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PubMed1999

A quantitative analysis of cells in the ganglion cell layer of the chick retina.

This study investigated the organization of cells in the ganglion cell layer (GCL) using Nissl staining, retrograde cell degeneration with axotomy of the optic nerve, and retrograde cell labeling by injections of horseradish peroxidase (HRP) into the optic nerve of chicks (posthatching day 1 and 8, P-1 and P-8). The total number of cells in the GCL was 6.1 x 10(6) (P-1) and 4.9 x 10(6) (P-8), and the cell density was 14,300 cells/mm2 (P-1) and 10,400 cells/ mm2 (P-8) on average. Two high-density areas, the central area (CA) and the dorsal area (DA), were observed in the central and dorsal retinas in both P-1 (22,000 cells/mm2 in CA, 19,000 cells/mm2 in DA) and P-8 chicks (19,000 cells/mm2 in CA, 12,800 cells/mm2 in DA). The cell densities in the temporal periphery (TP) and the nasal (NP) peripheral retinas were 7,800 cells/mm2 and 12,500 cells/mm2, respectively, in P-1 and 5,000 cells/ mm2 and 8,000 cells/mm2, respectively, in P-8 chicks. The cell density in the temporal periphery was 35% (P-8) lower than in the nasal periphery in both P-1 and P-8 chicks. Thirty percent (1.9 x 10(6) cells in P-1) of the total cells in the GCL were resistant to axotomy of the optic nerve. The distribution of the axotomy-resistant cells showed two high-density areas in the central and dorsal retinas, corresponding to the CA (5,800 cells/mm2) and the DA (3,200 cells/mm2). These cells also exhibited a center-peripheral increase (2,200 cells/mm2 in the TP) in P-1 chicks, but the high-density area was not found in the dorsal retina of P-8 chicks. From these data and the HRP study, the number of presumptive ganglion cells in P-8 chicks was estimated to be 4 x 10(6) (8,600 cells/mm2 on average), and the density in each area was 13,500 (CA), 10,200 (DA), and 4,300 (TP) cells/mm2. The peripheral/ center ratios of the density of ganglion cells were significantly different along the nasotemporal and dorsoventral axes. The density of ganglion cells decreased more rapidly toward the temporal periphery (TP/CA ratio: 0.47 in P-1 and 0.32 in P-8) than toward the nasal periphery (NP/CA ratio: 0.67 in P-1 and 0.52 in P-8). In contrast, there was no significant difference in the peripheral/center ratios between the dorsal retina (DP/CA ratio: 0.6 in P-1 and 0.56 in P-8) and ventral retina (VP/CA ratio: 0.58 in P-1 and 0.51 in P-8). A small peak in the density of the presumptive ganglion cells was detected in the dorsal retina of both P-1 chicks (10,800 cells/mm2) and P-8 chicks (10,200 cells/mm2). The HRP-labeled cells were small in the CA (M +/- SD: 35.7 +/- 9.1 microm2) and DA (40.0 +/- 11.3 microm2), and their sizes increased toward the periphery (63.4 +/- 29.7 microm2 in the TP) accompanied by a decrease in the cell density. However, the axotomy-resistant cells did not significantly increase in size toward the peripheral retina (12.2 +/- 2.2 microm2 in the CA, 15.2 +/- 3.2 microm2 in the DA, 15.1 +/- 3.8 microm2 in the TP). The characteristic distribution of ganglion cells could be related to visual behavior based upon the specialization of avian visual fields.

Animals↗

PubMed1988

An electrophysiological study of ganglion blockade by paraquat and diquat.

1. The bipyridilium herbicides, particularly paraquat, have chemical and toxicological features in common with the bi-quaternary ammonium ganglion blockers. 2. Paraquat and diquat were tested for ganglion blocking activity. Rabbit cervical ganglia were superfused with both agents and subsequently with hexamethonium to confirm susceptibility to ganglion blockade. 3. No evidence for ganglion blockade was found at either supra maximal or sub maximal stimulation, and none following repetitive stimulation. 4. The similarities and differences between the bipyridyl herbicides and bi-quaternary ganglion blockers can be explained on the basis of their structures. 5. It is concluded that neither paraquat nor diquat have significant ganglion blocking activity.

Animals↗

PubMedDate not supplied

Addition of lateral ganglionic eminence to rat mesencephalic grafts affects fiber outgrowth but does not enhance function.

Addition of embryonic striatal tissue, usually as a combination of the lateral and medial ganglionic eminences, to intrastriatal mesencephalic grafts has previously been reported to enhance recovery of drug-induced rotational behavior in the host and to modify axonal fiber outgrowth from the grafted dopaminergic neurons. This study investigated the effects of adding (cografting) either lateral or medial ganglionic eminence tissue to embryonic mesencephalic grafts implanted intrastriatally, in rats with unilateral 6-hydroxydopamine lesions. The cografts did not exhibit increased survival or cell size of dopaminergic neurons when compared to transplants of mesencephalic tissue alone. Neither did recipients of cografts exhibit any enhancement of graft-induced recovery of function, when tested for drug-induced rotational behavior or forelimb function in the staircase test. However, cografts containing lateral ganglionic eminence displayed patches of dense tyrosine hydroxylase-immunoreactive fibers within the graft tissue. These patches largely coincided with patches in adjacent stained sections, which were rich in immunostaining for the striatal-specific marker dopamine- and cyclic AMP-regulated phosphoprotein-32 (DARPP-32). Such patches were not present in rats receiving cografts containing medial ganglionic eminence or mesencephalic tissue alone. Thus, it seems that the grafted dopaminergic neurons preferentially grow into the areas of the transplants containing lateral ganglionic eminence tissue. In summary, the results suggest that embryonic lateral ganglionic eminence exerts trophic effects on the outgrowth of dopaminergic axons, but does not enhance the behavioral effects of grafted dopaminergic neurons.

Animals↗

PubMed1990

Contractions of the squid stellate ganglion.

Optical recording methods were used to characterize the intrinsic movements of squid stellate ganglia. Ganglionic contractions were rhythmic and occurred at a mean frequency of 8 min-1. Contractions were eliminated when Na+ in the external saline were replaced by Tris, but were only slowed when Na+ was replaced by sucrose. This suggests that Na+ plays some role in generating the contractions, but the complete abolition produced by Tris-containing saline may be due to a secondary pharmacological action of this ion. The Na+ channel blocker, tetrodotoxin, had no effect on contractions. Contractions were eliminated by removal of external Ca2+, by treatment with the inorganic Ca2+ channel blockers Mn2+ and Cd2+, or by treatment with the organic dihydropyridine Ca2+ channel blockers nitrendipine and nimodipine. Thus, extracellular Ca2+ plays an important role in generating the contractions. Because dihydropyridines eliminate contractions, but not synaptic transmission, they offer a means of studying transmission at the giant synapse of the stellate ganglion without having to contend with ganglionic movement. Electron microscopy of stellate ganglia revealed the presence of two types of cell that contained the organized arrays of cytoskeletal elements usually associated with contractile cells. One type was a pericyte that surrounded blood vessels within the stellate ganglion. The second type was distributed throughout the ganglion and resembled a smooth muscle cell. Either of these cell types might generate ganglionic contractions.

Animals↗

PubMed1994

A special type of ganglion cells in the submucous plexus of mouse small intestine.

The perikarya of sensory neurons have been reported frequently from electrophysiological studies of the plexus submucosus of many mammalian digestive tracts, but the fine structural characteristics of those cells or ganglia have rarely been demonstrated. Therefore, we conducted an electron microscopic study in search of possible sensory perikarya in the plexus of the mouse small intestine. Many ganglion cells scattered over the plexus submucosus possessed a few areas of fine granules frequently adjacent to dense bodies in their perikaryonal cytoplasm, as revealed first by Wilson et al. [23], who were unable to explain the significance, of this finding. On the other hand, one type of ganglion with a special three-dimensional structure was observed in the same plexus. This ganglion was composed of one central perikaryon, one innermost cellular semiperfect cover of the Schwann cell, a middle two-layered cellular coat, an outer neuropil and an outermost external lamina. The surface of the central perikaryon, which differed from those of the other ganglion cells, was almost entirely covered with one Schwann cell, most probably for isolation from various kinds of external electrical and/or chemical inputs. Dumbbell-shaped vesicles containing endings that were presumed to be sensory, were frequently localized in the outer neuropil of this ganglion. It is likely that this perikaryon belongs to the sensory ganglion cells and so acts as an important factor in the peristaltic reflex arc.

Animals↗

PubMed1988

The ontogeny and fine structure of calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers in the celiac ganglion of rats.

Calcitonin gene-related peptide (CGRP)-like immunoreactivity has been reported to occur in both varicose and non-varicose nerve fibers among and around principal ganglion cells in the celiac ganglion of rats. The present electron microscopic immunohistochemistry revealed a small number of myelinated nerve fibers immunoreactive for CGRP, although most of the immunoreactive fibers were unmyelinated. In the fetal development, CGRP-immunoreactive nerve fibers were first revealed at day 18 of gestation and thereafter gradually increased in number. Both the density and distribution of the immunoreactive fibers within the ganglion similar to those in adult rats were attained by postnatal day 14. This developmental change was compared with that of enkephalin-immunoreactive nerve fibers in the same ganglion. In electron microscopy, the immunoreactive fibers with varicosities were characterized by abundant small clear vesicles mixed with large granular vesicles. These formed numerous axo-dendritic and several axo-somatic synapses with the principal ganglion cells, whereby the immunoreactive fibers were presynaptic. The immunoreactive material was localized in the core of the large granular vesicles as well as in the axoplasm. On the other hand, the immunoreactive fibers without varicosities were characterized by neurofilaments, neurotubules and small mitochondria; small clear or large granular vesicles were rarely found in the immunoreactive fibers. They lay in no direct apposition to adjacent neuronal elements and were, therefore, regarded either as fibers passing through the ganglion or as preterminal portions of the CGRP-immunoreactive varicose terminals.

Animals↗

PubMed2003

The distribution of ganglion cells in the posterior cricoarytenoid muscle of the normal adult rat. A light and electron microscopic study.

We employed by light and electron microscopy to examine the innervation of the posterior cricoarytenoid muscle of the adult rat. The laryngeal nerve was found to often bifurcate into two different bundles. One contained large myelinated (motor) nerve fibers, which were located along the frontal (ventral) muscle surface and entered the muscle at its middle portion to form neuromuscular contacts with individual muscle fibers. The other nerve bundle consisting of clustered ganglion cells (20-30 microm in diameter) and their associated nonmyelinated and small-sized myelinated nerve fibers were mainly found on the dorsal side of the muscle and often ran along the peripheral clefts or depressions of the muscle surface. The nerve bundle often extended side branches, which entered the muscle to be distributed among muscle fibers and near arterioles. Some ganglion cells are considered to enter the muscle, accompanied by branched nerves. Intramuscular ganglion cells and their associated nerve fibers examined by electron microscopy were similar in fine structure to perimuscular ganglion cells and their associated nerve fibers. Nerve fibers contained abundant clear synaptic vesicles which were cholinergic in nature, and often formed synapses with both neighboring axons and the cell body of the ganglion cells. These findings suggest that, in the rat posterior cricoarytenoid muscle, perimuscular and intramuscular ganglion cells exist and may be involved in innervating and contracting smooth muscle cells of the arterioles, thus regulating the blood flow or intravascular pressure.

Animals↗

PubMed1988

Meniscal and ganglion cysts of the knee: MR evaluation.

Meniscal and ganglion cysts frequently present as palpable masses of the knee but occur at different locations than do popliteal cysts. Meniscal cysts also may be discovered incidentally on studies performed for suspected internal derangement. Sixteen cystic lesions of the knee were evaluated with MR, including 11 meniscal cysts and five ganglion cysts. Scans were performed at 1.5 T by using a transmit/receive extremity coil or a receive-only surface coil. Standard spin-echo imaging, including at least one long-TR/asymmetric-TE sequence, was performed in all cases. In six patients, gradient-echo, reduced flip-angle sequences also were done. All meniscal cysts (but none of the ganglion cysts) were associated with horizontal meniscal tears. Cysts were visualized best on the long-TR/TE images; meniscal tears were seen best on the short-TR/TE and long-TR/short-TE images. Meniscal tears and cysts were also seen well on the fast-scanning sequences. Septations were noted in four meniscal cysts and in four ganglion cysts on the long-TR/TE images. Long-TR/TE images were also useful in showing the relationship between the cyst and joint capsule in three of the ganglion cysts. MR imaging is an effective, noninvasive method for evaluating cystic lesions of the knee. Meniscal cysts are always associated with underlying horizontal meniscal tears, which can be detected with MR. Ganglion cysts are not associated with meniscal tears, but may have connections to the joint capsule, which can be detected with MR.

Humans↗

PubMed1997

Fine structure of the apical ganglion and its serotonergic cells in the larva of Aplysia californica.

The apical ganglion is a highly conserved structure present in various marine invertebrate larvae. Although one of the hallmarks of this ganglion is the presence of serotonergic cells, little is known about the structure and function of these cells. We have examined this ganglion in larvae of the marine mollusc Aplysia with light- and electron-microscopic immunocytochemistry. The results indicate that the cellular composition of the apical ganglion of Aplysia is very similar to that of other opisthobranchs. It consists of three classes of sensory cells (ampullary, para-ampullary, and ciliary tuft cells) and of other nerve cell types. Almost a third of the cells in the apical ganglion of Aplysia are serotonergic, and these can be divided into two classes: three para-ampullary and two interneuronal cells. All of the serotonergic cells extend an axon into the central nervous system. The variety of sensory and serotonergic cell types suggests that each type processes distinct attributes of the sensory environment. We argue that the apical ganglion, by virtue of its serotonergic cells, is well-suited to play important roles in the integration of sensory information to achieve proper motor adaptation to variable seawater conditions.

Animals↗

PubMed1991

A Golgi study on the neuronal organization of the habenular ganglion in the red stingray, Dasyatis akajei.

The neuronal organization of the habenular ganglion (HG) was studied in the red stingray using the rapid Golgi method. The HG was made up of the medial (MH) and lateral habenular nucleus (LH), and the former nucleus was further divided into a dorsal, intermediate and ventral subnucleus. Only one type of neurons were observed in the MH, while the LH was composed of two types of neurons. In the left HG cut at the rostrocaudal middle of the ganglion, the LH was located in the dorsolateral region, while the dorsal, intermediate and ventral subnuclei of the MH occupied the dorsomedial, intermediate and ventral portions of the ganglion, respectively. In contrast, the right ganglion seen at this level was composed exclusively of the MH, with the dorsal, intermediate and ventral subnuclei located in the dorsomedial, intermediate and ventral portions, respectively. In the caudal level of the left ganglion, each nucleus was seen almost in the same region as in the level of the rostrocaudal middle, however, three subnuclei of the MH fused with the same subnuclei of the opposite side. In the right ganglion at the caudal level, the LH appeared in the intermediate area. The right LH was far smaller and was located more ventrocaudally than the left LH. On account of the LH, the intermediate subnucleus of the MH was divided into a dorsal and ventral part. The dorsal and ventral subnuclei of the MH remained in the same region as in the rostral level. Thus, the HG of the red stingray exhibited a striking left-right asymmetry, the most remarkable aspect of which was considered to be differences of the size, form and location of the LH between the left and right HG.

Animals↗

PubMed1991

Effect of gentamicin on vestibular ganglion.

The morphological changes of the vestibular ganglion induced by gentamicin (GM) were investigated using light, scanning and transmission electron microscopy. The guinea pigs were injected 4 mg of GM into the middle ear for 5 days. The vestibular ganglion was observed up to 4 weeks after the treatment. Three days after the treatment the degenerative change was first noted in the vestibular ganglion. The degenerative process started from the destruction of mitochondrial cristae and vacuolization of the cytoplasm of the Schwann cell. The cytoplasmic organelles in the ganglion cell gradually deteriorated with swelling of the endoplasmic cisterns as well as Golgi apparatus. At the later stage, the myelin sheath around the ganglion cell disappeared and the number of the cells reduced. These changes of the ganglion cell may be due to the direct action of GM.

Animals↗

PubMed1993

Ultrastructure of the chick vestibular ganglion and vestibular nucleus. A scanning electron microscopic study.

The fine structure of the chick vestibular ganglion and vestibular nucleus was studied in three dimensions using a scanning electron microscope (SEM). NaOH and OSO4 maceration methods were applied to observe the configuration in the mechanically torn specimens. Also, Tanaka's aldehyde prefix OSO4-DMSO-OSO4 method (A-O-D-O method) was applied to observe the intracellular structure in the fractured specimens. The surface of the ganglion cell and the nerve processes were seen to be covered with abundant thin fibrous tissues in the specimen treated with OSO4 maceration. This surface fibrous tissue was completely removed with the NaOH maceration method. As a result, the ganglion cell and nerve processes could be seen to be enveloped in the myelin sheath. In the fractured vestibular ganglion treated by the A-O-D-O method, there were three patterns of perikaryal myelination in the vestibular ganglion cells: heavily myelinated, lightly myelinated, and unmyelinated, respectively. In the perinuclear region of the vestibular ganglion cell, well developed and aggregated cytoplasmic organelles such as endoplasmic reticulum, mitochondria, and Golgi apparati were observed. In the perinuclear region of the Schwann cell relatively large mitochondria were characteristically observed. In the fractured view of the vestibular nerves, most of vestibular fibers were compactly myelinated. In the vestibular nucleus, the gathering of the neuronal cells were observed with the NaOH maceration method.

Animals↗

PubMed1998

Ganglion cysts of the lower extremity: an analysis of 54 cases and review of the literature.

This article reviews 54 consecutive patients with lower extremity ganglion cysts that were surgically removed and histologically confirmed at the Hospital for Special Surgery from 1981 to 1993. Lower extremity ganglia were more common among women. Patients' ages ranged from 13 to 80 years, with the fifth and sixth decades being the most common. Size of the cysts ranged from 3 cm to 10 cm (average: 2.9 cm). Thirty-six (67%) patients had ganglion cysts of the foot and ankle, and 18 (33%) patients had ganglion cysts of the knee area. Four (7%) patients had intraosseous ganglia located in the proximal tibia, patella, and the first metatarsal head. Follow-up data of 40 (74%) patients at an average of 5.9 years (range: 1 to 12.5 years) were obtained. Satisfaction was reported by 83% of patients. Recurrence was seen in 10% of patients, and a report of no or mild pain was given by 86% of the group. Patients who underwent revision ganglion excision had inferior results. Only 25% reported satisfaction and 50% reported no or mild pain. Patients who underwent curettage of an intraosseous ganglion appeared to have superior results. All patients reported satisfaction and no or mild pain. The performance of a concomitant surgical procedure, the anatomic region of the ganglion, or type of postoperative immobilization did not appear to affect the outcome.

Adolescent↗

PubMed1992

[Immunohistochemical studies on the guinea pig's vestibular ganglion cell--with reference to the distribution of substance P and neurofilament].

The immunocytochemical distribution and morphological characteristics of substance P and neurofilament in vestibular end organs and the vestibular ganglion of the guinea pig were investigated. The effect of capsaicin on substance P-like immunoreactivity was also evaluated in this study. Substance P-like immunoreactivity was found in the peripheral region of vestibular end organs and in small or medium size vestibular ganglion cells. Approximately 85% of vestibular ganglion cells showed substance P-like immunoreactivity. Although substance P-like immunoreactivity was depleted in the nasal mucosa and trigeminal ganglion by capsaicin treatment, substance P distributed in the primary vestibular neurons was not affected. In contrast to the distribution of substance P, neurofilament was also found in the primary afferent neurons in the central regions of vestibular end organs. Neurofilament immunoreactive cells, which were larger in size than cells without neurofilament-like immunoreactivity comprised about 34% of vestibular ganglion cells. These immunocytochemical findings suggest that vestibular ganglion cells can be classified on the basis of size and immunocytochemical characteristics.

Animals↗

PubMed1998

Neuropeptide tyrosine-like immunoreactivity (NPY-LI) in ganglion neurons in the adrenal gland of the flat snake (Waglerophis merremii).

In previous morphological and histochemical studies on the adrenal gland of the flat snake, no data demonstrating the existence of ganglion neurons has been reported. The aim of this paper was therefore to establish the presence of ganglion neurons in the adrenal gland of the flat snake Waglerophis merremii and, further to study their chemical phenotype using immunohistochemistry. Our results showed the presence of cells which were immunolabelled with the neuronal marker neurofilament 10 and were thus identified as large ganglion neurons. These cells were localized in the dorsal ribbon of the gland, suggesting a noradrenergic phenotype, exhibited long processes with a longitudinal direction and co-expressed neuropeptide tyrosine- (NPY) and tyrosine hydroxylase-like immunoreactivities (-LI). In addition, NPY-immunoreactive (-IR) fibers were recognized with a wide distribution throughout the gland whereas vasoactive intestinal polypeptide (VIP)-IR fibers were only observed between clusters of cortical and adrenergic chromaffin cells. No cells containing VIP-LI were detected within the gland. Based on their histochemical phenotype, ganglion cells containing NPY and TH could correspond to ganglion neurons type I of the rat. The possible absence of type II ganglion neurons in the adrenal gland of the snake is discussed.

Adrenal Medulla↗

PubMed2002

Long-term survival of autotransplanted major pelvic ganglion in the corpus cavernosum of adult rats.

PURPOSE: Neurogenic impotence is a common complication after radical pelvic surgery, irradiation or perineal trauma. Neuronal transplantation is a new frontier for treating neurological disorders. We investigated whether the major pelvic ganglion can survive and become functional after being implanted into the corpus cavernosum in adult rats. MATERIALS AND METHODS: Adult male rats (13) were divided into 3 groups and sacrificed at 3 time points, namely 30 (4), 60 (5) and 90 (4) days. All rats underwent excision of the right major pelvic ganglion and left cavernous nerve. The right ganglion was implanted into the right crus of the penis. Electrostimulation was applied to the left major pelvic ganglion and cavernous nerve (1.5 mA.) and right crus (10 mA.) at sacrifice. The crural region and left ganglion were then excised for immunostaining of neuronal nitric oxide synthase (nNOS), protein gene product 9.5 and growth associated protein 43. Image analysis was used to calculate the area stained in pixels. Electron microscopy of the implanted area was performed to assess neuronal survival. RESULTS: Although the degree varied, all neuronal implants survived after transplantation. The response to electrostimulation was insufficient to produce erection. No difference was noted among the areas of nNOS staining when specimens from the 3 time points were compared. The area of expression of nNOS, protein gene product 9.5 and growth associated protein 43 was larger in the implanted area than in the surrounding cavernous tissue. Under electron microscopy most surviving implants showed normal ultrastructure, although areas of fibrotic replacement were seen in several implants. CONCLUSIONS: Our results show that the autotransplanted major pelvic ganglion expresses nNOS, protein gene product 9.5 and growth associated protein 43, and survived up to 90 days after implantation into the corpus cavernosum. Further studies with fetal neuronal tissue seem warranted.

Animals↗

PubMed1976

On the acetylcholinesterase activity in the vestibular ganglion of the rat.

Acetylcholinesterase was demonstrated in the ganglion cells of the vestibular ganglion of the rat with Karnovsky's method. The acetylcholinesterase content was evaluated after a 24 hours incubation time by means of a three-grade scale. The cell size was determined by a particle size analyser. No correlation between the two values could be established. A comparison with the spiral ganglion showed a slightly lower acetylcholinesterase content in the vestibular ganglion. The content of acetylcholinesterase in the vestibular ganglion cells seems to be lower than in the spinal ganglion cells.

Acetylcholinesterase↗

PubMed1992

The intraglandular submandibular ganglion of postnatal and adult rats. II. A morphometric and quantitative study.

A morphometric study was undertaken on the submandibular ganglion cells in rats of different ages. This showed a direct proportional increase with age in all the variables measured. Mean cross-sectional cell area showed the most dramatic growth, an increase of more than 5-fold between birth and young adulthood. Mean cell diameter and cell perimeter doubled over the same period. The growth of the nucleus, expressed as diameter, was slower when compared with that of the ganglion cells as a whole. The number of intraglandular ganglion cells remained relatively unchanged from birth to young adulthood, ranging from about 3000 to 5000 cells. They were mainly distributed at the hilar region of the submandibular salivary gland, contributing 1/2 to 2/3 of the total ganglion cell population. The second largest cell population was in the intralobular region, which made up about one-third of the population. The least populated region was in the connective tissue of the sublingual salivary gland, which contained only about 5-7% of the total cell number. Cell counts based on the fluorogold labelling method were generally lower than those made after haematoxylin and eosin staining. In the 2-d-old animals, counts of fluorogold-labelled cells were only about half the H & E counts. The discrepancy may be due to the thicker sections used in the fluorogold method, superimposition of cells leading to an underestimation of cell numbers. Nevertheless, the fluorogold labelling method provided rapid and reproducible results. Its main advantage is that the labelled ganglion cells emit a bright yellow fluorescence which is readily identified; the other is the simplicity of the procedure, as labelling of ganglion cells can be achieved by the intraperitoneal route.

Aging↗