) rats. While the distribution pattern of fluorescent nerve fibers in the proximal portion of WKY rats changed from a straight linear arrangement at 10 and 30 days of age to a network-like arrangement after 60 days, those from SHRSP showed a constant meshwork pattern throughout the entire examination period. In the distal portions of the MCA of both SHRSP and WKY rats at all ages examined, fluorescent nerve fibers formed a coarse network. The distribution densities of adrenergic nerve fibers in the proximal and distal portions of the MCA of SHRSP were significantly higher (P less than 0.01 and 0.05) than those of WKY rats at all ages examined, except in the proximal portion at 90 and 180 days of age. The difference in nerve fiber density between SHRSP and WKY rats reached a peak at 30 days of age in both proximal and distal portions, and then gradually decreased with age. The present study suggests that sympathetic hyperinnervation is an important factor in the development of hypertension, and is involved in its maintenance in SHRSP.

Adrenergic Fibers↗
PubMedDate not supplied

[Origin and the functional role of adrenergic fibers of the vagus nerve in cats].

Origin of adrenergic fibres of vagus is studied. They are shown to appear in the thoracic vagus through caudal anastomosis introduction. The observations indicated that axons of spinal neurons and neurons of the ganglion stellate passed through caudal anastomosis and entered a thoracic vagus nerve. Stimulation of the thoracic vagus in cats after atropine sulphate injection increases the heart rate.

Adrenergic Fibers↗
PubMed1984

[Adrenergic fibers in the suspensory system of the ovary in the swine].

The purpose of this paper was to study adrenergic innervation of mesovarium in the pig. The studies were carried out on material from 5 immature sows weighing about 35 kg of the Polish large white breed. The mesovaria taken were stretched on microslides of Cimble type and treated with glyoxylic acid. After filtering off the excessive reagent, drying and roasting at 80 degrees C, the preparations were examined under the fluorescence microscope. For adrenergic nerves, according to the cryteria commonly used, only those were taken which demonstrated green fluorescence. In the suspensory apparatus of ovarium in the pig the presence of numerous adrenergic nerves was found, which, because of their location and course, can be divided into two groups: adrenergic nerves the course of which is associated with that of blood vessels and those running independently in mesovarium. The studies have shown that mesovarium and ovarium of the pig are richly innervated with adrenergic nerves.

Adrenergic Fibers↗