Histochemical localization of monoamines and cholinesterases in Mytilus pedal ganglion

The pedal ganglion is a peripheral ganglion which gives rise to the innervation for both the somatic and visceral organs of the Mytilus foot. In the present study, different histofluorescence methods for the demonstration of monamines (formaldehyde-glutaraldehyde followed by polyethylene glycol embedding; aluminium-formaldehyde; Falck) and acetylcholinesterase histochemistry were applied in order to characterize the neuronal population of the ganglion. The fluorescence methods employed showed that the cortical region of the pedal ganglion is composed of roundish cells; these mainly contained an orange autofluorescent pigment. Yellow-fluorescing cells were scattered in the anterior region of the cortex, but they were more numerous and arranged in clusters in the posterior region. Green-fluorescing cells were mainly located at the border between the cortex and neuropile and in the neuropile itself, where a rich plexus of beaded green-fluorescing fibres was also present. Of the three methods, that using formaldehyde-glutaraldehyde followed by embedding in polyethylene glycol gave the best preservation of morphological details. Acetylcholinesterase histochemistry showed the presence of positive cells and fibres mainly in the anterior region of the ganglion.     

Serotonin-immunoreactive neurones in the brain of Locusta migratoria innervating the corpus cardiacum

Summary The serotoninergic innervation of the corpus cardiacum (CC) of Locusta migratoria was investigated using two antisera against serotonin. A dense network of immunoreactive nerve fibres was present in the storage lobe of the CC. Immunopositive fibres only sporadically crossed the border between the storage lobe and the glandular lobe of the CC. Immunopositive fibres entered the storage lobe of the CC via the nervus corporis cardiaci I (NCCI); NCCII was immunonegative. Unilateral retrograde fillings of the NCCI with the fluorescent tracer Lucifer yellow, followed by antiserotonin immunocytochemistry, revealed about 20 double-labelled neurones in the anterior part of the pars intercerebralis. The double-labelled neurones were scattered between fluorescent non-immunoreactive neurones. Additionally, 5–7 neurones labelled only with Lucifer yellow were found at the ventrolateral side of the tritocerebrum. No immunopositive neurones were observed in the hypocerebral ganglion. Immunopositive fibres from neurones in the frontal ganglion ran via the recurrent nerve and the neuropile of the hypocerebral ganglion into the paired oesophageal nerve. At most, a few immunopositive nerve fibres occurred in the cardiostomatogastric nerves II, which connect the storage lobe of the CC with the paired oesophageal nerve at the caudal end of the hypocerebral ganglion.     

两种软体动物神经系统一氧化氮合酶的组织化学定位

运用一氧化氮合酶(NOS)组织化学方法研究了软体动物门双壳纲种类中国蛤蜊和腹足纲种类嫁Qi神经系统中NOS阳性细胞以及阳性纤维的分布。结果表明：在蛤蜊脑神经节腹内侧,每侧约有10-15个细胞呈强NOS阳性反应,其突起也呈强阳性反应,并经脑足神经节进入足神经节的中央纤维网中;足神经节内只有2个细胞呈弱阳性反应,其突起较短,进入足神经节中央纤维网中,但足神经节中,来自脑神经节阳性细胞和外周神经系统的纤维大多呈NOS阳性反应;脏神经节的前内侧部和后外侧部各有一个阳性细胞团,其突起分别进入后闭壳肌水管后外套膜神经和脑脏神经索。脏神经节背侧小细胞层以及联系两侧小细胞层的纤维也呈NOS阳性反应。嫁Qi中枢神经系统各神经节中没有发现NOS阳性胞体存在;脑神经节、足神经节、侧神经节以及脑—侧、脑—足、侧—脏连索中均有反应程度不同的NOS阳性纤维,这些纤维均源于外周神经。与已研究的软体动物比较,嫁Qi和前鳃亚纲其它种类一样,神经系统中NO作为信息分子可能主要存在于感觉神经。而中国蛤蜊的神经系统中一氧化氮作为信息分子则可能参与更广泛的神经调节过程。     

脉红螺（Rapana Venosa）神经系统解剖的初步研究

本文对腹足纲、狭舌目、骨螺科的脉红螺神经系统的大体解剖和组织学进行了初步研究。脉红螺神经系统头向集中程度较高,神经节愈合现象较为明显。切片上观察,中枢神经节均由神经节被膜、胞体区和神经纤维网构成;形态上相似的神经细胞有集中分布的现象。     

Distribution and ultrastructure of neurosecretory cells in the cerebral ganglion of the earthworm

Neurosecretory (Nsy) cells within the cerebral ganglion of Lumbricus terrestris were classified ultrastructurally. The Nsy cells within the subesophageal ganglion, nerve cord ganglion, and the peripheral nervous system were also examined. A comparative survey of Nsy cells of four other species of oligochaetes, Eisenia feotida, octolasion cyaneum, Dendrobeona subrubicunda, and Allolophora longa, was also carried out. Seven cell types (A1, A2, A3, A4, A5, C, and SEF), distinguished by special cytological and ultrastructural features, were found within the cerebral ganglion. Distribution of these cells inside and outside the cerebral ganglion was studied in detail by light and electron microscopy. The nerve terminals of each cell type were followed into the neuropile region. Exocytosis from cell bodies appears to be the main release mechanism for the Nsy granules, whereas small Nsy vesicles are released through synapses in the neuropile. Peripheral fibers of some cell types (A1, A2, and A3) extend through the capsule to the pericapsular epithelium. It is possible that Nsy cells secrete hormones from their cell bodies and peripheral processes and that their centrally directed axons release modulators/transmitters within the neuropile.     

Fluorescent Histochemistry and Cholinesterase Staining of Sympathetic Ganglia in a Teleost,Gadus morrhua

The anatomy and histochemistry of the sympathetic nervous system in the cod were studied by osmic acid staining, cholinesterase staining and fluorescent histochemistry of ganglia and nerve fibres. Large bundles of fluorescent fibres from the sympathetic ganglia in the head enter the cranial nerves and run with these. These bundles are exceptionally large to the vagi, and the cod vagi may therefore be regarded as vago-sympathetic trunks. All the sympathetic ganglion cells contain specific (acetyl-) cholinesterase, although the degree of staining was variable. The vast majority of cells in the ganglion coeliacum and other anterior ganglia show specific fluorescence of variable intensity. Ganglion cells completely devoid of specific fluorescence are scarce in the anterior ganglia, but abundant in the posterior ganglia associated with the vesicular nerve. A separate and distinct bundle of medullated fibres leaves the sympathetic chain on the left side and spreads in the wall of the left posterior cardinal vein, presumably innervating the chromaffin tissue. Similar fibres on the right side are also present, but do not form a distinct nerve.     

Localization of a substance P-like material in the central and peripheral nervous system of the snail Helix aspersa

Summary A monoclonal antibody against substance P was used for immunocytochemical staining of the central ganglia of the snail Helix aspersa and several peripheral tissues including the gut, reproductive system, cardiovascular system, tentacle and other muscles.Within the central ganglia many neurones, and many fibres in the neuropile and the nerves entering the ganglia, were stained for the SP-like material. The largest numbers of reactive cell bodies were in the pleural ganglia and on the dorsal surfaces of the pedal ganglia. A group of cells was also found, surrounding the right pedal-cerebral connective, that did not fluoresce, but were enveloped by reactive processes terminating directly onto the neurone somata.Specific staining was observed in all peripheral tissues examined and always appeared to be concentrated in nerve terminals. Most particularly these occurred in the heart and aorta, the pharyngeal retractor muscle and the tentacle. Although mostly present in muscular tissues, some fluorescence was also observed in the nervous layer surrounding the retina. The tentacular ganglion also contained immunoreactive cell bodies.     

Immunocytochemical localization of prolactin-like antigenic determinatns in the neuroendocrine system of the honeybee (Apis mellifica)

Summary In the brain of the adult worker bee (Apis mellifica) prolactin-like (PRL) immunoreactive cells were localized in the lateral neurosecretory cell region and the subesophageal ganglion by means of the PAP procedure. These cells emit nerve fibres which pass through the neuropile of the brain to the corpora cardiaca where a great number of immunoreactive axon terminals is present. Tests with antisera against rat pituitary prolactin and human luteinizing hormone were negative. These results indicate that hPRL material is produced in neurosecretory cells of the bee brain and transferred via axons to the corpora cardiaca for storage and subsequent release into haemolymph.This work is part of the Ph. D. thesis of K.P.S.     

扁玉螺中枢神经系统解剖及显微结构观察

对扁玉螺(Neverita didyma)中枢神经系统的大体解剖和显微结构进行了初步研究。结果表明,扁玉螺中枢神经系统包括一对口球神经节、一对脑神经节、一对侧神经节、一对足神经节及一个脏神经节。各神经节均由神经节被膜、胞体区及中央纤维网三部分组成。左右脑神经节之间和左右足神经节之间的联合以及脑-侧、脑-足和侧-足神经节之间的连索均较短。足神经节有明显的分区现象。     

Localization of a SALMFamide Neuropeptide in the Larval Nervous System of the Sand Dollar Dendraster excentricus

Using immunocytochemical methods we describe the localization of serotonin and the SALMFamide peptide, S1 (GFNSALMFamide), during embryonic and larval development of the echinoid Dendraster excentricus. Anti-SI immunoreactivity first appears in the apical ganglion in late gastrulae at the same time as anti-serotonin immunoreactivity. Initially, anti-S1 immunoreactivity is restricted to fibres of the neuropile, but in later feeding stages, cell bodies are also immunoreactive. Anti-S1 immunoreactivity appears as 2–4 cells in the oral ganglion of early prism stage larvae, whereas anti-serotonin immunoreactivity does not occur in the oral ganglion until the 8-arm stage. Anti-S1 immunoreactivity also occurs in diffuse fibres in the oesophagus and in a single fibre encircling the pyloric sphincter of the gut. A reticular network associated with the apical surface of the epithelial cells of the vestibule of the adult rudiment was anti-S1 immunoreactive. In double-labelling experiments, anti-serotonin and anti-S1 immunoreactivity co-localize in the neuropile of the apical ganglion. The distribution of S1, in association with putative sensory cells in the apical and oral ganglia and with muscles of the oesophagus and gut, suggests S1 may have diverse functions in the larval nervous system. The distribution of anti-S1 immunoreactivity in echinoid embryos and larvae supports the proposal that SALMFamide-like peptides are widely shared in echinoderms and potentially have a fundamental role in neural function.     

Gross morphology of the central nervous system of a phytoseiid mite

The general morphology of the central nervous system is analysed in intact females of the predatory mite, Phytoseiulus persimilis (Acari: Phytoseiidae), using a nucleic acid label (YOYO-1) and confocal laser scanning microscopy. The somata of all cells that comprise the synganglion reside in the cortex. The cortex harbours an estimated total of 10,000 cells. The somata are densely packed in the cortex and cells residing in the inner cortex may only occupy about 1.8 μm. As in all Arachnida, the synganglion is divided in a sub- and a supra-oesophageal nervous mass. Both the cortex and the neuropil appear continuous between these two nervous masses. The sub-oesophageal nervous mass mainly consists of the four paired pedal ganglia that are each associated with a leg. The prominent olfactory lobes are ventrally associated with the first pedal ganglia. A small opisthosomal ganglion occupies the most caudal part of the sub-oesophageal ganglion. The rostral part of the supra-oesophageal nervous mass consists of the paired cheliceral and palpal ganglia. The supra-oesophageal ganglion is the largest ganglion in the supra-oesophageal nervous mass and unlike all other ganglia it is not associated with any of the major nerves. It is therefore more likely involved in secondary information processing.     

Ultrastructure of the synganglion in the larval tickAmblyomma americanum (Ixodoidea: Ixodidae)

The synganglion in the larvalAmblyomma americanum consists of a ganglionic mass pierced by the oesophagus. The nervous tissue consisting of an outer cortex and an inner neuropile is surrounded by an external neurilemma. The cortex comprises perineurium glial cells and neurosecretory and non-neurosecretory neuronal cell bodies. The neuropile consists of nerve fibres ensheathed by glial cells. The entire ganglionic mass is enclosed within a sinus of the circulatory system. No investigations using electron microscopy appear to have been made on the synganglion in the tick larval stage.     

Immunocytochemical mapping of FMRFamide-like peptides in the argasid tick Ornithodoros parkeri and the ixodid tick Dermacentor variabilis

FMRFamide-like immunoreactivity was studied in the argasid tick Ornithodoros parkeri and the ixodid tick Dermacentor variabilis using immunocytochemistry based on the peroxidase-antigeroxidase method. FMRFamide-like immunoreactive cells are widely distributed in various regions of the tick synganglion including protocerebral, cheliceral, stomodeal, palpal, pedal I–IV, and opisthosomal regions in both species. However, there is one layer of immunoreactive cells located on the dorsal surface of the postoesophageal part of the synganglion that is found only in D. variabilis. Besides the immunoreactivity within the cell body and its axons, the neuropile and the neural lamella (the extracellular sheath of the synganglion) are rich in immunoreactive materials. Some coxal muscles are innervated by the FMRFamide-like immunoreactive processes of the nerve from the pedal ganglion.     

Distribution of glutamate decarboxylase-like immunoreactivity in the sixth abdominal ganglion of the cockroach Periplaneta americana

Summary An antiserum against glutamate decarboxylase (GAD) of the rat brain was used to locate GAD activity in sections of the nervous system of the cockroach, Periplaneta americana. The sixth abdominal ganglion was chosen because electrophysiological evidence suggests the presence of GABAergic inhibitory synapses in the cereal-giant interneuron system. Groups of somata and numerous fibres and tracts were positively labelled by the GAD antiserum. A posterior group of labelled somata could be identified close to the entry of the cereal nerves. A line of somata clusters lay along a ventro-lateral furrow. Another discrete row of GAD-like cells was located dorso-laterally. Some small cells among the dorsal unpaired neurons were labelled. A small central group appeared under these cells. An abundance of GAD-like processes and transversal tracts were found within the neuropile. The different systems of GABAergic inhibitors in the ganglion are discussed; in particular we show that the fibres of cereal nerve X are not labelled. This demonstrates that the latter act on the giant fibres via interneurons. We suggest that the group that sends axons into the overlapping region between the cereal nerve and the giant fibre could be the inhibitory interneurons involved in this system.     

Post embryonic development of the central nervous system of the spider Argiope aurantia (Lucas)

Volumetric and histological changes of the central nervous system were studied during post embryonic development of a spider, Argiope aurantia. The neural mass of Argiope grows allometrically with respect to volume of the cephalothorax and body weight. In the first instar 46% of the cephalothoracic volume constitutes the neural mass and this is reduced to 4% in the female (9th stage) and 12% in the male (7th stage) spider. Growth curves for the cephalic ganglion, measured at all stages, represent a straight line. The neural mass of females is two and a half times larger than that of the males. The ganglion increased 24 fold in female and 10 fold in male spiders. Addition of neural mass occurs in all stages. The brain volume is greater than that of the subesophageal ganglion in the first two instars. In subsequent stadia, the subesophageal ganglion grows faster, and in females it is finally three times and in males two times larger than the brain. Growth of cortex and neuropile depict exponential curves. Comparison of growth patterns of these shows an inverse relationship during development. While the volume of the cortex is higher in the first two or three stages, the volume of the neuropile is higher in the remaining stadia. The causes for this growth pattern are discussed. Counts of cell numbers show that there is a constant population of neurons throughout the post-embryonic development. The number of nerve cells in females is higher than in males, 11% in the subesophageal ganglion and 58% in the brain. The growth of the cortex is partly accomplished by an increase in cell volume. In male and female spiders the increase in Type-B cells is 20 and 50 fold, while that of large motor neurons is 200 and 600 fold respectively. The motor neurons of 20 μ and above number 63 in male and 916 in female adult spiders. The growth of neuropile occurs through an increase of dendritic arborization and axonal branching. The largest axons measure 1 μ in the first and 16 μ in adult stages. An increase of incoming sensory fibers is also noticed during development. Invasion of neural lamella into cortex and neuropile increases during development. Neural lamella which are 1-2 μ in the first stage grow to 40–100 μ thickness in adult female spiders, near the origin of the main nerves. One type of astral cells, counted in neuropile, increases 10 fold. The appearance of a central body and the beginning of web construction coincide during the second instar. The relationship between these two is discussed.     

The distribution of NADPH diaphorase activity and immunoreactivity to nitric oxide synthase in the nervous system of the pulmonate mollusc Helix aspersa

Enzyme histochemistry and immunocytochemistry were used to determine the distribution of neurons in the snail Helix aspersa which exhibited nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase activity and/or immunoreactivity to nitric oxide synthase (NOS). NADPH diaphorase-positive cells and fibres were distributed extensively throughout the central and peripheral nervous system. NADPH diaphorase-positive fibres were present in all neuropil regions of the central and peripheral ganglia, in the major interganglionic connectives and in peripheral nerve roots. NADPH diaphorase-positive cell bodies were found consistently in the eyes, the lips, the tentacular ganglia and the procerebral lobes of the cerebral ganglia; staining of cell bodies elsewhere in the nervous system was capricious. The distribution of NOS-like immunoreactivity differed markedly from that of NADPH diaphorase activity. Small clusters of cells which exhibited NOS-like immunoreactivity were present in the cerebral and pedal ganglia; fibres which exhibited NOS-like immunoreactivity were present in restricted regions of the neuropil of the central ganglia. The disjunct distributions of NADPH diaphorase activity and NOS-like immunoreactivity in the neurvous system of Helix suggest that the properties of neuronal NOS in molluscs may differ sigificantly from those described previously for vertebrate animals.     

Brain glycogen during non-diapausing and diapausing development of Pieris brassicae larvae and pupae

Summary

Histological and cytological localization of glycogen was studied in the brain of Pieris brassicae larvae and pupae by histochemistry and electron microscopy. The major glycogen deposits were observed in glial cells located between the cortex and the neuropile and also in perineurial cells. The concentrations of brain glycogen were measured in the larvae and the pupae during non-diapausing and diapausing development. In addition, we demonstrated that starvation reduces the density of the brain glycogen deposits as well as the concentrations of glycogen.     

Ganglion cells immunoreactive for catecholamine-synthesizing enzymes,neuropeptide Y and vasoactive intestinal polypeptide in the rat adrenal gland

Immunohistochemistry has been used to demonstrate tyrosine hydroxylase (TH), dopamine--hydroxylase (DBH), phenylethanolamine N-methyltransferase (PNMT), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) immunoreactivities, and acetylcholinesterase (AChE) activity was demonstrated in rat adrenal glands. The TH, DBH, NPY and VIP immunoreactivities and AChE activity were observed in both the large ganglion cells and the small chromaffin cells whereas PNMT immunoreactivity was found only in chromaffin cells, and not in ganglion cells. Most intraadrenal ganglion cells showed NPY immunoreactivity and a few were VIP immunoreactive. Numerous NPY-immunoreactive ganglion cells were also immunoreactive for TH and DBH; these cells were localized as single cells or groups of several cells in the adrenal cortex and medulla. Use of serial sections, or double and triple staining techniques, showed that all TH- and DBH-immunoreactive ganglion cells also showed NPY immunoreactivity, whereas some NPY-immunoreactive ganglion cells were TH and DBH immunonegative. NPY-immunoreactive ganglion cells showed no VIP immunoreactivity. AChE activity was seen in VIP-immunopositive and VIP-immunonegative ganglion cells. These results suggest that ganglion cells containing noradrenaline and NPY, or NPY only, or VIP and acetylcholine occur in the rat adrenal gland; they may project within the adrenal gland or to other target organs. TH, DBH, NPY, and VIP were colocalized in numerous immunoreactive nerve fibres, which were distributed in the superficial adrenal cortex, while TH-, DBH- and NPY-immunoreactive ganglion cells and nerve fibres were different from VIP-immunoreactive ganglion cells and nerve fibres in the medulla. This suggests that the immunoreactive nerve fibres in the superficial cortex may be mainly extrinsic in origin and may be different from those in the medulla.     

Scanning electron microscopy of neurons isolated from the pedal disk and body column of Hydra

Segments of pedal disk and body column were cut from specimens of Hydra littoralis and separated into epidermis and gastrodermis, then macerated to isolate neurons for scanning electron microscopy. Bipolar and multipolar ganglion cells were present in both tissue layers, whereas sensory cells were found only in the gastrodermis. A single cilium projected from the perikaryon of some bipolar and multipolar ganglion cells; the cilium was long in the pedal disk ganglion cells and short in those from the body column. Ganglion cells from the pedal disk had short, thick processes, whereas those from the body column had long, thin neurites. Gastrodermal sensory cells were characterized as unipolar by the presence of an apical cilium near the perikaryon or as asymmetrical bipolar by the presence of a narrow neck region between the perikaryon and cilium. The axon was short in pedal disk sensory cells and long in those from the body column.     

Identification and localization of catecholamines in the nervous system of Limulus polyphemus

The concentrations of various catecholamines in the nervous system of the horseshoe crab Limulus polyphemus have been determined by high-performance liquid chromatography with electrochemical detection. Dopamine, norepinephrine, epinephrine, and their precursor L -Dopa were present in appreciable quantities in discrete regions of the central nervous system and cardiac ganglion. The catecholamines were localized more precisely by use of the glyoxylic-acid-histofluorescence technique of de la Torre and Surgeon (1976). Catecholamine fluorescence appeared in protocerebral and tritocerebral neuropile, including regions of the central body and optic medulla. Posterior to these brain areas, tracts extended through the circumesophageal ganglionic ring and laterally out each of the pedal ganglia. Small clusters of large fluorescent somata were present in the protocerebrum. No fluorescence was observed in the corpora pedunculata.