The paramedial neurosecretory cells of the suboesophageal ganglion of the cricket,Teleogryllus commodus (Walk.)

Summary Ovariectomy, performed immediately after the final hatch, caused a reduction of stainable (neurosecretory?) material in the paramedial neurosecretory cells (PNC) (A-type) of the suboesophageal ganglion in 10 day-old females of Teleogryllus commodus (Walk.). A concomitant increase in nuclear volume and in the incorporation of ³⁵S-cysteine indicates increased synthesis of neurosecretory material. From these findings it is concluded that more stainable material is secreted in the cerebral neurohaemal organ after Ovariectomy. A functional relationship between the PNC and the ovaries is suggested.     

Chemical induction of mating abnormalities and spermatophore production in the Mediterranean flour moth, Ephestia kühniella

Hexamethyl-melamine (hemel) when injected into male Ephestia kühniella induced mating aberrations expressed as permanent copulation, sterile mating and spontaneous production of spermatophore. Permanent copulation was not caused by blockage or an elongated spermatophore column but probably caused by failure of the male reproductive organs to completely transfer the spermatophore. Spontaneous spermatophore formation was induced by both cholinesterase inhibitors and nerve stimulants, the effect of the former being more pronounced. It was not caused by stress due to poisoning since DDT even at lethal doses did not induce a response. The results suggest involvement of the nervous system in spermatophore production during a normal mating.     

Light,fluorescence and electron microscopic studies on “neurosecretion” in tritonia diomedia bergh (Mollusca,Nudibranchia)

Summary Membrane-limited electron-dense inclusions designated as elementary neurosecretory granules have a characteristic distribution in cerebropleural ganglia of the nudibranch snail Tritonia diomedia. They occur in the neuropile and also in individual nerve fibres, connectives and commissures. These granules have been found neither in perikarya of nerve cells nor in proximal segments of their processes.Specific fluorescence obtained in Tritonia preparations with Sterba's pseudoisocyanin method for neurosecretory products has the same pattern of location.The distribution of stainable material in preparations prepared with ordinary neurosecretory procedures (chrome haematoxylin-phloxin after Gomori-Bargmann and paraldehydefuchsin after Gomori-Gabe) is similar to that described by different authors in other gastropods, but strongly differs from the locationof elementary neurosecretory granules and of pseudoisocyanin-positive material. The adequacy of different histological methods for studying neurosecretion in gastropods is discussed.     

Hypothalamic neurosecretion and photoinduced testicular growth in the tree sparrow,Spizella arborea

Summary To assess the role of the hypothalamic neurosecretory system in the mechanism of photoperiodic control of testicular growth in Spizella arborea, we have examined the effect of (1) photostimulation on the density of paraldehyde-fuchsin-stainable (PAF+) material in the neurovascular zone of the median eminence, and (2) interruption of the hypothalamo-hypophysial (neurosecretory) tract on the photoperiodic testicular response. Birds were captured during midwinter and retained on 8-hr daily photoperiods several months prior to the experiment. Interruption of the neurosecretory tract was effected by a small knife fashioned from stainless steel wire; radiography was employed to facilitate stereotaxic placement of the knife assembly.Extending the daily photoperiod from 8 to 20 hrs induced rapid testicular growth in photosensitive Spizella arborea, but had no consistent effect on the density of PAF+ material in the palisade layer of the anterior median eminence. Whereas some terminal controls showed moderate depletion after 21 days' exposure to 20-hr daily photoperiods, others retained as much or more stainable material than initial controls in which testicular growth was not induced. Moreover, testicular growth was induced at essentially identical rates whether the PAF+ innervation of the anterior median eminence was intact or eliminated to varying degrees. The finding that the rate of photoperiodically induced testicular growth is independent of the density or pattern of accumulation of PAF+material in the neurovascular zone of the median eminence, coupled with the inconstant effect of photostimulation on the density of stainable material therein, strongly suggests that the eminential component of the hypothalamic neurosecretory system is not a part of the mechanism that controls photoperiodic testicular growth in S. arborea.Contribution No. 980, Division of Biology, Kansas Agricultural Experiment Station, Manhattan 66502. This investigation was supported in part by the Undergraduate Research Participation Program (GY-771) of the National Science Foundation. We are grateful to French's Pet Bird Laboratory, Rochester, N.Y., for the parakeet foods, to Richard S. Donham, Michael D. Ruff, Thomas G. Shane, and Philip G. Watt for assisting with field operations, to Mr. Gary R. Dierking for preparing the drawing, and to Mr. Don Pihlaja for assisting with the photomicrography.     

Effects of a synthetic juvenile hormone and some analogues on Ephestia spp. (Lepidoptera: Phycitidae)

Depending on their stage of development, treatment of mature larvae of Ephestia kühniella with a synthetic juvenile hormone resulted in the production of super larvae (which invariably prolonged larval life) and larval-pupal intermediates. When migrating last-instar larvae were treated with the juvenile hormone analogues (JHA) ethyl-3,7, n-trimethyldodeca-2,4-dienoate (ZR512) and isopropyl ii-methoxy-3,7, ii-trimethyldodeca-2,4-dienoate (ZR515), larval-pupal intermediates and pupal mortality were induced. However, when applied topically, ZR515 appeared more effective than ZR512. Both analogues prevented adult emergence when topically applied to the migrating larvae at doses between 28–52 ng. One-day-old pupae were most susceptible while older individuals became less sensitive with age. When larvae pupated in corrugated cardboard rolls were treated with ZR512 those of both E. cautella and E. kiihniella failed to emerge. At an estimated dose of 179 ng cm^-2, ZR515 prevented 77^-6%E. cautella and 100%E. kühniella larvae from emerging as adults. The control of Ephestia by JHA treatment of the pupation sites is discussed.     

Histology of the neurosecretory system and the retrocerebral endocrine glands of the adult migratory grasshopper, Melanoplus sanguinipes (Fab.) (Orthoptera: Acrididae)

Neurosecretory cells of only one type (A, sub type A₂) are seen in adult Melanoplus. Two groups of about 400 cells each are located dorsally in the pars intercerebralis medialis; four cells are located deep within the protocerebrum. We found no neurosecretory cells in other parts of the central or sympathetic nervous systems. In about 10% of the specimens, there was marked asymmetry in the location of the dorsal cell groups, with both of these groups and their axons located in one lobe of the protocerebrum. The nervi corporis cardiaci 1 cross-over in the corpus cardiacum, with the result that material produced by neurosecretory cells on one side of the brain is transported along axons that undergo two chiasmata to the corpus cardiacum of the same side. Stainable secretory material could be traced clearly from the cerebral cells to the corpus cardiacum, and even into the oesophageal nerves from the hypocerebral ganglion. However, stainable neurosecretory material is never present in the corpus allatum or along any of the nerves to this gland.     

Immunofluorescent localization of a substance immunologically related to insulin in the protocerebral neurosecretory cells of the European corn borer

Summary A substance immunologically related to mammalian insulin was demonstrated by immunofluorescence in one of five types of neurosecretory cells in the protocerebrum of the European corn borer, Ostrinia nubilalis. This A₂ cell type contains a secretory material stainable with paraldehyde fuchsin.E.R.A. CNRS n° 850     

Antagonistic response of chlorpromazine and formalin in effecting quantitative changes in the neurosecretory material in the teleost Clarias batrachus (L.).

The hypothalamoneurohypophysial complex of Clarias batrachus maintains an appreciable quantity of neurosecretory material (NSM) under normal conditions. Stress caused by the injection of formalin depletes 70-90% of the stainable NSM from all the component parts of the neurosecretory system, namely the nucleus preopticus (NPO) the neurosecretory tract, and the neurohypophysis. Formalin apparently releases the NSM and stimulates the neurons of the NPO. Chlorpromazine (CPZ) treatment seems to cause quantitative increase of NSM throughout the neurosecretory complex. Simultaneous injection of CPZ and formalin showed that the formalin-induced depletion of NSM could be inhibited by CPZ.     

Neurosecretory cells in the central nervous system of the adult blowfly, Phormia regina Meigen (Diptera: Calliphoridae)

• 1 Neurosecretary cells in the central nervous system of the adult blowfly, Phormia regina Meig., have been examined histologically using the parparaldehyde-fuchsin and Gomori's staining method. Six groups of the neurosecretory cells occur in each hemisphere of the brain, the medial, frontal, lateral A, lateral B, posterior I and posterior II groups. In the subesophageal ganglion, four B-cells and two A-cells are present. In the thoracico-abdominal ganglion, ten A-cells are found in the thoracic region and a total of about 50 A- and B-cells in the hind part of the abdominal region.
• 2 A comparison with the neurosecretory system of two other species of blowfly, Calliphora erythrocephala Meig., Sarcophaga bullata Parker, and the housefly, Musca domestica L., showed similar arrangements and grouping.
• 3 Neurosecretory granules have been observed along the axons originating from the medial neurosecretory cells of the brain, and the thoracico-abdominal ganglion. The granules originating from the medial groups can be traced directly to the corpus cardiacum from which they move to the aorta, crop duct and cardia through axons.
• 4 There is with advancing age a gradual increase in the size of cell bodies and nuclei of the median neurosecretory cells in both females and males of Phormia regina, and also a decrease in stainable granules. This increase in size is dependent on nutrition, with no increase in water alone, a slight increase on sugar, and a maximum increase on sugar and liver. Corresponding increases in size occur in the ovaries in connection with feeding the same substances.

     

Comparative effects of tretamine,tepa, apholate and their structural analogs on human chromosomes in vitro

Breakage of human chromosomes was studied in vitro by treating leukocyte cultures for 8 hours with tretamine, tepa, hempa, hemel, and apholate. The aziridines tretamine, tepa, and apholate effectively induced aberrations; the dimethylamino compounds, hemel and hempa, induced few. Tretamine, the most effective compound, induced aberrations in 78% of the cells; hempa, the least effective, induced aberrations in 14%, even at a 1000-fold greater molar concentration. Abberations occurred in 6% of control cells. The gaps and breaks were induced randomly among cells.     

Die Reaktion des neurosekretorischen Zwischenhirn-Hypophysensystems beim Meerschweinchen nach Röntgenbestrahlung (200 kV)

Zusammenfassung Der Kopf von insgesamt 35 männlichen und weiblichen Meerschweinchen wurde mit Röntgenstrahlen (200 kV) homogen einzeitig bestrahlt. Die Dosen betrugen 500, 1000, 2000 und 3000 R bei einer Dosisleistung von 100 R/min. Nach allen Dosen wird in den neurosekretorischen Kernen des Hypothalamus und im Hypophysenhinterlappen der Bestand an Neurosekret vermindert. Drei Tage nach den Bestrahlungen mit 500 R nimmt das Neurosekret wieder zu und die Menge normalisiert sich bis zum 10. Tag p. irrad. Nach 1000 bis 3000 R sterben die Tiere nach 1 Woche, ohne daß es zur Restitution der Neurosekretbildung kommt.

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The reaction of the neurosecretory hypothalamo-hypophyseal complex in the guinea pig following X-irradiation

Summary The effect of 200 kV X-irradiation on the hypothalamus and hypophysis of 35 (both male and female) guinea pigs was examined 24, 72, 120, and 240 hours after irradiation of the head. Doses of 500, 1,000, 2,000 and 3,000 R were used at 100 R per minute. 24 hours following irradiation at all doses, a decrease of neurosecretory material occurred in the nucleus supraopticus, nucleus paraventricularis, and in the neurohypophysis. 72 hours following irradiation with 500 R, the amount of neurosecretory material increased and normal levels are attained at 10 days. Higher dosages (1,000 to 3,000 R) prevented the increase observed with 500 R at 72 hours; rather, the animals died after 1 week.

     

Neurosecretion in the scorpion Heterometrus swammerdami

Gross morphology, staining characteristics and mapping of the diversity of the neurosecretory cell types in the brain and subesophageal ganglion of the scorpion Heterometrus swammerdami are reported. Special neurosecretory cell groups whose product is stainable with orange-G, acid fuchsin and Heidenhain's hematoxylin are present in the brain. In many of the living isolated neurosecretory cells, the secretory material appears luminous when viewed with dark ground illumination and granular when observed with phase contrast microscope. In the subesophageal ganglion the metameric arrangement of neurosecretory cells is distinct. Neurosecretory product accumulating in specific regions of subesophageal ganglion, and its axonal transport into the dorsal nerves and their termination in cephalic blood vessels apparently representing a storage and release organ of neurosecretion is reported.     

An in situ study of the preoptico-neurohypophysial complex of the freshwater teleost Ciarias batrachus (L.)

Summary The complicated architectural pattern of the preoptico-neurohypophysial neurosecretory system of Clarias batrachus is described using bulk staining procedure. The nucleus preopticus is U-shaped; its limbs constitute the PMC and PPC. The difference in staining intensities noticed among the PMC and PPC might suggest a possible functional difference within the system. Axons of the PMC diagonally pass through the PPC and emerge along with those of the latter to form the right and the left main tracts. The folds and recurrent curves of the neurosecretory axonal tracts, the formation of several pairs of lateral tracts and their union to form median tracts might be devices to increase the storing and releasing capacity for the neurosecretory material. The presence of prominent Herring bodies, and diffuse areas in the neurosecretory tract suggest possible sites of release of neurohormones along the highly vascular hypothalamic region. The common neurosecretory tract is divided into several smaller branches at the level of the pars distalis prior to entering the pars intermedia. Branches do penetrate into the pars distalis, but those entering the rostral component of the pituitary are relatively scarce.Regeneration of the anterior stump of the severed hypophysial stalk to form a neurohypophysis-like organ is also demonstrated in toto with the aid of the bulk staining procedure. A demonstrable increase of stainable neurosecretory material was noticed all along the hypothalamo-neurohypophysial complex of some specimens subjected to complete darkness. Total staining methods could be advantageously used to map the course of recurrent tracts and extra-hypophysial axonal endings. Since the neurosecretory system seems to exhibit a varied structural pattern in different fishes, extension of this study to a larger number of species may throw additional light on the function and the evolution of this important system.I am indebted to Dr. K. N. Udupa, Principal, College of Medical Sciences and Director, Surgical Research Laboratory and Dr. L. M. Singh, Officer in-charge of the Laboratory for providing all facilities and encouragements.     

Hypothalamic neurosecretory activity in relation to the reproductive cycle in the common striped skunk (Mephitis mephitis nigra; order carnivora)

Summary The histological appearance of certain cell groups in the anterior hypothalamus was studied during various phases of the reproductive cycle of the common striped skunk (Mephitis mephitis nigra), a carnivore having a very restricted period of sexual activity. Pronounced changes occur in the amount of stainable neurosecretory material in cells of the supraoptic, paraventricular and anterior hypothalamic nuclei. Material staining with aldehyde fuchsin is stored (or inhibited from being released) in these cells during the sexually quiescent period in both the female and male skunk. The time of approaching sexual activity is characterized by the first signs of release of neurosecretory material from these hypothalamic cells and the peak of estrus and rut coincides with a minimal content of the material.Dedicated to Professor Berta V. Scharrer in honor of her 60th birthday.This study was supported by U.S.P.H.S. Training Grant 5 T 1-GM 102 and Research Grant BN-00840, from the National Institutes of Health. This represents a portion of a dissertation, written under the guidance of the late Professor Ernst Scharrer, and submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Yeshiva University, June, 1965. Preliminary reports of this work were presented at the 78th annual session of the American Association of Anatomists, Miami, Florida, and at the VIIIth International Congress of Anatomists, Wiesbaden, Germany, (Hagedoorn, 1965a, b). I thank Dr. H. W. Deane and Dr. J. Osinchak for their critical reading of this manuscipt.     

Effects of colchicine on release of neurosecretory material from the posterior pituitary gland of the rat

Summary The effect of colchicine on the release of neurosecretory material from the posterior pituitary gland was investigated in the rat in vivo and in vitro. Colchicine was administered subarachnoidally when neurophysin, radiolabelled by injection of (³⁵S) cysteine into the supraoptic nucleus, had accumulated in the neural lobe. Dehydration for 3 days of non-colchicine-treated rats was followed by a 100% reduction of neurophysin-bound radioactivity. When colchicine was given prior to dehydration, the reduction of radioactive neurophysin was less marked. Colchicine treatment alone was likewise followed by a lowering of protein-bound radioactivity in the neural lobe, which may indicate that colchicine, in addition to blocking the rapid axonal transport of neurosecretory material, also impedes the slow transport.The release of radioactive neurophysin in response to depolarizing concentration of potassium in vitro was diminished in the presence of colchicine, the reduction being most pronounced after colchicine treatment in vivo. The biochemical data prove the view that colchicine inhibits the release of neurosecretory material from the neural lobe. The ultrastructural findings support the biochemical data. Thus, colchicine treatment alone or followed by dehydration induced a marked increase in the number of organelles, especially of mitochondria and dense bodies. There was a marked increase in the number of enlarged axons filled with dammed organelles in the infundibulum and neurohypophysis. There was an accumulation of dense core vesicles and microvesicles in the axonal terminals in the neurohypophysis after treatment with either colchicine or colchicine followed by dehydration, which indicates an impediment of the release process. Dehydration alone induced a depletion of the dense core vesicles in the terminals. Out from the combined biochemical and ultrastructural findings possible mechanisms for the action of colchicine are discussed.The present study was supported by grants from Svenska livförsäkringsbolags fond för medicinsk forskning, The Swedish Medical Research Council (No. B73-12X-2543-05B), Magnus Bergvalls stiftelse and from the Medical Faculty, University of Göteborg.Miss Gull Grönstedt is thanked for careful secretarial work and the technical assistance by Mrs. Wally Holmberg, Mrs. Elisabeth Norström and Mrs. Ulla Svedin is gratefully acknowledged. Abbreviations used: NSG = neurosecretory granules; NSN = neurosecretory material; SON = supraoptic nucleus.     

The structure of the hypothalamic neurosecretory cells of Zoarces viviparus L. under the conditions of constant dark and light during the reproductive cycle

Summary The Structure of the hypothalamic neurosecretory cells during their activity in continuous light and dark conditions and depending on the seasonal alteration has been investigated in Zoarces viviparus L. in the level of light and electron microscopy.The depletion of AF- or AT-stainable material, of the elementary neurosecretory granules and the disappearance of smooth-surfaced vesicles occur during April and June. The accumulation of the stanable material as well as the elementary neurosecretory granules and the smooth-surfaced vesicles has been observed in the cell body in late September.An excess increase in number of the smooth-surfaced vesicles of dark-induced animals and light-induced animals kept in a black stained tank is apparent. On the other hand, the disappearance of the elementary granules and the smooth-surfaced vesicles and an enlargement in the reletive nuclear surface of the neurosecretory cells of light-induced animals which were kept in a gray stained tank in April is also evident.Taking into consideration the responsiveness of both the elementary neurosecretory granules and the smooth-surfaced vesicles in relation to the external environment as well as their topographical arrangement in the cell body the possible differences in their origin and function are discussed.Numerous studies indicate that the physical environment is in part responsible for the functional properties of the hypothalamic neurosecretory centers of various vertebrates. In the level of light microscope, it has been repeatedly shown that the neurosecretory cells are activated in the animals subjected to continuous illumination, and in those subjected to long daily photo period (Oksche et al., 1958; Fiske and Greep, 1959; Öztan and Gorbman, 1960; Satyanesan, 1965). The enlargement of the nuclei and the amount of Gomori — or aldehyde fuchsin — stainable material, as well as the enzymatic activity, were used as the criteria of cellular activity in the histological preparation. In the level of electronmicroscope it has been shown that Gomori positive material (Bargmann, 1949) is represented as aggregated elementary neurosecretory granules in the ultrathin sections of neurohypophysis (Bargmann et al,. 1957). Although the fine structure of the hypothalamic neurosecretory cells of various fishes and higher vertebrates have been studied in normal and experimental conditions (Palay, 1960; Lederis, 1962, 1964; Follenius et Porte, 1962; Follenius, 1963; Murakami, 1961–1964; Gansler, 1965; Holmes, 1965) the type of granules and their function still remains as an open question (see Bargmann, 1963; Knowles, 1965).This work was aided by a grant from Nato and the Deutsche Forschungsgemeinschaft.This paper was written as a tribute in honor of the 60th birthday of Prof. Dr. Berta Scharrer.     

Cytophysiological study of neurosecretory and pheromonal influences on sexual development in Ophryotrocha puerilis (Polychaeta,Dorvilleidae)

Summary

Prominent secretory nerve endings are found at the posterior margin of the supraesophageal ganglion in the protandric polychaete, Ophryotrocha puerilis. Solitary juveniles developing as primary males, and then as females, accumulate neurosecretory material in the nerve endings which thereby swell and become filled with granules. Females maintained in mass culture have similar terminals, whereas in secondary males (males which had been females before), these axon terminals are very small and contain no material. When such males are isolated, they accumulate neurosecretory material within the nerve endings and become females. When formerly isolated females are put together, their stores of neurosecretory material are rapidly discharged. Subsequently they lay egg masses and switch to the male state. These effects are mediated by a pheromone released during social contact of formerly isolated females. The complexity of the relationship between neurosecretory activity and sexual state is indicated by the situation in animals maintained in pairs, when both male and female partners have swollen nerve endings packed with secretory material.     

Influence of food on the fecundity ofChrysopa carnea Stephens [Neuroptera,Chrysopidae]

Zusammenfassung Für die Eiproduktion ben?tigtChrysopa carnea Nahrung im ausgewachsenen Stadium. In der vorliegenden Arbeit wurden verschiedene Nahrungssubstanzen ausprobiert (Tab. 1). Die Resultase zeigen eine ziemlich unterschiedliche Wirkung. Die Eiproduktion gint zurück, wenn nur eine künstliche Nahrung (Tab. 2) geboten wurde, w?hrend Blütennahrung die Eizahl stark erh?hte. Die st?rkste Eiproduktion wurde mit künstlicher Nahrung und Blüten erzielt. Für verschiedenen Pollen konnte jedoch eine verschiedene Wirkung nachgewiesten werden.      

Alcohol inhibition of formalin induced depletion of neurosecretory material in the teleost Clarias batrachus (L).

In the normal C. batrachus a fair amount of stainable neurosecretory material (NSM) is always present in all the component parts of the hypothalamo-neurohypophysial (HN) complex. When formalin was injected intraperitoneally 70 to 90% of the NSM was depleted from the HN complex. When ethyl alcohol was administered immediately after formalin treatment, the depletion of NSM was inhibited, and their staining intensity could be compared with those of untreated controls.