Quantitative and qualitative yield in sweet maize hybrids.

Today, sweet corn is considered an important vegetable due to its high sugar content and low starch content. Cluster analysis and variance analysis showed that hybrids had variations in yield indices. GB, DE and GS hybrids had similar performance on indices. SE hybrid that has significant performance on zeaxanthin. Biplot showed that fructose, glucose, sucrose and potassium had stability value on hybrids. All the hybrids had the best performance on fructose, glucose, sucrose and potassium factors. Factor biplot positively correlated with yield indices, including calcium, iron, zinc, magnesium, α-Carotene, 9Z-ß-Carotene, phosphorus, and ß-carotene. On the other hand, there is a positive correlation with fructose, glucose, potassium, lutein, sucrose, ß-Cryptoxanthin, and zeaxanthin. So, to evaluate or increase lutein and zeaxanthin, the other parameters like sugar content (fructose, glucose, and sucrose) are important factors and have an effect together. Factor analysis and biplot showed that ME hybrid had a maximum performance on the first factor of yield indices. Also, the second factor of yield indices had a maxi-mum effect on NO hybrids. SE hybrids had maximum performance in zeaxanthin and GS hybrid had maximum performance in zinc, phosphorus, and iron. The dry matter had stability on DB hybrid.

Hydrocarbon decomposition in alumina membrane: an effective way to produce carbon nanotubes bundles.

Carbon nanotubes were synthesised within the pores of an alumina membrane. The membrane had 200 nm diameter pores and 60 microm thickness, and ethylene was used as carbon source. Membrane dissolution by HF results in a bundle of parallel open tubes, aligned without macroscopic defects. The external diameter of the tubes is uniform and there is no evidence of any amorphous carbon. Wall thickness control was obtained by varying the reaction time, length by the thickness of alumina membrane, and external tube diameter by the membrane pore size. Scanning (SEM) and transmission (TEM) electron microscopy, atomic force microscopy (AFM), X-ray diffraction, thermogravimetric analysis (TG) and surface area evaluation by nitrogen adsorption were used for the characterization of membrane and nanotubes.

Evaluation of assays for determination of passive transfer status in neonatal llamas and alpacas.

OBJECTIVE: To evaluate several practice-adapted assays for determination of passive transfer status in crias. ANIMALS: 24 llama and 9 alpaca crias. DESIGN: Prospective study. PROCEDURE: Serum IgG concentration was measured by use of a radial immunodiffusion assay when crias were 45 to 51 hours old. Results were compared with serum gamma-glutamyltransferase (GGT) activity, serum total protein, albumin, globulin, and total solids concentrations, and results of commercially available and traditional sodium sulfite turbidity (SST) tests. RESULTS: Mean (+/- SD) serum IgG concentration was 1,762 +/- 1,153 mg/dl. On the basis of a threshold value of 1,000 mg of IgG/dl at 48 hours of age, 5 of 33 (15.15%) crias had failure of passive transfer. Serum total solids, protein, and globulin concentrations were significantly associated with serum IgG concentration, whereas serum GGT activity and serum albumin concentration were not. Serum IgG concentrations were significantly different among crias with negative, 2+, and 3+ scores on the traditional SST test. Serum IgG concentrations were not significantly different between crias with negative and 100 mg/dl scores or 100 and 300 mg/dl scores on the commercially available SST test. However, all other comparisons between crias with different scores revealed significant differences. Sensitivity and specificity ranged between 0 and 1, depending on the test and endpoint selected. CONCLUSIONS AND CLINICAL RELEVANCE: The commercially available SST test and determination of serum total protein and globulin concentrations are suitable methods for assessing passive transfer status in llama and alpaca crias.

A note on the early history of renal transplantation: Emerich (Imre) Ullmann.

In January 1902 at the Vienna Medical Society Meeting, the surgeon Emerich Ullmann reported the first case of renal autotransplantation performed in the neck of a dog. In the same year, he presented the first xenotransplantation of the kidney (a goat with a dog's kidney). These publications immediately had a great impact on the medical word. After his failed attempt to transplant a pig's kidney into a young uraemic woman he stopped his research in this field in order to devote himself to other lines of surgical research. However, his idea survived him, because, nowadays, nearly 100 years later, pigs appear to be the most suitable donors for human renal xenotransplantation. Ullmann was born in Pécs, Hungary, on February 23, 1861. After a distinguished undergraduate career in 1878 his father (being also a medical doctor) sent him to study medicine at the world-famous Vienna Medical School. He graduated in 1884 and was immediately invited to the Surgical Department where Billroth worked. Next year, because of his interest in bacteriology he visited Pasteur in Paris and successfully volunteered to serve as a healthy subject to prove the effectiveness of Pasteur's antisera against rabies. Although Ullmann did not succeed in doing a human transplantation he gave birth to the era of the organ transplantation, stimulated vascular surgery and the development of transplantation immunology.

Astrocytic gap junction removal, connexin43 redistribution, and epitope masking at excitatory amino acid lesion sites in rat brain.

We previously reported that kainic acid (KA) lesion sites in rat brain exhibit an absence of astrocytic gap junctions at 1 week post-lesion. Loss of immunocytochemical reactivity with a sequence-specific antibody against the astrocytic gap junctional protein connexin43 (Cx43) suggested epitope masking since persistence of Cx43 was observed on Western blots. Here, we determined the fate of Cx43 at various times after thalamic KA and striatal NMDA lesions. In normal tissue and at 6 hr post-KA lesion, Cx43 immunoreactivity predominated at typical astrocytic gap junctions. Immunolabelled junctions were still seen at 3 days, with epitope masking already present, and were virtually absent by 6 days post-lesion. Gap junction remodeling was indicated by the appearance of intracellular immunostained annular profiles and uncharacteristically extensive gap junctions between symmetrically immunolabelled membranes and between labelled astrocytic and unlabelled oligodendrocytic membranes. Labelled multivesicular clusters emerged at 2 days, were numerous at 3 days and constituted the sole Cx43 sequestration site by post-lesion day 6. Ultrastructural disruption and gap junction disassembly progressed more slowly in NMDA-injected tissue where immunoreactivity persisted, albeit at markedly decreasing levels until the final survival time examined (16 days). Intense Cx43 immunolabelling was seen in filopodia of putative reactive astrocytes at the lesion periphery at 6-8 days and was associated at 16 days with an increased number of gap junctions primarily between fine astrocytic processes. These results demonstrate that massive neuronal loss alone or in conjunction with direct actions of excitotoxins on astrocytes precipitates an astrocytic reaction accompanied initially by removal of their gap junctions followed by redistribution of Cx43, and suggest that the astrocytic syncytium may undergo reorganization in a manner leading to isolation of the lesion site.

Spin relaxation studies of pyrene by 13C nuclear magnetic resonance spectroscopy.

The effect of the repetition and contact times on the intensity of the magic-angle spinning (MAS) spectra of pyrene has been studied. Pyrene, like a great number of fused polyaromatic compounds, has a very large 13C longitudinal relaxation time (T1Z). When using the cross-polarization (CP) MAS technique, the optimum repetition time is 800 s. The simulation of the central line of the pyrene CP-MAS spectra allowed us to determine the chemical shift of each carbon in the solid state. As the T1Z (13C of the total spectrum) of pyrene was observed to be 1780 s, attempts have been made to relax it by the addition of chromium(III) acetylacetonate or by supporting it on a carrier of gamma-Al2O3: the mixing of chromium(III) acetylacetonate to pyrene by solid mixing, or solution mixing followed by evaporation of the solvent, has no effect on its relaxation time; the Haldor Topsøe TK551 catalyst, a gamma-alumina supported Ni-Mo-P catalyst, has been found to be a very efficient spin relaxation agent for the products adsorbed on it. For example, at 25 degrees C, the 10 wt.-% pyrene-TK551 catalyst is 3 x 10(4) times more relaxed than pure pyrene.

In vitro degradation of thymopoietin32-35 in human, dog and rat plasma.

TP4 (Arg-Lys-Asp-Val) is a synthetic immunomodulatory tetrapeptide of Chemical Works of Gedeon Richter Ltd. The aim of this study was to give comparative data on the in vitro degradation of 14C-TP4 in plasma of different species at two TP4 concentrations to allow suitable extrapolation of preclinical data to human system. The results show that the degradation was very fast in each plasma and varied by the species and concentrations studied. In rat, dog and human plasma for initial concentration of 80 micrograms/ml and 800 micrograms/ml the apparent half-life values proved to be 1.4, 1.8, 2.7 and 3.9, 6.3, 13.6 minutes, respectively. The most susceptible breakdown point was the peptide bond between Arg and Lys. The correlation between TP4 degradation and arginine formation was demonstrated by a straight line with a correlation coefficient of 0.99565 and a slope close to -1.

Intracranial transplantation and survival of tuberomammillary histaminergic neurons.

Investigations were undertaken to determine whether fetal histaminergic neurons in the tuberomammillary nucleus of the posterior hypothalamus survive intracranial transplantation to adult hosts. Two methods of transplantation were utilized. Grafts were placed either into the delayed cavity of a fimbria-fornix lesion or directly into the hippocampus using stereotaxic techniques. The tissue was taken from rat fetuses at embryonic days 16-17 and grafted into adult rats of either the Sprague-Dawley or the Fischer 344 strain. Routine histology and immunohistochemistry were used to evaluate the grafts. All transplants to Sprague-Dawley rats showed signs of rejection, while no signs of rejection were seen in any of the Fischer 344 rats. Transplants placed directly into the delayed fimbria-fornix cavity did not grow as well or contain as many surviving neurons as the intraparenchymal grafts. The largest number of surviving histamine-positive neurons was obtained with grafts of posterolateral blocks of hypothalamus from fetal day 17 placed directly into the CA1 region of the rostral hippocampal formation of Fischer 344 hosts. Histamine-immunoreactive cell bodies with neuritic outgrowth were found in all Fischer 344 rats that received hypothalamic grafts. Cell bodies exhibited histamine immunoreactivity evenly throughout the cytoplasm and had morphological characteristics resembling histaminergic neurons in situ. Axonal outgrowth extended throughout the grafted hypothalamic tissue, and was sometimes seen in the host hippocampal tissue as well. It is concluded that fetal histaminergic neurons survive transplantation to the adult hippocampal formation, and that this allograft procedure can supplement current strategies to investigate the function of histaminergic tuberomamillary neurons in the central nervous system.

HPLC-purified bovine satietin suppresses food intake and weight without causing conditioned taste aversion.

Satietin (SAT) is a putative satiety agent found in a variety of species including man and the rat. In the present study, satietin was extracted from bovine plasma (b-SAT) and further high-pressure liquid chromatography (HPLC)-purified. Rats were given chronic third ventricle cannulas and patency was verified. In experiment 1, rats were divided into three groups and ICV infused with artificial cerebrospinal fluid (a-CSF) or b-SAT: group 1, a-CSF (n = 11); group 2, 20 micrograms/rat, b-SAT (n = 11); and group 3, 40 micrograms/rat, b-SAT (n = 9). Infusions were repeated thrice three days apart. Compared to a-CSF, the high b-SAT dose suppressed food intake for 24-h after each successive infusion. The low dose significantly decreased food intake only after the first infusion. Water intake was suppressed only after the first injection of the high dose. Body weight was decreased after the first and second infusions of both doses and following the third infusion of the high dose. In experiment 2, rats were trained to drink fluid for 1 h/day while food was ad lib. On day 1, both groups received no infusions and were given tap water. On day 2, the groups were ICV infused with a-CSF, but group 1 (n = 12) was given banana-flavored fluid (BFF) and group 2 (n = 12) almond-flavored fluid (AFF). On day 3, group 1 was again a-CSF-infused but given AFF, whereas group 2 received 40 micrograms/rat b-SAT and was given BFF.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypercholesterolemia promotes endothelial dysfunction in vitamin E- and selenium-deficient rats.

Abnormal regulation of local vascular tone occurs early in human and experimental atherosclerosis. Impaired endothelium-dependent vascular relaxations mediated by endothelium-derived relaxing factor are an important contributor to these abnormalities. Endothelium-derived relaxing factor is nitric oxide released as such or attached to a carrier molecule. Oxidized lipoproteins impede endothelium-derived relaxing factor-mediated responses in vitro. We designed in vivo experiments to determine whether hypercholesterolemia with and without deficiency of two endogenous lipid antioxidants, vitamin E and selenium, would result in endothelial dysfunction. Vitamin E and selenium deficiencies were induced in a group of hypertension-prone Dahl salt-sensitive rats fed a diet high in cholesterol (4%) but low in NaCl (0.5%) for 18 weeks. Two other groups of Dahl salt-sensitive rats received diets sufficient in vitamin E and selenium but containing either high or normal cholesterol levels (control group). Serum cholesterol levels increased approximately 10-fold in the two groups of rats fed high-cholesterol diets. Systolic blood pressure was 143 +/- 3 mm Hg in high-cholesterol/vitamin E- and selenium-sufficient rats and 142 +/- 5 mm Hg in high-cholesterol/vitamin E- and selenium-deficient rats (P = NS). Mild intimal thickening and occasional mononuclear cell infiltration were observed in both of these groups. Serum vitamin E levels were decreased, whereas serum thiobarbituric acid-reactive substances and exhaled pentane (two indicators of endogenous lipid oxidation) were significantly increased in high-cholesterol/vitamin E- and selenium-deficient rats compared with high-cholesterol/vitamin E- and selenium-sufficient rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Depletion of connexin43-immunoreactivity in astrocytes after kainic acid-induced lesions in rat brain.

Recent studies have established that the gap junction protein connexin43 is a major structural component of gap junctions between astrocytes in rat brain. Here, we investigated by immunohistochemical methods the effect of kainic acid-induced neuronal degeneration on connexin43 expression by astrocytes. Stereotaxic injections of kainic acid into the thalamus were found to cause a near total depletion of connexin43-immunoreactivity at the lesion site. Areas depleted of connexin43 corresponded to those exhibiting substantial neuronal loss and intense gliosis. These results implicate a neuronal contribution to the regulation of connexin43 expression by astrocytes and, hence, to local control of the potassium spatial buffering capacity afforded by astrocyte gap junctions.

Distinct adenosine deaminase-containing inputs to the substantia nigra from the striatum and tuberomammillary nucleus.

Immunohistochemical, neuroanatomical and lesion methods were used to investigate the projections of adenosine deaminase immunoreactive (ADA-IR) neurons in the striatum (caudate/putamen) and hypothalamus to the substantia nigra (SN). Striatal ADA-IR neurons were distributed within two zones; anteriorly in the medial and ventromedial extreme of the head and body of the striatum, and posteriorly in the tail of the striatum. The posterior hypothalamus contained ADA-positive neurons which were confined to the tuberomammillary nucleus (TM). The SN was devoid of ADA-positive neurons, but contained two distinct types of ADA-IR fiber terminations. One type was confined to bands located at the ventrolateral and dorsomedial borders of the pars reticulata and consisted of fine puncta. The other type was distributed throughout the SN and consisted of long, beaded fibers. Injections of the retrograde tracer Fluoro-gold (FG) into the SN gave rise to FG-labelling of significant numbers of ADA-IR neurons in both the striatum and TM. Medial SN injections preferentially labelled ADA-IR neurons in the anterior striatum and lateral SN injections labelled posterior ADA-IR striatal neurons. Kainic acid lesions of the anterior medial striatum selectively abolished the punctate ADA-IR band in the medial SN and left the long, ADA-IR nigral fibers in an apparently hypertrophied state. Despite depletion of ADA-IR neurons in the striatum by kainic acid, ADA activity increased significantly at striatal lesion sites. The results suggest that the SN receives two topographically segregated fine terminal fields from striatal ADA-IR neurons, and a substantial innervation from ADA-IR neurons in the TM as well. These findings add to the heterogeneous chemical composition of nigral afferents and are discussed in the context of adenosine neuromodulatory mechanisms in the striatonigral system.

The organization and hypothalamic projections of the tuberomammillary nucleus in the rat: an immunohistochemical study of adenosine deaminase-positive neurons and fibers.

The intense immunohistochemical reaction for the enzyme adenosine deaminase displayed by neurons in the tuberomammillary nucleus in the rat was used to study the distribution and morphology of cells comprising this nucleus, their fiber fields within the posterior hypothalamus and their projection pathways from the hypothalamus. Neurons immunoreactive for adenosine deaminase were found along ventricular and basal aspects of the hypothalamus from the level of the dorsomedial nucleus to the caudal pole of the mammillary body. Approximately 4500 neurons were seen on each side of the brain. Positive neurons showed a complex distribution, largely avoiding nuclear boundaries within the posterior basal hypothalamus and mammillary body. This distribution is mapped in detail and a nomenclature based on topography is introduced so that different regions of the cell distribution may be discussed more easily. Reactive neurons showed a Golgi-like staining which allowed careful study of their morphology. In general, neurons were large, with major axes of from 22 to 30 micron, and bipolar in shape. A second, smaller cell type, 14-16 micron in diameter was also seen and, although often less intensely stained, it was considered a constituent of tuberomammillary nucleus of the hypothalamus as well. Stained dendritic arbours extended considerable distances from the parent cell bodies and branched regularly. Dendrites showed very sparse spines and had an apparently scalloped surface. Features suggestive of varicose segments of dendrites were also noted. The long, smooth dendrites of positive neurons were often seen to aggregate into bundles which avoided nuclear boundaries and tended to collect adjacent to basal and ventricular surfaces of the posterior hypothalamus. Varicose fibers immunoreactive for adenosine deaminase formed a dense network within the hypothalamus. These fibers were considered to derive from the positive neurons in the tuberomammillary nucleus and were similar to adenosine deaminase-immunoreactive fibers seen throughout much of the rest of the brain. The density of this type of positive fiber was, however, much greater within the hypothalamus. The region of the posterior basal hypothalamus also contained relatively sparse populations of adenosine deaminase-positive fibers, apparently distinct from this network. These consisted of a field of fine fibers in the median division of the medial mammillary nucleus and a few large varicosities in the dorsolateral part of the median eminence.(ABSTRACT TRUNCATED AT 400 WORDS)

Ontogenesis of adenosine deaminase activity in rat brain.

The activity of adenosine deaminase (ADA) was determined in whole brain of rats at the embryonic age of 15 days through to adulthood and in nine brain regions in rats 1 day old through to adulthood. In 1-day-old rats, the highest activity was seen in olfactory bulbs (550 +/- 15 nmol/mg protein/30 min) and this was 4.5-fold higher than that in the pons, which was the lowest. In adult animals, olfactory bulb still contained the greatest activity, which was about eightfold higher than hippocampus, which had the lowest. Except for hypothalamus, where ADA activity increased nearly twofold in rats between the ages of 1 and 50 days, significant decreases of as much as fivefold were found in whole brain, superior colliculus, cortex, hippocampus, cerebellum, olfactory bulbs, and olfactory nucleus. In contrast, ADA activity in pons and subcortex remained relatively constant throughout the developmental period. The Km values for ADA in whole brain at 18 days gestation (48 +/- 5 microM) were not significantly different from that observed in adult rats (38 +/- 7 microM), whereas the Vmax values decreased significantly from 339 +/- 9 to 108 +/- 8 nmol/mg protein/30 min. Taken together, the developmental patterns observed in the various brain regions appear not to correspond to any one particular process such as periods of rapid cell proliferation, cell death, synaptogenesis, or myelination. Nor do they correspond to known developmental profiles of transmitters, their receptors, or their metabolic enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuronal colocalization of adenosine deaminase, monoamine oxidase, galanin and 5-hydroxytryptophan uptake in the tuberomammillary nucleus of the rat.

Neurons of the tuberomammillary nucleus (TM) in the rat have previously been shown to contain the enzymes adenosine deaminase (ADA), histidine decarboxylase (HDC) and glutamate decarboxylase (GAD). Some neurons coextensive with this cell group also exhibit immunoreactivity for the neuropeptide galanin, express monoamine oxidase activity (MAO), or display the ability to accumulate and decarboxylate 5-hydroxytryptophan (5-HTP). Histochemical and immunohistochemical techniques were used to determine the extent to which these neurochemical properties are colocalized in neurons immunoreactive for adenosine deaminase. Galanin was found to coexist with ADA in about 45% of the neurons in the TM. In addition, a large number of cells immunoreactive for galanin alone were observed in the posterior hypothalamus outside the confines of TM. Neurons displaying MAO activity formed a subpopulation of those immunoreactive for ADA; all neurons containing MAO also contained ADA whereas only 60% of the ADA-immunoreactive cells were reactive for MAO. Approximately 20% of ADA-immunoreactive neurons represented nearly all cells having 5-HTP uptake capability. However, a very few cells in TM showing 5-HTP uptake capability appeared to be devoid of ADA immunoreactivity. These results demonstrate that although neurons of TM are homogeneous with respect to a number of possible neurotransmitters markers and associated enzymes, these neurons are heterogeneous with respect to their expression of galanin, MAO and 5-HTP uptake. In certain respects the segregation of histochemical properties within TM correlates with previous histochemical work by others, and suggests the possibility of functional diversity of TM.

Adenosine deaminase-containing hypothalamic neurons accumulate 5-hydroxytryptophan: a dual-colour immunofluorescence procedure using a new fluorescence marker.

Neurons of the posterior hypothalamic magnocellular nucleus (PHMN) in the rat are immunoreactive for adenosine deaminase (ADA) and cells coextensive with this nucleus show immunoreactivity for serotonin after pretreatment with 5-hydroxytryptophan (5-HTP). The degree to which ADA coexists in cells having 5-HTP uptake capability was analyzed by a new double immunohistofluorescence procedure employing diethylaminocoumarin (DAMC). It was determined that 5-HTP accumulating cells of the PHMN represent a subpopulation of those immunoreactive for ADA. These results add further to the neurochemical characterization of this globally projecting hypothalamic cell group and point out the utility of DAMC as a new immunohistofluorescence marker.

On the innervation of trigeminal mesencephalic primary afferent neurons by adenosine deaminase-containing projections from the hypothalamus in the rat.

The localization and sources of adenosine deaminase-containing structures in the mesencephalic nucleus of the trigeminal nerve of the rat was studied using indirect immunofluorescence or immunoperoxidase immunohistochemical staining techniques for adenosine deaminase in combination with retrograde fluorescent tracing or lesion methods. The majority of large mesencephalic neurons were engulfed by a dense adenosine deaminase-immunoreactive plexus. Immunostaining was often punctate surrounding neuronal profiles or sometimes had the appearance of varicose fibers coursing over the neuronal surface. Occasionally, immunostained axons were found travelling towards and contacting mesencephalic neurons. Mesencephalic neuronal somas surrounded by immunofluorescence staining for adenosine deaminase were simultaneously labelled with fast blue after injections of this dye into the temporalis or masseter muscles of mastication. Injections of fast blue into the mesencephalic nucleus resulted in fast blue labelling of adenosine deaminase-immunoreactive neurons in the tuberal, caudal and postmammillary caudal magnocellular nuclei of the hypothalamus. Ablation of these hypothalamic nuclei caused a near total depletion of adenosine deaminase-immunostained fibers in the mesencephalic nucleus including those associated with mesencephalic neurons. It is concluded that adenosine deaminase-containing neurons in the posterior hypothalamus innervate mesencephalic primary sensory neurons, which are known to convey proprioceptive input to trigeminal motor nuclei controlling jaw muscles. The possibility is considered that the hypothalamus, via a direct action on these sensory neurons, may exert automatic control over jaw movements related to aggressive attack, defensive or feeding behavior. In addition, it appears that mesencephalic neurons may provide an ideal model system for electrophysiological investigations of the neurotransmitter(s) utilized by adenosine deaminase-containing hypothalamic projections.

Autotomy in rats after peripheral nerve section: lack of effect of topical nerve or neonatal capsaicin treatment.

The influence of capsaicin on autotomy was studied in adult rats in which the sciatic and saphenous nerves were sectioned. Capsaicin was administered subcutaneously to neonatal rats or applied topically to the sciatic and saphenous nerves in adult animals. Quantification of neurogenic plasma extravasation in skin areas subserved by these nerves and of the number of small type B neurones in lumbar sensory ganglia were used to confirm the effectiveness of capsaicin-induced lesions of unmyelinated sensory nerves. Neonatal capsaicin treatment significantly reduced neuronal numbers in ganglia and, compared to control responses, plasma extravasation was nearly abolished after both neonatal and peripheral nerve treatment with capsaicin. Despite these deficits in sensory neurones function, no differences in any parameters of autotomy were observed between animals receiving both capsaicin treatment and nerve section and those given nerve section alone. Animals in both control and experimental groups exhibited high autotomy scores. These results suggest that capsaicin-sensitive primary sensory neurones do not have a significant role in precipitating autotomy characterized by high incidence and severity.

Coexistence of adenosine deaminase, histidine decarboxylase, and glutamate decarboxylase in hypothalamic neurons of the rat.

Neurons immunoreactive for the enzyme adenosine deaminase (ADA) in the posterior basal hypothalamus of the rat have a distribution pattern similar to those immunoreactive for histidine decarboxylase (HDC) and are particularly numerous in the tuberal (TM), caudal (CM) and postmammillary caudal (PCM) hypothalamic magnocellular nuclei which harbor neurons containing glutamic acid decarboxylase (GAD). The extent to which these enzymes coexist within neurons of these hypothalamic regions was examined using either serial sections or simultaneous immunostaining for ADA and HDC or GAD in the same section. Analysis of serial sections revealed neuronal coexistence of ADA with HDC or GAD in both TM and CM. In addition some neurons in CM, the only area examined for triple coexistence, were found to contain all three enzymes. In sections processed for ADA simultaneously with HDC or GAD, nearly all ADA-immunoreactive neurons in TM, CM, and PCM as well as those scattered between these nuclei were found to contain HDC, and nearly all contained GAD. Exceptions to this, however, were small cells located lateral to the posterior arcuate nucleus, which appeared to contain ADA but not HDC, and large neurons located at the anterior extreme of TM, which appeared to contain ADA but not GAD. The relatively few ADA- compared with GAD-containing neural systems in brain, together with the presence of ADA in GAD-containing hypothalamic magnocellular neurons, which appear to have widespread projections throughout the brain, indicate that ADA may be a convenient immunohistochemical marker for anatomical investigations of these projections.(ABSTRACT TRUNCATED AT 250 WORDS)