Co-localization of NOS and NMDA receptor in esophageal premotor neurons of the rat

Nitric oxide (NO) production following NMDA receptor stimulation plays a role in signaling between neurons. Using trans-synaptic tracing with pseudorabies virus (PRV), immunocytochemistry and histochemistry, we have demonstrated the expression of NMDAR1 and nitric oxide synthase (NOS) within brain stem neurons controlling esophageal peristalsis. PRV-immunoreactive second order esophageal premotor neurons of the central subnucleus of the nucleus of the solitary (NTScen) expressed NMDAR1 and NOS. First order motoneurons of the compact formation of the nucleus ambiguus (NAc) expressed NMDAR1, but did not contain NOS. NTScen neurons may synthesize and release NO in response to NMDA activation, suggesting a role for NO in the coordination of esophageal motility.

Transsynaptic localization of pharyngeal premotor neurons in rat

We determined the anatomy and connectivity of the brainstem circuit controlling the buccopharyngeal phase of swallowing, using pseudorabies virus to identify linked circuits of neurons. Pharyngeal vagal afferents terminate on premotor neurons in the interstitial and intermediate subnuclei of the nucleus of the solitary tract, which in turn, innervate pharyngeal motoneurons in the semicompact subnucleus of the nucleus ambiguus. This circuit is separate and distinct from the esophageal swallowing circuit.

Localization of nitric oxide synthase in the brain stem neural circuit controlling esophageal peristalsis in rats

BACKGROUND/AIMS

The central subnucleus of the nucleus of the solitary tract has been implicated in central reflex control of esophageal peristalsis. This study determined the presence of nitric oxide synthase in the brain stem circuit controlling esophageal peristalsis by combining transsynaptic retrograde tract tracing with pseudorabies virus and nicotinamide adenine dinucleotide phosphate diaphorase (NADPH) histochemistry.

METHODS

Virus was injected into the esophagus of 10 of 15 rats. After 60-63 hours, brain sections were processed for viral immunofluorescence and NADPH histochemistry.

RESULTS

Fluorescent neuronal labeling was limited to the compact formation of the nucleus ambiguus and the central subnucleus of the nucleus of the solitary tract. Most fluorescence-labeled neurons in the central subnucleus stained positively for NADPH (double labeled). In the compact formation, there were almost no double-labeled neurons; however, NADPH-stained terminals surrounded fluorescence-labeled motoneurons.

CONCLUSIONS

NO synthase is present in premotor neurons of the central subnucleus of the nucleus of the solitary tract that innervate esophageal motoneurons in the compact formation of the nucleus ambiguus. NADPH staining in both somata and terminals of esophageal premotor neurons suggests that NO is involved in neurotransmission in the central subnucleus and at the site of synaptic contact between esophageal premotor neurons and motoneurons in the compact formation of the nucleus ambiguus.

[Identification on the botanical origin of xueshangyizhihao produced in Shaanxi, Gansu, Sichuan Provinces and Ningxia Hui Autonomous Region]

The botanical origin of Xueshangyizhihao should be Aconitum brachypodum var. laxiflorum produced in Dongchuan, Huize and Xundian districts in Yunnan Province. Recently, this herb has been found coming from Shaanxi, Gansu, Sichuan Provinces and Ningxia Hui Autonomous Region. Botanical identification show that except the one from Sichuan being of the same origin as that from Yunnan, this herb consists essentially of the species of genus Aconitum, mainly A. flavum, A. pendulum, and others such as A. sungpanense, A. polyschistum and A. iudlowii.

The relationship of Piry virus to other vesiculoviruses: a re-evaluation based on the glycoprotein gene sequence

By sequencing the 3 half of the Piry virus genome, we show that Piry virus, like the other vesiculoviruses, contains the genes for nucleoprotein N, phosphoprotein P, matrix protein M, glycoprotein G and polymerase protein L, in that order. Our analysis of the Piry G protein sequence suggests that Piry and Chandipura are related to each other as closely as the Indiana and New Jersey vesicular stomatitis virus serotypes are to each other. A re-examination of amino acid sequences in the nucleocapsid protein shows that this relationship is also true of the more conserved central region of this protein and that the greatest divergence between Piry and Chandipura has occurred in two other regions of the nucleocapsid protein.

Brain stem localization of rodent esophageal premotor neurons revealed by transneuronal passage of pseudorabies virus

BACKGROUND/AIMS

Brain stem premotor neurons control swallowing through contacts with both afferent neurons and motoneurons. The location and connectivity of premotor neurons innervating the esophagus was determined using pseudorabies virus.

METHODS

In 30 rats, viral injections were made into either the cervical or subdiaphragmatic esophagus, cricothyroid muscle, or stomach. After a 48-62-hour survival, brain sections were processed immunocytochemically for the virus.

RESULTS

Neuronal labeling was limited to the compact formation of the nucleus ambiguus for survivals of 48-54 hours. At 57-62-hour survivals, virus-labeled second-order neurons (premotor neurons) were localized to the central subnucleus of nucleus of the solitary tract. Injections in the cricothyroid muscle and stomach resulted in distinct patterns of motoneuronal labeling in the nucleus ambiguus and dorsal motor nucleus and premotor neuronal labeling in the nucleus of the solitary tract.

CONCLUSIONS

Virus-labeled premotor neurons in the nucleus of the solitary tract occurred as a result of retrograde transport of the virus from the nucleus ambiguus because no viral antigen was present in the tractus solitarius. The esophagus is controlled by a central circuit whereby esophageal vagal afferents terminate on premotor neurons in the central subnucleus that in turn innervate esophageal motoneurons in the nucleus ambiguus.

Cystic fibrosis transmembrane conductance regulator protein expression in brain

The cystic fibrosis transmembrane conductance regulator protein (CFTR) has been identified in bovine brain clathrin-coated vesicles, rat brain and a human neuroblastoma cell line using affinity-purified polyclonal peptide antibodies against CFTR. Immunocytochemical staining of multiple dendrites and soma of neurons of the diencephalon, midbrain, pons and medulla oblongata, has also been demonstrated. Whole cell lysates and membranes derived from rat brain, neuroblastoma cells and bovine brain clathrin-coated vesicles express the mature 150-165 kDa and 130 kDa unglycosylated forms of CFTR. The localization of CFTR to brain regions controlling homeostasis and energy expenditure may relate to the pathogenesis of non-pulmonary manifestations of cystic fibrosis. CFTR expression in neurons and coated vesicles suggests a possible effect on neuropeptide vesicle trafficking by mutant CFTR.

Dendritic architecture of hypoglossal motoneurons projecting to extrinsic tongue musculature in the rat

The tracer, cholera toxin-horseradish peroxidase, was used to determine the dendritic architecture and organization of hypoglossal motoneurons in the rat. In 22 animals, the tracer was injected unilaterally into either the geniohyoid, genioglossus, hyoglossus, or styloglossus muscle. Within the hypoglossal nucleus, motoneurons innervating the extrinsic tongue muscles were functionally organized. Geniohyoid and genioglossus motoneurons were located within the ventrolateral and ventromedial subnuclei, respectively, while hyoglossus and styloglossus motoneurons were located within the dorsal subnucleus. Motoneurons located in all subnuclear divisions were found to have extensive dendrites that extended laterally into the adjacent reticular formation and medially to the ependyma. Less extensive extranuclear dendritic projections were found in the dorsal vagal complex and median raphe. Prominent rostrocaudal and mediolateral dendritic bundling was evident within the ventral subnuclei and dorsal subnucleus, respectively. Dendritic projections were also found extending inter- and intrasubnuclearly with a distinct pattern for each muscle. These data suggest that the varied and extensive dendritic arborizations of hypoglossal motoneurons provide the potential for a wide range of afferent contacts for, and interactions among, motoneurons that could contribute to the modulation of their activity. Specifically, the prominent dendritic bundling may provide an anatomic substrate whereby motoneurons innervating a specific muscle receive and integrate similar afferent input and are thus modulated as a functional unit. In contrast, the extensive intermingling of both inter- and intrasubnuclear dendrites within the hypoglossal nucleus may provide a mechanism for the coordination of different muscles, acting synergistically or antagonistically to produce a tongue movement.

22-km distributed temperature sensor using Brillouin gain in an optical fiber

We describe an experimental distributed temperature sensor that uses the temperature dependence of the Brillouin frequency shift. When a 22.2-km sensing length is used, we have observed a temperature resolution of 1 degrees C and have obtained a spatial resolution of 10 m.

Principal optical constants measurement of uniaxial crystal CdSe in the wavelength region between 380 and 950 nm

The principal optical constants n(o), k(o), n(e), and k(e) of the hexagonal crystal CdSe are determined in the wavelength region between 380 and 950 nm at room temperature. The minimum reflectivities and the corresponding Brewster angles of parallel polarized light are measured for ordinary and extraordinary rays in the wavelength region between 380 and 728 nm. At longer wavelengths (k(o) < 10(-3)) Brewsterangle measurements and transmission measurements were applied. A plot of the absorption coefficients alpha(o) and alpha(e) versus wavelength indicates deviations from a direct band-gap parabolic absorption dependence.

[Study and preparation of Vi-PHA reagent and its application for detection of Salmonella typhi carriers]

Purified S. typhi Vi antigen is sensitized with equal volume of tannic acid treated formalational sheep erythrocytes (SRBC) at a final concentration of 1 microgram/ml. The Vi-passive hemagglutination assay (Vi-PHA) diagnostic reagent is developed to detect Vi antibodies to S. typhi for the detection of chronic carriers after typhoid fever and the screening S. typhi healthy carriers from food-handlers, which is characterized with high sensitivity, strong specificity and good stability. This Vi-PHA reagent is able to detect 1.16 micrograms/ml of Vi antibodies and doesn't make any cross reaction with healthy sera. For the sera of other diseases, the cross rate is only 0.84%. Using this reagent, 19 positive sera (6.93%) are detected from 274 convalescent sera from typhoid fever, 14 convalescents of which are stool-culture S. typhi positive, that persists a positive rate of 73.68%; 3 positive sera are detected from 106 foodhandlers, one of which is stool-culture S. typhi positive. Therefore, the reagent is simple, convenient, rapid and easy to be applicated in basic unit.

[Effect of second somatonorm treatment in idiopathic growth hormone deficiency dwarfism]

Nine previously treated idiopathic growth hormone deficiency children were treated again with recombinant hGH for one year. The dosage and route of administration were the same as those in the previous treatment. The height velocity increased from 1.5 +/- 1.0 cm/year (mean +/- SD) to 9.2 +/- 1.2 cm/year. Compared with the height velocity (10.7 +/- 0.5 cm/a) in the first year treatment, it decreased in the second year (P less than 0.05). The results also showed that the effect was better with a dosage of 0.7 IU/kg/wk divided into 7 s.c. doses than with 0.5 IU/kg/wk divided into 3 i.m. doses. Eight of the 9 cases had low serum T4 after treatment, but no symptoms of hypothyroidism were seen. Anti-hGH antibody was observed in 2 cases, though it did not affect the height velocity. No other side effects were noticed during treatment.