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At least 37 records · Page 2Linked to original sources
PubMed1988

Enkephalin-like immunoreactive principal ganglion cells and nerve fibres in the inferior mesenteric ganglion of the cat.

The occurrence and distribution of methionine-enkephalin (ME), leucine-enkephalin (LE) and methionine-enkephalin-Arg6-Gly7-Leu8 (MERGL)-like (LI) immunoreactive material in the inferior mesenteric ganglion (IMG) of the cat were studied by immunohistochemical techniques using the peroxidase-antiperoxidase method. Numerous ME-Li, LE-Li and MERGL-Li immunoreactive fibres with the same distribution pattern were observed. They were varicose and often surrounded closely neighbouring unlabelled ganglion cell bodies. Sometimes they ran in strands between ganglion cells. ME-Li immunoreactive material was detected in a number of cell bodies, the diameter of which was similar to that of unlabelled principal ganglion cell bodies, and which were probably Enk-Li-containing principal ganglion cells. These immunoreactive cells were often surrounded by ME-Li immunoreactive fibres. No LE-Li or MERGL-Li immunoreactive ganglion cell bodies were observed. The presence of ME-Li immunoreactive principal ganglion cells raises the possibility that the Enk-Li immunoreactive fibres present in the IMG may have a prevertebral ganglionic source. The possibility that the Enk-Li material present in nerve fibres might be derived from preproenkephalin-A was suggested by the occurrence of MERGL-Li immunoreactivity.

Animals↗
PubMed1975

Detachment of structurally intact nerve endings from chromatolytic neurones of rat superior cervical ganglion during the depression of synaptic transmission induced by post-ganglionic axotomy.

1. Electrophysiological studies showed that injury of post-ganglionic nerve fibres leads to severe and prolonged depression of synaptic transmission through the rat superior cervical ganglion, beginning within 24 h. This is in line with the results of previous studies in other species and upon other neurones. 2. electron microscopy after post-ganglionic axotomy revealed nerve endings of presynaptic type with all the specialized membrane-related features of a synaptic zone, but which were not apposed to any post-synaptic nervous element. These umusual profiles were interpreted as detached presynaptic nerve endings. In normal and control ganglia, such profiles formed at most 0-5% of all vesicle-containing profiles of presynaptic type; in ganglia with all major post-ganglionic branches cut the proportion rose to approximately 7%, between 3 and 7 d post-operatively. Over this period, the mean incidence of chromatolytic neurones was 74-6%. 3. Concomitantly, the incidence of synapses within the ganglion fell by about 75%, reaching its lowest levels between 3 and 7 d post-operatively. There was strikingly little evidence of persistence of post-synaptic membrane specializations ('membrane thickenings') following detachment of synapses. 4. At longer survival intervals the incidence of synapses gradually increased, and that of detached nerve endings gradually decreased; recovery was well advanced by 42 d. 5. The fall in the incidence of synapses was closely paralleled by a fall in the incidence of desmosome-like attachments in the ganglion; the incidence of such attachments was found to be correlated to a significant degree with that of synapses. 6. It is concluded that most or all of the synapses upon sympathetic neurones become physically dissociated during the chromatolytic reaction of these neurones to axotomy. The failure to persist of ultrastructurally specialized post-synaptic sites, and the loss of desmosomes (particularly marked for those involving purely post-ganglionic nervous elements) suggest that the post-ganglionic neurone is losing all its specializations for attachment. 7. Some evidence suggests that the satellite cells may effect the final separation between pre- and post-synaptic structures.

Action Potentials↗
PubMed1986

Outgoing synapses of small granule-containing cells in the rat superior cervical ganglion after post-ganglionic axotomy.

Small granule-containing cells are intrinsic and interneurone-like in the rat superior cervical ganglion, being innervated by preganglionic axons and giving outgoing synapses of asymmetrical type to the principal neurones. A quantitative ultrastructural investigation has been made of the effect on these outgoing synapses of axotomy of the major post-ganglionic nerve trunks 18.5 h-390 days previously. Cutting, or cutting and ligating, the internal and external carotid nerves 2-3 mm from the ganglion in rats aged 1.5-5.5 months resulted in a statistically significant mean loss of up to 85% of the asymmetrical synapses given by small granule-containing cells in the injured ganglion. The reduction of synapses was maximal 5-9 days post-operatively, and thereafter the incidence of synapses showed significant signs of progressive recovery. The time course and magnitude of the change in incidence of these synapses resembled those found earlier (Matthews & Nelson, 1975) for the loss of preganglionic synapses to principal neurones in the same ganglia, and after an identical post-ganglionic lesion. Control experiments showed that there was no loss of outgoing synapses from the small granule-containing cells as a result of surgical stress or of simple ageing. Older rats (5.5 and 13 months) showed a small but significant increase in the incidence of these synapses. Unilateral post-ganglionic axotomy produced the same reaction in the injured ganglia as did bilateral lesions. Uninjured ganglia contralateral to unilateral axotomies, however, also showed some deficit of outgoing synapses from small granule-containing cells, but this was slight, amounting to 9.9% over-all in comparison to normal values in young rats, and this difference did not reach statistical significance. Cutting the cervical sympathetic trunk to produce preganglionic denervation 2 days before surgical removal of ganglia for analysis did not alter the incidence of outgoing synapses of the small granule-containing cells, either in ganglia post-ganglionically axotomized 5-128 days earlier or in contralateral ganglia, indicating that at no stage was any significant proportion of these synapses given to preganglionic axons. These findings suggest that most of the outgoing synapses from the intra-ganglionic small granule-containing cells are directed to principal neurones whose axons leave with the injured branches, the internal and external carotid nerves.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1979

Route of infection, systemic host resistance, and integrity of ganglionic axons influence acute and latent herpes simplex virus infection of the superior cervical ganglion.

The character of acute and latent herpes simplex virus (HSV) infection of the superior cervical ganglion (SCG) in mice depended on the route by which the virus reached the ganglion, the level of systemic host resistance, and the integrity of postganglionic nerves. Prevention of ganglionic infection by postganglionic neurectomy carried out before intraocular (i.o.) virus challenge established the importance of the neural route in the development of SCG infection. However, hematogenous virus dissemination also led to SCG infection although with reduced frequency compared to that with i.o. inoculation. Enhanced host systemic antiviral resistance had two divergent effects on ganglionic infection depending on the dose and timing of virus inoculation. Thus, both acute and latent ganglionic infections were concomitantly reduced when resistant C57B1/6 mice were challenged with low doses of virus or when less resistant BALB/c mice were actively immunized 1 week before virus challenge. On the other hand, when resistant mice were challenged with high doses of virus or when either active or passive (antibody) immunization was delayed long enough to assure viral access to the ganglion, intraganglionic viral replication during the acute phase of infection was reduced, but the prevalence of subsequent latent infection was either unaffected or actually enhanced. Postganglionic neurectomy, performed after virus had reached the ganglion, altered the course of SCG infection in a direction opposite that of immunization, augmenting the acute phase of viral replication while reducing latency. In athymic nude mice and mice immunosuppressed with cyclophosphamide, intraganglionic viral replication was prolonged. These results emphasize that host factors both extrinsic and intrinsic to the SCG modify the course of ganglionic infection.

Acute Disease↗
PubMed1981

Cell survival in chick embryo ciliary ganglion is reduced by chronic ganglionic blockade.

Changes in the activities of enzymes involved in the synthesis or degradation of transmitters has been used as an index of maturation in autonomic neurons. In some cases, a reduction in enzyme activity during normal development may reflect decreased cell survival rather than, or in addition to, changes in the rate of development. Similarly, changes in enzyme activity following experimental manipulation during development may also reflect cell loss. In the ciliary ganglion, biochemical indexes of development are altered after denervation, and after treatment with a ganglionic blocker, chlorisondamine. Surgical removal of afferents to the ciliary ganglion in the early chick embryo results in a virtually complete loss of ganglion cells. Chiappinelli et al. have reported that choline acetyltransferase (ChAT) is reduced in chick iris and ciliary ganglion after chronic treatment with chlorisondamine (on days 5, 8, 10 and 13 of incubation). This suggests that the development of transmitter enzymes may be regulated via interaction at the presynaptic site. Since they also report that chlorisondamine treatment reduced ganglionic dry weight, which could reflect a loss of cells, it may be that the same synaptic interaction governs cell survival as well as enzyme maturation. The present study provides evidence that treatment with chlorisondamine does, in fact, reduce cell survival in the ciliary ganglion.

Afferent Pathways↗
PubMed1985

Development of the rat superior cervical ganglion: ganglion cell maturation.

The development of superior cervical ganglion cells has been studied in the fetal rat. Sympathetic cells appear first in thoracic sites and, one day later, in cervical sites; localized proliferation among these cells gives rise to the superior cervical and stellate ganglia. The maturation of superior cervical ganglion cells was examined by staining these neurons with horseradish peroxidase in fetal preparations maintained in vitro. This method showed that cells begin to extend processes at widely different times, without regard to a given cell's position in the ganglion. Postganglionic axons appear as early as day 12 of gestation (E12), when only a small number of ganglion cells have emerged from the mitotic cycle. The axon generally originates from a point on the ganglion cell body that is oriented toward the route of subsequent axon extension. As the postganglionic axons grow, they do not branch within the superior cervical ganglion and branch only to a slight extent, if at all, within developing peripheral nerves. Axonal growth is rapid, and fibers reach relatively remote sympathetic targets as early as E15. Dendrites first appear on E14 and are elaborated by ganglion cells that have already extended their axons. By the end of gestation, the number of primary dendrites found on some cells already falls within the range found in maturity.

Animals↗
PubMed1987

Ganglion cell density in albino and pigmented rabbit retinas labeled with a ganglion cell-specific monoclonal antibody.

Retinas from two rabbits, one normally pigmented and one albino, were labeled with monoclonal antibody AB5, which has been shown to be a specific marker for ganglion cells. This method obviates criteria for distinguishing among ganglion cells, displaced amacrine cells, and glia. Labeled cells were counted within small fields at some 2000 regularly spaced points on each retina. These counts were transformed to maps of ganglion cell density. In general, the density map for the pigmented retina was similar to those obtained by earlier studies with non-specific stains, thereby confirming the basic validity of most previous studies and demonstrating the applicability of AB5 labeling to work of this type. The ganglion cell density map of the albino retina was abnormal, showing a clear deficit of ganglion cells in the nasal portion of the visual streak. This result not only indicates that the albino anomaly has retinal effects, but also suggests a major impact on ganglion cells whose projections (in normal animals) are contralateral.

Albinism↗
PubMed1988

Localization of L-glutamate decarboxylase immunoreactivity in the major pelvic ganglion and in the coeliac-superior mesenteric ganglion complex of the rat.

The localization of L-glutamate decarboxylase (GAD), the GABA-synthesizing enzyme, was studied in the rat major pelvic ganglion and in the coeliac-superior mesenteric ganglion complex by indirect immunofluorescence technique with a specific antiserum raised in rabbits. GAD immunoreactivity was demonstrated in small cells of these ganglia. The GAD-immunoreactive small cells were 10-20 microns in diameter and formed clusters or occurred as solitary cells. The principal neurons were non-reactive but they were surrounded by immunoreactive processes. Studies on colocalization of GAD with tyrosine hydroxylase (TH), the rate-limiting enzyme of the catecholamine synthesis, in the major pelvic ganglion and in the coeliac-superior mesenteric ganglion complex indicated that all GAD-immunoreactive small cells were also labelled with TH. In the major pelvic ganglion all TH-immunoreactive SIF cells were also immunoreactive for GAD. However, in the coeliac-superior mesenteric ganglion complex there occurred TH-immunoreactive small cells which showed no immunoreactivity to GAD. It is suggested that the small GAD-immunoreactive cells represent small intensely fluorescent (SIF) cells.

Animals↗
PubMed1973

The effect of N6-2'-O dibutyryl 3',5' cyclic adenosine monophosphate, imidazole and aminophylline on ganglionic transmission in the superior cervical ganglion of the cat.

1. Dibutyryl cyclic AMP, injected towards the superior cervical ganglion of the cat, produced no consistent responses.2. Imidazole, injected towards the ganglion, regularly produced facilitation, both during intermittent and continuous preganglionic stimulation. This effect was dose-dependent and lasted 2-10 minutes.3. Aminophylline, injected towards the ganglion, regularly produced depression of ganglionic transmission, both during intermittent and continuous preganglionic stimulation. This effect was also dose-dependent and lasted 1-4 minutes. Papaverine produced the same type of response as aminophylline.4. Imidazole potentiated the ganglionic response to 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP), while aminophylline depressed it.5. The results of the present experiments are consistent with the view that cyclic AMP may have a mediating role in the process of ganglionic transmission.

Aminophylline↗
PubMed1986

Incoming synapses and size of small granule-containing cells in a rat sympathetic ganglion after post-ganglionic axotomy.

A quantitative ultrastructural study has been made of the reaction of the incoming synapses of small granule-containing cells after axotomy of the major post-ganglionic branches of the superior cervical ganglion of the young adult rat. These cells are intrinsic and interneurone-like in this ganglion, receiving a preganglionic input and giving outgoing synapses to principal post-ganglionic neurones. Unlike their outgoing synapses, which are lost after post-ganglionic axotomy (Case & Matthews, 1986), the incoming synapses of the small granule-containing cells in axotomized ganglia increased in incidence post-operatively. The increase first became clearly evident 5-7 days post-operatively and was greater, being both more sustained and progressive, after bilateral than after unilateral axotomy. After bilateral axotomy the incidence of incoming synapses rose to more than four times that of normal ganglia and was still elevated at 128 days post-operatively, but was within normal limits at 390 days. After a unilateral lesion, increases of similar extent and time course to those in the axotomized ganglia were seen in the incoming synapses of small granule-containing cells in the uninjured contralateral ganglia. The incoming synapses of the small granule-containing cells are multifocal, i.e. show several points or active foci of synaptic specialization. The increase in synapses expressed itself both through an increased incidence of these synaptic active foci per nerve terminal and through an increase in the number of presynaptic nerve terminal profiles associated with the cells. Control observations indicated that the increase in synapses was not due to surgical stress, nor was it attributable solely to post-operative ageing. The nerve terminals which were presynaptic to the small granule-containing cells post-operatively were all of preganglionic origin: no incoming synapses or presynaptic nerve terminals remained at 2 days after a preganglionic denervation of axotomized or contralateral ganglia, at whatever stage this was performed throughout the range of survival intervals. There was some evidence that the synapses had increased by sprouting, including terminal sprouting, of the preganglionic nerve fibres. In the shorter term there was an increase in the proportion of small nerve terminal profiles. In the longer term the mean size of the terminal profiles increased, and very large terminals of unusual form were seen. After post-ganglionic axotomy, and in particular after a bilateral lesion, the small granule-containing cells became hypertrophied.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1996

Effects of peripheral nerve ligation on expression of mu-opioid receptor in sensory ganglion neurons: an immunohistochemical study in dorsal root and nodose ganglion neurons of the rat.

The present study was attempted to examine if mu-opioid receptor (MOR) might be transported by axonal flow peripherally through peripheral axons of somatic sensory ganglion neurons. After unilateral ligation of the sciatic nerve or the vagus nerve distal to the dorsal root ganglion (DRG) or nodose ganglion (NG), MOR-like immunoreactivity (MOR-LI) of neuronal cell bodies in the DRG of the fourth and fifth lumbar nerves, NG, ambiguus nucleus (Amb) and dorsal motor nucleus of the vagus nerve (DMV) on the side of the ligation was apparently reduced within 1 week after the nerve ligation. However, within 24 h after the nerve ligation, a transient enhancement of MOR-LI was observed in cell bodies of DRG neurons, sciatic nerve stump proximal to the ligature, and cell bodies of NG neurons on the side of the ligation; such a transient enhancement of MOR-LI was not detected in the Amb and DMV. The results suggest that MOR undergoes centrifugal axonal flow in peripheral axons of somatic and visceral sensory ganglion neurons, and that MOR synthesis in sensory ganglion neurons is vulnerable to damage of the peripheral axons.

Analgesics, Opioid↗
PubMedDate not supplied

Effect of the bispyridinium oximes HGG12 and HGG42 and ganglion blocking agents on synaptic transmission and NAD(P)H-fluorescence in the superior cervical ganglion of the rat after Soman poisoning in vitro.

HGG12 and HGG42 are effective therapeutic agents in experimental organophosphate poisoning even after "aging" of the phosphonylated cholinesterase (Hauser, Kirsch, Weger, 1981). In this study we investigated their action in the isolated superior cervical ganglion of the rat (SCGR) after cholinesterase inhibition by Soman (.4 microM). As these two compounds have ganglion blocking properties (Kirsch, Weger, 1981), the action of hexamethonium bromide (C6) and atropine was also investigated and compared to theirs. The typical effects of Soman in the SCGR are a block of ganglionic transmission within 10 sec in a test train of stimuli of 6 Hz, 30 sec, and an increase of the NAD(P)H-fluorescence response up to 3 times the control value. Addition of HGG12 or HGG42 in a concentration of 30-60 microM restores transmission and decreases the metabolic response to almost normal values while obidoxime (60 microM) has no effect at all. C6 (117 microM) and to a lesser degree atropine (30-60 microM) also improve ganglionic transmission and the metabolic response in cholinesterase poisoning. The pattern of amplitudes of APs in a test train of stimuli however is only restored by the HGG compounds and a comparison of equipotent concentrations (50% inhibition of AP in unpoisoned ganglia) shows that HGG12 has the best effects in Soman poisoned SCGR. The superiority of HGG12 can be explained by an inhibitory action of HGG12 on both nicotinic and muscarinic ganglionic receptors.

Action Potentials↗
PubMedDate not supplied

Alpha ganglion cells in mammalian retinae: common properties, species differences, and some comments on other ganglion cells.

A specific morphological class of ganglion cell, the alpha cell, was first defined in cat retina. Alpha cells have since been found in a wide range of mammalian retinae, including several orders of placental and marsupial mammals. Characteristically, they have the largest somata and a large dendritic field with a typical branching pattern. They occur as inner and outer stratifying subpopulations, presumably corresponding to ON-center and OFF-center receptive fields. In all species, alpha cells account for less than 10% of the ganglion cells, their somata are regularly spaced, and their dendritic fields evenly and economically cover the retina in a mosaic-like fashion. The morphology of alpha cells and many features, both of single cells and of the population, are conserved across species with different habitats and life-styles. This suggests that alpha cells are a consistent obligatory ganglion cell type in every mammalian retina and probably subserve some fundamental task(s) in visual performance. Some general rules about the construction principles of ganglion cell classes are inferred from the alpha cells, stressing the importance of population parameters for the definition of a class. The principle, that a functionally and morphologically homogeneous population should have a regular arrangement and a complete and even coverage of the retina to perform its part in image processing at each retinal location, is especially evident across species and across ganglion cell types.

Animals↗
PubMed2005

Relationship between dorsal ganglion cysts of the wrist and intraosseous ganglion cysts of the carpal bones.

Soft tissue ganglion cysts are the most common benign tumours of the wrist; their pathogenesis remains controversial. We prospectively screened the radiographic appearance of the wrists of 51 patients presenting to a single surgeon with dorsal wrist ganglions during a one-year period. Postero-anterior and lateral radiographs were systematically performed looking for possible associated intraosseous ganglion cysts. There were 51 dorsal soft tissue ganglion cysts in 51 patients. We detected 29 associated intraosseous ganglia in 24 patients (47%): 16 ganglia in the lunate bone (55%), 5 in the capitate bone, 7 in the scaphoid and 1 in the trapezoid. Mean size of the intraosseous ganglia was 3 mm (range, 2 to 5 mm). This high prevalence of intraosseous ganglia in association with soft tissue ganglia has to our knowledge never been reported previously. A common aetiology for these two types of ganglion cysts may explain this high association rate.

Bone Cysts↗
PubMed1980

Effects of alpha adrenergic blockade, combined nicotinic and muscarinic ganglion blockade and spinal anesthesia upon norepinephrine depression of ganglion transmission in the dog.

The effects of blocking agents upon the depression of transmission of the combined stellate and caudal cervical ganglia produced by the close intra-arterial injection of norepinephrine have been studied in the anesthetized dog. The results of this study showed that combined nicotinic and muscarinic ganglion blockade with chlorisondamine and atropine did not decrease the amount of norepinephrine-produced depression of transmission. This depression of ganglion transmission was converted to a stimulation by the close intra-arterial administration of the alpha adrenergic blocking drug phentolamine. Blockade of all preganglionic impulses by the production of total spinal anesthesia blocked the depression of ganglion transmission produced by norepinephrine and prevented the conversion of this depression to a stimulation by phentolamine. Phentolamine, when administered by close intra-arterial injection, produced a dose-dependent, prolonged stimulation of transmission through the ganglia. The results of this study infer that the norepinephrine depression of ganglion transmission is at some site other than the usual muscarinic and nicotinic ganglion pathways and that spinal pathways are involved.

Adrenergic alpha-Antagonists↗
PubMed1982

Evidence for a blood-ganglion barrier in the superior cervical ganglion of the rat.

The permeability of the blood vessels in the superior cervical ganglion of the rat was tested by intravenous injection of horseradish peroxidase (HRP). By light microscopy, peroxidase activity was found in three locations: in the capsule of the ganglion, in the lumina of the blood vessels, and within macrophages. Electron microscopy revealed that virtually all ganglionic blood vessels contained HRP 5 minutes following its administration. The intensity of peroxidase activity declined over the period of 15 minutes. The enzyme was localized on the luminal surface of the endothelial cells, attaching to the glycocalyx. Endothelial microvilli, projecting into the vessel lumen, were also covered with peroxidase. Micropinocytotic vesicles on the luminal surface of the endothelium contained reaction product. Some of these vesicles were free within the cytoplasm of the endothelium but none was observed on the abluminal surface. Peroxidase activity was not detected in the extracellular space even after 15 minutes. The majority of blood vessels in the superior cervical ganglion possess a continuous endothelium with tight junctions; features associated with the blood-brain barrier of the central nervous system and peripheral nerves. It is proposed that these vessels perform a barrier function between the capillary circulation and the superior cervical ganglion.

Animals↗
PubMed2005

Postnatal-related changes in the size and total number of neurons in the caudal mesenteric ganglion of dogs: total number of neurons can be predicted from body weight and ganglion volume.

Aging is mostly characterized by a progressive decline of neuronal function that involves both the central and the peripheral nervous system. The aging process is accompanied by changes in either the number or the size of neurons. However, these data are controversial and not very well known in the sympathetic ganglia of large mammals. Hence, the present investigation aimed to study the dog's caudal mesenteric ganglion (CMG) in three different periods of postnatal development, searching for qualitative and quantitative alterations. The CMG is responsible for the large intestine, internal anal sphincter, and partially the urogenital system innervations. Nine dead male dogs from the Veterinary Hospital of the College of Veterinary Medicine at University of São Paulo were divided into three well-defined age groups (1-2 months old, 1-2 years old, and 5-10 years old). The stereological study was pursued using the physical disector method combined to the Cavalieri principle. The postnatal development was accompanied by an increase in the nonneuronal tissue amount and in ganglion volume. Additionally, the total number of neurons also increased during aging (from 70,140 to 1,204,516), although the neuronal density showed an opposite trend (from 29,911 to 11,500 mm(-3)). Due to the interrelation between either body weight or ganglion volume and aging in the dogs investigated in this study, it was possible to predict the total number of neurons in CMG using both body weight and ganglion volume in an attempt to verify whether or not size and total number of neurons are both allometrically and aging ruled, i.e., if either the animal's body weight and ganglion volume or aging influence these parameters. The prediction of the total number of neurons was very close to the initially estimated values.

Aging↗
PubMed1983

Effects of histamine agonists and antagonists (H1 and H2) on ganglionic transmission and on accumulation of cyclic nucleotides (cAMP and cGMP) in rat superior cervical ganglion in vitro.

Histamine and 4-methylhistamine inhibited ganglionic transmission in the rat superior cervical ganglion in vitro via H2-histaminergic receptors. Under blockade of H2-receptors, 4-methylhistamine sometimes showed slight facilitation of ganglionic transmission, when repetitive stimuli were applied. The H1-receptor agonist, 2-pyridylethylamine, was ineffective. Histamine and 4-methylhistamine increased both cyclic AMP (cAMP) and cyclic GMP (cGMP) levels in concentrations depressing ganglionic transmission, whereas 2-pyridylethylamine increased only cAMP concentrations in the isolated ganglia. Histamine-induced accumulation of cyclic nucleotides was only partially prevented by either histamine--H1- and H2-receptor antagonists, but abolished by their combination. It is concluded that changes in intraganglionic cyclic nucleotides induced by histaminergic receptor agonists did not apparently correlate with their effect on ganglionic transmission in vitro.

Action Potentials↗