Neurosecretory Material Research Articles

Effects of abamectin and fipronil insecticides on the brain and compound eyes of the embryo of Heteracris littoralis (Rambur) (Orthoptera: Acrididae)

Chemical pesticides are essentially hazardous. The risks differ from compound to compound, and much of the information on their actions on insect development remains to be captured. The toxicity of abamectin (a macrocyclic lactone, acting on glutamate-gated chloride channels of insects), and fipronil (a phenylpyrazole, disrupting the GABA receptors) was given on embryos of the short-horned grasshopper Heteracris littoralis (Rambur, 1838) for the first time. Abamectin is 66 times more fatal than fipronil. Treated eggs with a sublethal dose gave a reduction up to 51% in hatchability as compared with normal eggs; yet, without any effect on the incubation period. Many embryos have stopped developing at certain developmental stages. The disruptive effects of both the tested chemicals on the brain and the compound eyes were described. The brain and the compound eyes were severely disrupted. The optic lobes appear small in size, and this led to the malformed compound eyes and optic nerves. The brain cells appeared loose and perhaps few in number. The neurosecretory materials carried in the neurosecretory cells were not clear. The neuropil was wide in the normal brain rather than in treated ones. Treated embryos suffered a shrinkage in ommatidia size and number, they are also irregular. Perhaps continued and precise studies should be made to minimize resistance, usually low doses enhance. Continuing studies on the tested pesticides may provide novel insights on their actions for more effective insect control strategies.

Physiological Role of Orexin/Hypocretin in the Human Body in Motivated Behavior: A Comprehensive Review.

Neurohormones are neurosecretory materials released by neurosecretory cells that serve both as neuromodulators in the brain and spinal cord and as circulating regulatory hormones. They serve a wide range of functions, including homeostasis,development, and modulation of neuronal and muscle activity. In the hypothalamus, neurohormones called hypocretins are created that were discoveredin the late nineties. Orexin receptors (OXRs) have been shown to enhance synaptic signaling in the central nervous system at the cellular level.The orexins improve stimulated neural activity in the hippocampus, which, in turn, aids with spatial memory, learning, and mood. They presentthemselves as mediators for the hypothalamic functions. They have been shown to regulate sleep-wake cycles, arousal mechanisms, addiction, sympathetic nerve activity (SNA), blood pressure, and thermogenesis. Its role in storing brown adipose tissue has implications for thermal homeostasis. The significant role of orexins is seen in tumorigenesis when orexin A (OrxA) and orexin B (OrxB) induce apoptosis in fast-growing tumor cells. Orexin-null subjects show clinical narcolepsy, indicating that orexins were responsible for keeping them awake. Orexin microinjections in mice brains stimulated increased physical activity, thus possibly countering diet-induced obesity. Physical activity significantly increased plasma orexin-A levels, which facilitated the process of energy homeostasis. The amount of adrenocorticotropic hormone (ACTH) increases in stress conditions, which further facilitates the release of the stress hormone cortisol. No increase in the ACTH hormone is seen in stressed mice administered with orexin receptor 2 (OX2R) antagonists thus showing orexin's role in stress reaction. As a result of linking hypocretin/orexin to various physiological procedures, increased research into the medicinal potential of drugs targeting these receptors is emerging. We summed up in this review the recent advances in our understanding of how orexin and its receptor system play an essential role in clinical and pathological functions. This research summarizes a new area for research in human medicine, providing the possibility of controlling a vast array of physiological functions through intra-cerebroventricular injections of a single neuropeptide.

The neurosecretory staining in the pleural-pedal ganglion of the Japanese abalone (Ezoawabi), Haliotis discus hannai, and its relationship to reproduction; with a description of a newly observed neurohemal organ

Neurosecretory staining in the pleural-pedal ganglion of the Japanese abalone (ezoawabi), Haliotis discus hannai, was studied during the reproductive cycle. The variation in stain affinity of the cells and amount of neurosecretory material contained in the neurosecretory cells were measured during the study. The pleural-pedal ganglion contained 7 different cell types. The quantity of different cell types in the pleural-pedal ganglion was unusual for a prosobranch gastropod. Cell Types, α- and β-cells, showed neurosecretory staining and the stain intensity varied during the reproductive cycle. α-cells were the most abundant cells in the pleural-pedal ganglion and the quantity of neurosecretory material inside the cell body clearly correlated with gametogenesis. Neurosecretory material in β-cells showed a strong correlation with the induction of spawning. A neurohemal organ (pleural organ) was found in close proximity to the β-cells in the statocyst tissue. The pleural organ is the first ectodermal neurohemal organ reported in a prosobranch gastropod. A nervous connection (stato-pleural nerve) with a possible sensory function was found between the statocyst and the pleural-pedal ganglion.

Morphological study of the pituitary gland of the studanese Nile fish Clarias Lazera

C.
 
 lazera was studied using some standard techniques employed in the study of vertebrate pituitary.
 
 The pituitary gland is attached to the infundibular region of the brain by a cylindrical infundilbular stalk.
 
 The gland is composed of two main divisions; the pars glandularis and the pars nervosa.
 
 The former is subdivided into an anterior, middle and posterior glandular regions.
 
 The anterior glandular region is composed mostly of clusters of acidophils which surround blood capillaries, giving the region a follicular appearance.
 
 The middle region is composed of basophils, acidophils and chromophobes.
 
 The distribution of the three types of cells has no definite pattern.
 
 The basophils are characterized by possessing colloidal globules, and therefore such basophils are described as globular basophils.
 
 The posterior region is formed mostly of dull acidophils, with few interspersed dull faint basophils.
 
 The two types of cells are scattered singly or in groups arround the branches of the pars nervosa.
 
 The pars nervosa, which is the continuation of the infundibular stalk, form a central core around which the three glandular regions of the pituitary gland are arranged.
 
 The processes of the pars nervosa are elaborate, with a fanning root – like nature, in the posterior glandular region and scanty in both the anterior and middle glandular regions.
 
 The pars nervosa appears as a fibrous tissue with scattered nuclei belonging to neuroglia cells.
 
 It is characterized by the colloidal Herring materials, basophil and acidophilic glandular cells.
 
 Infundilbular stalk, which link the floor of hypothalamus and the terminal zone of the anterior glandular region was found to be a thin lamina of nervious tissue with a layer of epindymal cell lining the third ventricle.
 
 The middle glandular region was found to consist of three chromophils cells, only one type of acidophil was identified.
 
 It took both OG and erythrosin.
 
 The other two types were found to be basophilic and they were designated as type 2 and type 3.
 
 Basophils type 3 were PAS, AF positive but AB negative.
 
 The pars nervosa was found to be small, and contained more stainable neuro-secretory materials.

Efficacy of Ozone on Mortality, Super Oxide Dismutases, Nitric Oxide Enzymes and Ultrastructural Alterations on Some Stored Product Insect Larvae in Egypt

Laboratory studies were carried out to determine the efficacy of ozone (O3) technology as a management tool against larvae of Ephestia cautella, Plodia interpunctella, Trogoderma granarium and Tribolium castaneum. In addition, some biochemical changes and ultrastructural alterations in the above-mentioned larvae were studied. Larval mortality of the four species increased as concentration and exposure periods increased. Complete mortality was observed after 8 h. The LT50–99 values of ozone gas against the larvae decreased as concentration increased. Caterpillars were more sensitive to O3 than grubs. Data also showed that the effective effect of ozonation towards the four larval species indicated that not all insects had the same sensitivity to ozone gas. There was a significant increase in super oxide dismutase (SOD) levels in E. cautella and T. castaneum subjected to LT50 of ozone. Moreover, there was a significant decrease in nitric oxide concentration in both larvae after LT50 of ozone exposure. Ozone-treated larvae suffered from heterogeneous muscles with degenerated nuclei. The neurosecretory cells were found with accumulated neurosecretory materials. The neuropil glia appeared loose and vacuolated. Antenna appeared with loose sinus, and there were no artery nor trachea found. The mushroom body of brain calyces appeared with distributed Kenyon cells. The cuticular layer was degenerated. The tracheae were collapsed. Thus, ozone gas may be used as a clean and safe agent to fight these pests.

Effects of dehydration and subsequent hydration stress on the cerebral neurosecretory cells of Eudrilus eugeniae (Kinberg, 1867)

Moisture is a limiting factor for the survival and distribution of earthworms. During rainy season earthworms come out from their water-filled burrows and during summer move deeper into the soil to prevent acute desiccational water loss. Moisture loving worms like Eudrilus eugeniae when subjected to the dry soil and then subsequently hydrated, both the types of neurosecretory cells (A and B cells) show contrasting neurosecretory changes. During dehydration stress (2, 4 & 6 hours), both A and B cells deplete, lose their cellular conformity with extensive vacuolation. But in subsequent hydration of desiccated worms for 4 hrs, there is accumulation of neurosecretory materials in both types of cells, chiefly in A cells. The result indicates involvement of both A and B neurosecretory cells during osmotic stress from the perspective of histomorphic variations and secretory dynamics.

Fine structure of neurosecretory cells and sinus gland in the eyestalk of the freshwater crab Travancoriana schirnerae Bott, 1969 (Decapoda: Gecarcinucidae)

This study elucidated the fine structure of neurosecretory cells and sinus gland in the optic ganglia of the freshwater crab Travancoriana schirnerae Bott, 1969 (Decapoda: Gecarcinucidae). The eyestalk ganglion showed the presence of four well defined ganglia arranged below the ommatidium: lamina ganglionaris, medulla externa, medulla interna and medulla terminalis of which the lamina ganglionaris, was devoid of neurosecretory cells. Groups of neurosecretory cells seen distributed along the medulla externa, interna and terminalis regions constitute the X-organs. Electron microscopic observations of the eyestalk ganglia revealed ten types of neurosecretory cells, mostly apolar with a few unipolar and bipolar cells classified according to the size, shape and density of the cell and nucleus, cell organelles/inclusions, together with the arrangement and properties of chromatin. These cells were characterized by the presence of large nuclei with unusually condensed chromatin, inclusions like vacuoles and vesicles of varying size, shape and density and organelles like Golgi, endoplasmic reticulum, ribosomes and mitochondria and neurosecretory material. The sinus gland of T. schirnerae was positioned laterally between the externa and interna regions, composed of axonal endings of the neurosecretory cells of the optic ganglia with interspersed glial cells. The axon terminals were enclosed with several small to large membrane bound homogenously dense neurosecretory granules which also occur in the preterminal areas of the axons. Based on size, shape and density of granules and axoplasmic matrix, seven terminal types could be distinguished in the sinus gland of T. schirnerae. Mostly, the granules contained in a terminal were of the same type; rarely, the same terminal enclosed granules of varying size, shape and density. The neurosecretory cell types and axon terminal types represent the types of neurohormones they contained. A precise knowledge of the morphology and cytology of neurosecretory cells in the XO-SG complex of the eyestalk that secrete neurohormones controlling major physiological processes such as growth and reproduction is imperative for successful captive breeding of a species of aquaculture potential.

Thiodan stress on brain neurosecretory cells of the earthworm Eudichogaster kinneari: A Histological profile

Adult Eudichogaster kinneari were exposed to a safe concentration (0.003 ppm) of thiodan for twenty days to evaluate the effects on neurosecretory cells of cerebral and sub pharyngeal ganglion of brain. Brain was severely affected by exposure of above insecticide causing denatured neurosecretory cells due to vacuolization and liquification in cytoplasm, nucleoplasm, in neurosecretory material and in neuropile. Irregular shape of neurosecretory cells were seen, viz- uneven stain, disorderly thickened and broken cell membrane was seen at many places. Most of the neurosecretory material became fragmented and accumulated around the nucleus. Ultimate atrophy of whole histological architecture of neurosecretory cells in both the ganglion of brain was seen. Significant reduction was observed in diameter of cell area, nuclear area, cell length and axon length of neurosecretory cells (p

Changes in the hypothalamus in relation to testicular cells during growth, maturation and spawning phases in the brackishwater teleost Liza parsia (Hamilton, 1822)

In the present investigation, different cell types in the hypothalamus of the goldspot mullet Liza parsia (Hamilton, 1822) were characterised on the basis of their arrangement, distribution and tinctorial properties. The hypothalamic neurosecretory system of L. parsia is made up of two nuclei rich areas viz., nucleus pre-opticus (NPO), nucleus lateralis tuberis (NLT) and their axonal pathways. The NPO is vertically organised and the cells are arranged in an oblique plane on either side of the third ventricle. The larger cells viz., pars magnocellularis (PMC) are dorsally placed whereas smaller cells, pars parvocellularis (PPC) are placed ventrally to the third ventricle. Fine thread like axons stained with chrome-alum-haematoxylin-phloxine (CAHP) extend from preoptic cells to the close proximity of blood capillaries. Cells of the NLT are paired and situated above the pituitary gland. The cells of NPO and NLT exhibited both quantitative and qualitative variations during different periods of the testicular maturation. During growth and maturation periods, cells of PMC and NLT were characterised by intense staining and dense homogeneous granules along with deposition of neurosecretory materials. During spawning period, slight decrease in staining affinity of the cells of PMC and NLT were recorded. Changes in the testes of L. parsia have been described according to variations in gonadosomatic index (GSI) values and frequency percentages of different male germ cells during growth, maturation and spawning phases.

HISTOMORPHOLOGICAL CHANGES IN THE BRAIN IN RELATION TO OVARIAN CYCLE OF FRESHWATER CRAB, BARYTELPHUSA CUNICULARIS

Ovarian maturation by neurosecretory cells in the brain of freshwater crab, Barytelphusa cunicularis have been examined. The histological scrutiny of the brain of Barytelphusa cunicularis related with three types (A, B and C) of neurosecretory cells, which are classified on the basis of size, shape and tinctorial characters. All these types of cells marked annual cyclic changes of cytoplasmic material in association with ovarian cycle. The activity of these cells has been correlated with the ovarian cycle. They are distinguishable by their size, nature locations, shape, nucleus position, cell measure and the secretory product in the cytoplasm. The result indicates that the neurosecretory A, B and C cells of the brain seen involved in the process of mating ovulation. The neurosecretory materials staining intensity index of these cells is described.

Tannic acid modulates the activity of bombyxin- and PTTH-producing neurons in Lymantria dispar L. (Insecta: Lepidoptera) caterpillars

Lymantria dispar caterpillars were exposed for 3 days to tannic acid, added to the artificial diet in the following concentrations: 1, 2.5 and 5%. Changes in the morphometric parameters of medial A2 bombyxin immunopositive and dorsolateral L2` prothoracicotropic (PTTH) immunopositive neurosecretory neurons (nsn; sizes of six nsn, the size of their nuclei, and quantification of cytoplasm density) were analysed upon caterpillars’ exposure to this allelochemical. Protein band density, obtained by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) electrophoresis, from regions of bombyxin and PTTH molecular mass (Mr) were estimated. A2 nsn decreased in size, while the size of their nuclei did not change significantly. Relative cytoplasm density and relative band density from the bombyxin Mr region (Mr 4–5 kD) were decreased upon exposure to 1% and 2.5% tannic acid, while the addition of 5% tannic acid to artificial diet increased all of these parameters. Results suggested that lower concentrations of tannic acid stimulate the release of neurosecretory material from A2 nsn, most probably bombyxin-like protein. High tannic acid concentration (5%) probably allocates resources towards induction of other stress protective components instead of bombyxin-mediated metabolic stress response mechanisms. In L2` nsn, the size of nsn, nuclei and the relative cytoplasm density were increased, and relative band density from the region of big PTTH form (Mr 11–15 kD) was higher in all treatments in comparison to control. Results indicate that PTTH is synthesised and stored in the cytoplasm of L2` nsn.

Impact of dimethoate on brain of the earthworm Eudicho gaster kinneari (Stephenson): A histological profile

Adult Eudichogaster kinneari were exposed to a safe concentration (0.6 ppm) of Dimethoate for twenty days to evaluate the effects on histoarchitecture of cerebral and sub pharyngeal ganglion of brain. Brain was severely affected with exposure of above insecticide, causing degeneration of neurosecretory cells (NSCs). Initially neurosecretory cells exhibited accelerated neurosecretory activity while repeated treatment led exhaustion of neurosecretory material (NSM). The neurosecretory cells lost their normal shape along with many morphological alterations, vacuolization were seen in cytoplasm, nucleoplasm, neurosecretory material and in neuropile, ultimately caused imbalance and lethal effect. Size enhancement in cell area, nuclear diameter, cell length and axon length of neurosecretory cells (p>0.001) were observed significantly.

Cytology and Histology of the Cerebral Neurosecretory Systems in some Tropical Earthworm Species

The cerebral ganglia of tropical earthworms, Metaphire houlleti, Metaphire posthuma (Megascolecidae), Eutyphoeus gammiei (Octochaetidae) and Eudrilus eugeniae (Eudrilidae) revealed mainly two categories of neurosecretory cells (NSCs) – A cells and B cells. Thick cortical tier of A cells stained intensely with AF and were differentiated into A1, A2 and A3 types on the basis of their shape, size and location. The sub-cortical B cells, lying close to the neuropile stained lightly with AF. While the axons of A1 cells discharged neurosecretory material (NSM) beneath the perineurium, those of A2, A3 and B cells generally transported NSM at the margin of the neuropile forming “accumulation zone”. Our present study revealed that in earthworms, in absence of any well-defined neurohaemal organ, there was a phenomenal deposition of NSM in the “accumulation zone” or tissue spaces beneath the highly vascular perineurium from where the secretion readily entered the capillaries by diffusion to meet the physiological demand of the animal.

Adjustment of L1 neurosecretory neuron activity in response to different stressors in gypsy moth caterpillars

Gypsy moth caterpillars were exposed to an increased rearing temperature of 35?C and diet, supplemented with Cd, a heavy metal pollutant, and tannic acid, a plant secondary metabolite. After 3 days? exposure to stressors, changes in the number, morphometric parameters of L1 neurosecretory neurons (nsn) (sizes of the nsn and their nuclei), and the quantity of neurosecretory material in the cytoplasm of the neurons were estimated. Acute exposure to the high temperature of 35?C induced increases in the number of L1 nsn, their size and the size of their nuclei with prolonged exposure time. After acute exposure to different Cd concentrations, the number of L1 nsn was reduced, their size increased and the size of their nuclei decreased. Together with the enhanced relative density of the cytoplasm, our results point to an intensive synthesis and retention of neurosecretory material in the neurons. The relative density of the neurosecretory material in the cytoplasm increased at the thermal treatment, suggesting intensive synthesis and secretory activity in L1 nsn. Caterpillars reared on an artificial substrate with the addition of high concentrations of tannic acid (TA) showed a decreased number of nsn, increased cell size and decreased size of their nuclei. The reduction in the relative density of the cytoplasm led us to conclude that this treatment induced a high synthetic activity of L1 nsn.

Temperature-induced stress response in Lymantria dispar neurosecretory neurons

The release of neurosecretory material from A2 neurosecretory neurons (NSNs) was stimulated in Lymantria dispar fourth instar caterpillars exposed to a temperature of 35 °C for 1, 12, and 24 h, as well as those allowed recover after exposure (12 h at 35 °C, then 12 h at 23 °C). The levels of 2 protein forms with the same molecular mass as bombyxin (3-4 and 4-5 kDa) increased with prolonged exposure to 35 °C. The second band was present only in the groups exposed to this stressor. There was intensified synthetic activity and a low level of secretion in L2' NSNs after exposure to 35 °C. We previously found these NSNs to be immunopositive for prothoracicotropic neurohormone. After this stress, densitometric analysis revealed a decreased amount of the 11-12 kDa isoform (present in the control group). The new isoform (13-15 kDa), expressed after exposure of the insects to a high temperature, increased in amount with prolonged exposure and after recovery at 23 °C. Short-term exposure of caterpillars to high temperatures (35 °C) is a stressor and activates carbohydrate metabolism, while PTTH immunopositive NSNs are secretory-inactive during acute thermal stress regimes.

Morphology and histology of pituitary gland of torrential stream fish Nemacheilus mooreh (sykes)

Pituitary lies ventral to the brain behind optic chiasma in the depression of parasphenoid bone attached to the floor of the mid ventral infundibulum. It is Leptobasic type and show transitional condition between caudo and dorsobasic type, sella turcica, a depression provides space to lodge pitutary with thick connective tissue septum. The pituitary gland is composed of nervous part, the neurohypophysis, and a glandular part, the adenohypophysis. The neurohypophysis develops from the infundibular floor and provides a stalk to pituitary. The distal part of neurohypophysis is brightly stained due to presence of neuro secretory material. The positively stained neurosecretory fibres extensively innervate the pars intermedia and rostral pars distalis. Adenohypophysis develops from the roof of the stomodaeum and is divisible into pars intermedia and pars distalis. Pars distalis is composed of a proximal part containing deeply stained cyanophils and acidophils. The rostral and proximal pars distalis and pars intermedia are arranged in a linear fashion with the rostral pars distalis at the anterior extremity. In N. mooreh, pars intermedia completely surround the distal region of neurohypophysis. The study will provide a deeper insight into morphohistology and cell types of pituitary gland of the freshwater Homalopterid teleost.

NATURE OF THE CARDIOEXCITOR NEUROHORMONE IN AN ARACHNID POECILOTHERIA FASCIATA SCHNEIDER (ARANEIDA)

SUMMARY The heart of Poecilotheria fasciata (Arachnida, Theraphosidas) is regulated by a neurohormone present in the brain and heart tissues. Structural modifications of stainable neurosecretory materials were found in the heart tissue submitted to electrical stimulation. The neurohormone is thermostable and dialysable but is inactivated by trypsin and migrates towards the anode in the electrical field. These properties together with its amino acid composition suggest that the neurohormone may be a peptide.

Sensitivity of gypsy moth neurosecretory neurons to acute thermal stress

In gypsy moth caterpillars exposed to a temperature of 35°C (for 1, 12 and 24 h and caterpillars that were exposed to elevated temperature for 12 h and were allowed to recover for 12 h at 23°C), changes in the brain protein profiles and morphometric characteristics of A1’ medial and L2 lateral protocerebral neurosecretory neurons were analyzed. In all groups, protein bands with a molecular mass corresponding to that of members of heat-shock protein families were detected, indicating that acute exposure to this temperature likely induced the synthesis of HSP. Increased morphometric parameters of A1’ neurons and the large amount of neurosecretory material in the neuron body implicate that the temperature of 35°C is not in the temperature range that exerts stimulatory effects on growth and survival. Changes in the morphometric characteristics of L2 neurosecretory neurons from the lateral part of the protocerebrum, and retention of neurosecretory material in their cytoplasm indicate a low level of secretion.

The paraldehyde fuchsin positive material in corpora cardiaca of Pimpla turionellae L. (Hymenoptera:Ichneumonidae) during egg maturation

The purpose of this study is to examine the effects of the neurosecretory material in corpus cardiacum (CC) on the reproduction of endoparasitic Pimpla turionellae L. For this purpose, the egg maturation and amount of the neurosecretory material in corpus cardiacum of the insects were examined by the serial cross sections. Egg maturation was determined by measuring the terminal oocyte length in the serial cross sections of the ovariole. The egg growth which has observed on the 3 rd day, reached the maximum on 15 th day and after that day the egg laying was observed. The sections of insect brains were stained by paraldehyde fuchsin . The amount of the paraldehyde fuchsin positive neurosecretory (PF + NS) material in CC was at a certain level in the first day of egg development. While terminal oocyte was reaching the maximum length, the amount of the PF + NS material in CC decreased to the minimum level. During the egg laying phase, the amount of the PF + NS material in CC reached the maximum level. These observations give us the idea that the neurosecretory material in corpus cardiacum of this insect may be related to the egg development.

The effects of acute exposure to magnetic fields on morphometric characteristics of bombyxin-producing neurosecretory neurons in gypsy moth caterpillars

Purpose: To examine the effects of acute exposure to strong static magnetic fields and extremely low frequency magnetic fields, on neurosecretory neurons which synthesise insulin-like neurohormone.Materials and methods: Immunocytochemical detection of bombyxin-like material in the protocerebral neurosecretory neurons of Lymantria dispar caterpillars was performed using a monoclonal antibody directed against a synthetic dekapeptide corresponding to the N-terminus of the bombyxin A-chain. Caterpillars were exposed to strong static magnetic fileds (235 mT) and extremely low frequency magnetic fields (2 mT) for three days after moulting into the 4th instar.Results: We report the presence of immunoreactive molecules in A2 type of medial neurosecretory neurons (nsn) in caterpillars' brain of L. dispar. The three-day exposure of caterpillars to stresogenic external magnetic fields changed the size of A2 type nsn, their nuclei and the intensity of protein band in the region of bombyxin molecular mass (4–6 kD) after exposure to extremely low frequency magnetic fields in comparison to control group and group treated by strong static magnetic fields.Conclusion: These are the first data on the influence of external magnetic fields on the polyphagous phytophagous forest pest L. dispar L. (Lepidoptera: Lymantridae) indicating an intensive synthesis of insulin-like neurosecretory material.