PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Ganglia, Sympathetic”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1976

Developmental variations of tyrosine hydroxylase and acetylcholinesterase in embryonic and post-hatching chicken sympathetic ganglia.

The developmental variations of tyrosine hydroxylase (TH) and of acetylcholinesterase (AChE) were studied in embryonic and post-hatching chicken sympathetic ganglia. Different levels of TH activity were found in two different flocks of White Leghorn chicken, which are probably dependent on genetic differences. These enzymatic differences, however, do not become apparent before hatching and may indicate a combined effect of genetic variation and functional demands. During the period of incubation, TH activity is characterized by a pronounced and steady increase from the twelfth day of incubation up to day 2 after hatching. This corresponds to a period of intense maturation of the sympathetic neuron. In the period following hatching, the 'fourth day fall phenomenon' previously described by us for DOPA decarboxylase (DDC), dopamine-beta-hydroxylase (DBH), and monoamine oxidase (MAO) is not seen in the TH curve. Instead, TH activity tends to remain constant between days 2 and 14 after hatching (ah). Both ganglionic protein and weight remain constant in this period, indicating a phase of general pause in protein synthesis. AChE activity increases steadily from the eighth until the twenty-first day of incubation. A sudden and significant drop in AChE activity was found at day 2 ah followed by a period of rapid increase at day 3 ah and a levelling of activity up to day 30 ah. Comparing the present variations to those observed in our previous studies on DBH, a temporal relationship between TH and DBH activity is observed during the phases of synaptogenesis and maturation but not during the phase of intense functional activity. Our results strongly suggest that before hatching in chick embryo sympathetic ganglia, the cholinergic presynaptic terminals play a role in regulating the development of the adrenergic neurons. In the period following hatching, however, the DBH and TH levels in cell bodies seem to be principally regulated by the functional activity. This results in depletion of DBH, but not TH, through liberation along with the neurotransmitter at the periphery. Depletion of DBH at the terminals may result in increased transport and thereby depletion in the cell body. This mechanism is probably responsible for the difference in the profiles of activity of DBH and TH in the cell bodies observed in the first week after hatching.

Acetylcholinesterase↗
PubMed1979

Evidence for autonomic paraneurons in sympathetic ganglia of a shrew (Tupaia glis).

The morphological relationships between blood vessels and the small monoamine-storing cells have been studied in the superior sympathetic ganglia of Tupaia. Substantial clusters of these cells were found to be associated anatomically with vascular loops or glomeruli. Blood from these glomeruli enters the capillary bed that supplies principal ganglionic neurons. Thus the vascular path for catecholamine transportation is rather clearly defined in Tupaia, providing new morphological evidence for the existence of a portal system for conveying catecholamine from clusters of paraneurons to principal ganglionic neurons. On the basis of vesicle criteria, two populations of small, granule-containing cell were distinguished, and both were encountered in the same cluster. On the basis of fluorescence microscopy, the relatively small number (14.3%) of solitary SIF cells may be true interneurons because, although there has been no electron microscopic identification of efferent synapses, their processes are much longer than those of the paraneurons.

Animals↗
PubMed1977

Selective induction of tyrosine hydroxylase and dopamine beta-hydroxylase by nerve growth factor: comparison between adrenal medulla and sympathetic ganglia of adult and newborn rats.

Administration of NGF to newborn and adult rats elicits a selective increase in TH and DBH both in sympathetic ganglia and adrenal medulla. This effect does not depend on intact preganglionic cholinergic fibers. The augmented enzyme activity results from enhanced enzyme synthesis since it can be abolished by cycloheximide and NGF has been shown to enhance the incorporation of [3H]leucine into DBH molecules. The responsiveness of the adrenal medulla to NGF is also supported by light and electron microscopic autoradiograms which show that intravenously injected 125I-NGF is accumulated with high selectivity in adrenal chromaffin as compared to adjacent adrenal cortical cells. In spite of the many similarities between the response of the adrenergic neurons and adrenal chromaffin cells to NGF, there are also two distinct differences. (a) In newborn rats the ratio between the TH increase effected by a single and 10 subsequent daily injections of NGF is 1:2 in the adrenal medulla and 1:7 in the superior cervical ganglia. (b) If adrenal medullae are transferred to organ culture after intravenous injection of NGF, maximal TH response is initiated 60-90 min after NGF administration. In superior cervical ganglia only a half-maximal response is initiated at that time. After a stationary phase a second increase starts after about 6 h to reach the maximum after 12 h. The biphasic time course of the initiation of TH induction by NGF in sympathetic ganglia is in agreement with the time course of 125I-NGF accumulation after intravenous injection27 reflecting the moiety of NGF reaching the cell bodies of the adrenergic neurons directly by the blood stream (initial accumulation) and by retrograde axonal transport (second phase).

Adrenal Medulla↗
PubMed1976

A histochemical investigation on mucopolysaccharides in the dog sympathetic ganglia.

A histochemical study in the dog Superior Cervical ganglion and in the Cervicothoracic or Stellate ganglion is reported. The mucopolysaccharide composition of these ganglia are studied by means of five histochemical techniques. The different histochemical composition between the neurons of these ganglia is investigated. In the sections stained with the PAS technique some neurons appeared more intensely stained than the others. With Thionin or Toluidine blue some neurones appeared more metachromatic than others. A peculiar distribution of the Nissl bodies, related with metachromasia, is reported. In sections stained with the Colloidal Iron method yellow neurons like those presented in the dorsal root ganglia were not found in the sympathetic ganglia. This fact suggests that the yellow neurons might be a different type of neuron. The possibility that the staining variations associated to the distribution of the Nissl bodies perhaps correspond to different functional states of the same type of neurons is also suggested.

Animals↗
PubMed1976

Binding of alpha-bungarotoxin to chick sympathetic ganglia: properties of the receptor and its rate of appearance during developement.

Studies were carried out on the binding of [125I]alpha-bungarotoxin (alphaBT) to membrane fragments of chick sympathetic ganglia. Specific binding of toxin was saturable with a KD of 1.1 nM. The rates of association and dissociation of the toxin from ganglionic membranes were 4.3 X 10(4) M-1 sec-1 and 4.6 X 10(-5) sec-1 (t 1/2 = 4.2 h). respectively. Binding was inhibited (by up to 95%) by low concentrations of nicotinic, but not by a muscarinic cholinergic ligand. The properties of the ganglionic binding site for alphaBT were consistent with its being a nicotinic acetylcholine receptor. The development of toxin receptors in chick ganglia was also studied. From days 7 to 11 in ovo, few receptors were present; from days 12 to 20 in ovo, there was a 10-fold increase in receptor number per ganglion; from hatching to maturity, the receptor number per ganglion slowly increased and reached a maximum of 14 fmoles. The ontogeny of receptors for alphaBT in sympathetic ganglia appears to correlate with the cytological maturation and innervation of the principal neurons.

Age Factors↗
PubMed1976

Barbiturates block calcium uptake by stimulated and potassium-depolarized rat sympathetic ganglia.

The effects of two barbiturates on calcium uptake by sympathetic ganglia have been examined. Sodium pentobarbital (0.4-0.75 mM) and sodium thiopental (0.3 mM) block the preganglionic stimulation-induced uptake of 45Ca by rat superior cervical ganglia but not action potential conduction in the presynaptic axons. The ganglionic-blocking agent, tetraethylammonium, does not inhibit stimulation-induced Ca uptake and does not prevent the blocking effect of thiopental. This effect is therefore probably presynaptic. Postassium-rich media also stimulate Ca uptake by the ganglia, and this effect is markedly inhibited by pentobarbital. Since the K stimulation effect is also observed in deafferented ganglia but not in guanethidine-denervated ganglia, this effect is probably associated primarily with postsynaptic elements. In sum, the data suggest that the barbiturates inhibit Ca permeability changes in both pre- and postsynaptic neurons.

Animals↗
PubMed1976

Facilitation and depression of synaptic transmission in amphibian sympathetic ganglia.

There have been few reports concerning facilitation and depression in sympathetic ganglia9,17,40. In the present investigation, pairs of excitatory postsynaptic potentials (EPSPs) were recorded intracellularly from bullfrog paravertebral sympathetic ganglia for an analysis of the site and mechanism responsible for the phenomena of facilitation and depression of ganglionic transmission. The ratio of the amplitude of the second of a depression of ganglionic transmission. The ratio of the amplitude of the second of a pair of EPSPs divided by the first was compared to the time interval between each pair of EPSPs divided by the first was compared to the time interval between each pulse. These ratios demonstrated two phases: an earlier phase of facilitation (20-500 msec pulse intervals) and a later phase of depression (500 msec-10 sec). Additional parameters-rate of rise of synaptic potentials (dV/dt), synaptic currents (EPSCs), and synaptic conductances (Gtr)-were determined and all confirmed the results obtained with EPSPs. Furthermore, the degree of facilitation or depression could be modulated by altering the extracellular concentration of calcium. On the other hand, comparison of the amplitude of pairs of presynaptic terminal spikes did not show any variability over similar stimulus intervals, nor were the amplitudes of miniature EPSPs significantly different before or after an evoked EPSP. Therefore, the processes of facilitation and depression of ganglionic transmission occur as a result of normal nerve terminal activity. The processes are occurring simultaneously, such that one or the other may predominate depending upon the interval between pulses, as well as the relative concentration of extracellular calcium.

Animals↗
PubMed1979

Hyperpolarizing 'alpha 2'-adrenoceptors in rat sympathetic ganglia.

1 Receptors mediating catecholamine-induced hyperpolarization of isolated superior cervical sympathetic ganglia of the rat have been characterized by means of an extracellular recording method.2 (-)-Noradrenaline (EC(50), 1.7 +/- 0.6 muM) produced an immediate low-amplitude (< 400 muV) hyperpolarization. The hyperpolarization was increased on removal of external Ca(2+) or on reduction of external K(+) from 6 to 2 mM. Hyperpolarization was unaffected by changing the temperature from 25 degrees to 37 degrees C.3 Hyperpolarization was also produced by the following agonists (potencies relative to (-)-noradrenaline): (-)-noradrenaline 1; (+/-)-isoprenaline 0.41; (-)-phenylephrine 0.40; (+)-noradrenaline 0.13; 2-amino-6,7-dihydroxy tetrahydronaphthalene (ADTN) 0.25; dopamine 0.1; methoxamine 0.012; amidephrine 0.0015.4 Responses were antagonized by phentolamine (1 muM) but not by (+/-)-propranolol (1 muM), haloperidol (10 muM) or alpha-flupenthixol (1 muM). This suggested that hyperpolarization was mediated solely through alpha-receptor stimulation not through stimulation of beta-receptors or dopamine-receptors.5 Dose-ratio shifts produced by phentolamine varied with different agonists. The shift increased in inverse proportion to the ability of the agonists to inhibit [(3)H]-(-)-noradrenaline uptake, suggesting that uptake of agonists limited the dose-ratio shift. Cocaine and nortriptyline reduced catecholamine-induced hyperpolarization in concentrations (10 muM and 1 muM respectively) necessary to inhibit [(3)H]-(-)-noradrenaline uptake.6 Clonidine (0.01 to 1 muM), oxymetazoline (0.01 to 1 muM) and ergometrine (0.1 to 10 muM) produced a persistent, low-amplitude hyperpolarization, as though they were partial agonists. Responses to the agonists were blocked by yohimbine (1 muM) but not be prazosin (1 muM).7 It is concluded that the adrenergic cell bodies in the ganglion were hyperpolarized through activation of the same type of alpha-receptor (;alpha(2)-receptors') as those present at adrenergic nerve terminals.

Animals↗
PubMed1975

Amphibian sympathetic ganglia in tissue culture.

1. A culture medium has been developed for amphibian sympathetic nervous tissue but it is suggested that the ionic values should be adjusted to correspond to the concentrations of salts in the plasma of particular species. 2. The morphology, monoamine fluorescence, growth and differentiation of sympathetic ganglia of the frog, Limnodynastes dumerili, have been studied in culture. 3. Two types of neuron could be distinguished largely according to size, namely small, 18 X 20 mum and large, 38 X 42 mum. The possibility that these represent one type at different stages in development or represent functionally distinct neurons is discussed. 4. The sympathetic neurons are extremely sensitive to nerve growth factor (NGF) which caused an increase in the size of the cell bodies, the number of nerve fibres regenerating, the rate of axonal growth and synthesis of catecholamines. 5. Various other cell types appearing in the cultures have been described, including chromaffin, satellite, Schwann, multipolar and epithelial cells as well as fibroblasts, melanocytes and macrophages. The epithelial cells show slow contractions and changes in shape.

Acetylcholinesterase↗
PubMed1977

Nerve growth factor prevents vinblastine destructive effects on sympathetic ganglia in newborn mice.

Vinblastine injections in newborn mice produce severe atrophy of sympathetic ganglia; after a 7-day treatment the ganglia are 80% reduced in volume. Histological examinations show that this effect is due to a marked decrease in the neuronal cell population. The most precocious ultra-structural alterations are localized in the nuclear compartment, followed by axonal swelling and microtubule disappearance. Simultaneous injections of nerve growth factor entirely prevent the noxious effects of the vinca alkaloid, and result in partial appearance of the growth effects of nerve growth factor. Such protective action is not due to inhibition of vinblastine uptake which is the same in control mice and in mice pretreated with nerve growth factor. It is suggested that nerve growth factor prevents the vinca alkaloid action by favoring the assembly or organization, or both, of microtubules, which, from in vitro studies, have been proved to be inaccessible to vinblastine.

Animals↗
PubMed1978

[Mechanisms of inhibition of synaptic transmission in the sympathetic ganglia of rats with alloxan diabetes].

In experiments on the isolated superior cervical sympathetic ganglia of rats with alloxan diabetes rhythmic stimulation of preganglionic nerves was effected; summation presynaptic spikes and EPSPs of ganglionic neurons were registered. In rats with moderately severe alloxan diabetes progressive depression of rhythmic ganglion potentials was connected with suppression of the mediator emission to the impulse due to rapid exhaustion of its operational fraction. Rats with severe diabetes displayed also postsynaptic suppression of the ganglionic neurons. Dynamic characteristics of the transmitter turnover assessed on the basis of consideration of the successive patterns of posttetanic potentiation showed insignificant changes in the mediator output and a significant (by 38%) suppression of the mediator reserve per sec in comparison with control.

Action Potentials↗
PubMed1977

Electron probe x-ray microanalysis of small granulated cells in rat sympathetic ganglia after sequential aldehyde and dichromate treatment.

Rat adrenal medulla and celiac-mesenteric sympathetic ganglia were fixed by a glutaraldehyde/formaldehyde-potassium dichromate-osmium treatment sequence and plastic-embedded. Fine sections were examined by electron probe x-ray microanalysis. Comparable peaks for chromium (Kalpha = 5.4 keV) were obtained from cytoplasmic fields containing membrane-bounded inclusion granules in both adrenomedullary noradrenaline cells and a type (type II) of sympathetic small granulated cell whose inclusion granules closely resemble those of the adrenomedullary noradrenaline cell. Chromium was not detected in granules within adrenomedullary adrenaline cells nor in two other sympathetic small granualted cell types. In no material was chromium detected in agranular cytoplasmic or nuclear fields. Since chromium binds to the Schiff monobase formed by glutaraldehyde and noradrenaline during fixation, we infer that noradrenaline is present in the granules of the type II sympathetic small granulated cell, as well as in adrenomedullary noradrenaline cells.

Adrenal Medulla↗
PubMed1978

Attraction of nerve fiber outgrowth from sympathetic ganglia to heart auricles in tissue culture.

Sympathetic chain ganglia of 3-day-old rats were cultured in Rose chambers for 5 days. Each chamber contained either two ganglia or a ganglion and a piece of heart atrium. Visual examination failed to show an increased density or length of nerve fibers growing towards the other explant. However, actual measurements showed that the length of nerve fiber outgrowth towards the atrium explant was about 10% longer than the mean outgrowth to all directions, the difference being statistically significant (P less than 0.0001). In ganglion-ganglion pair cultures the nerve fiber outgrowth towards the other ganglion tended to be shorter than that to other directions. It is tentatively concluded that atrium explants exert a growth-promoting influence on sympathetic nerve fibers in cultures, possibly due to diffusion of a growth-promoting substance from the atrium explant.

Animals↗
PubMed1975

The influence of nerve growth factor, potassium depolarization and dibutyryl (cyclic) adenosine 3',5'-monophosphate on explant cultures of chick embryo sympathetic ganglia.

Optimal nerve growth factor (NGF) and potassium concentrations for the culture of explants of single chick embryo sympathetic ganglia in Leighton tubes are described. NGF increases ganglionic monoamine oxidase (MAO; E.C.1.4.3.4) activity in a dose dependent fashion with maximum effects at a concentration of about 8 U/ml NGF. Peak activity compares closely with values seen in chick ganglia in vivo. Potassium-induced depolarization (45 mM K-+) also increases MAO activity; but the extent of the increase depends upon (NGF concentration, for there is little or no increase at high NGF concentrations. Dibutyryl adenosine 3',5'-cyclic monophosphoric acid (db cyclic AMP) can mimic the potassium-induced increase in MAO.

Animals↗
PubMed1978

Quantitative studies of sympathetic ganglia and spinal cord intermedio-lateral gray columns in familial dysautonomia.

In adult patients with familial dysautonomia the mean volume of superior cervical sympathetic ganglia is reduced to 34% of the normal of 222 mm3. Packing density of neurons is reduced to 37% of normal. The mean total number of ganglionic neurons is 120,000 as compared to 1,060,000 in controls. The mean totals of preganglionic neurons in the first three thoracic cord segments are 13,600 in patients and 25,150 in controls. Deficits in sympathetic neurons account for many of the clinical, pharmacological and biochemical manifestations of familial dysautonomia.

Adolescent↗
PubMed1977

Evidence for dopamine-storing interneurons and paraneurons in rhesus monkey sympathetic ganglia.

In order to study and quantify the small, intensely fluorescent (SIF) cells and to examine their synaptology, the superior cervical sympathetic ganglia of rhesus monkeys were examined by a sequential glyoxylic acid (GA) monoamine fluorescence and electron microscopic technique. Correlated data concerning the sensitivity of the ganglia to dopamine were gathered by measuring the rise in cyclic AMP levels following incubation in vitro with exogenous dopamine. Cyclic AMP levels after incubation for 12 min with 50 micron dopamine showed marked increases, averaging 288% of control values. This indicates that these ganglia contain a dopamine receptor-adenylate cyclase complex. The number of SIF cells per mg of tissue was about half that found in the cow and rabbit, and only 1% of the number observed in the rat. Morphological data support the view that, in this species, there are almost equal numbers of type I (hypothesized interneuron) and type II (paraneuron) SIF cells. Presumptive SIF cell efferent synapses were observed by electron microscopy, the postsynaptic elements being dendritic spines or very fine nerve processes.

Animals↗