Low doses of the pesticide lindane induce protein release by the fat body of female cockroach Blaberus craniifer (Dictyoptera).

In the ovoviviparous cockroach Blaberus craniifer, low doses of the pesticide lindane (1-6 microg/g of body mass) have been implicated in the enhancement of ovarian growth and vitellogenesis onset in headless female ovaries. In order to investigate lindane effects on protein release by the fat body, we used antibodies raised against egg proteins to quantify protein levels in fat body, hemolymph and ovaries of treated-fed or -decapitated females 3- or 5-days -old. In vitro assays used fat body in Grace's medium to quantify the protein amount released in the medium.

Insecticidal effects of Buthus occitanus tunetanus BotIT6 toxin expressed in Escherichia coli and baculovirus/insect cells.

BotIT6 is a neurotoxin polypeptide derived from the venom of the scorpion Buthus occitanus tunetanus (Bot). Its mature form is composed of 62 amino acids. BotIT6 has been reported to be the most potent toxin from Bot venom that has a strict selectivity for insects.

[Reproductive toxicity of lindane].

The present paper bears on the main effects of lindane (gamma isomer of hexachlorocyclohexane) on endocrine and reproductive functions in mammals. This pesticide, once widely used to kill lice and a variety of pests that attack agricultural products, livestock and trees, has been progressively eliminated from many applications since the mid-1970s in Europe or USA, but is still used in the rest of the world. Lindane is absorbed through respiratory, digestive or cutaneous routes and accumulates in fat tissues.

Evidence for a neurotoxic activity in crude venom of the stonefish (Synanceia verrucosa).

The neurotoxic effects of the Synanceia verrucosa venom were investigated in rodents. After intracranial injection in mice (50-125 ng/g), venom induced constant symptoms such as ataxia, circling, partial or complete reversible limbs paralysis, scratching, rolling, sleep-like periods and violent clonic seizure conducing in few seconds to death. EEG alterations occurring in rat brain after intracerebroventricular injection (50-100 microg) were precised.

[Pharmacological properties of fish venoms].

Fish venoms can be lethal for Vertebrates. The effect depends of dose and subject, more than incriminated fish. The most constant symptom is a violent pain; but the serious pharmacological effects are respiratory and heart failure with marked hypotension and cardiac perturbations, neurologic damage, such as seizure and coma.

[Fluctuations of serotonin and its metabolites in the lung and intestinal mucosa in the rat infected with Nippostrongylus brasiliensis].

The influence of parasitism on host biogenic amine levels was investigated in Nippostrongylus brasiliensis infected rats. Amine levels were estimated in tissues surrounding Nematods in their biological environment: the lung and intestinal mucus. D0 being the day of infestation, tissues were obtained at 24, 30 and 45 hrs, and every day between D4 and D14 (when the rat was completely deparasited by the self-cure phenomenon).

Levels of biogenic amines in larvae and adults of the rat hookworm, Nippostrongylus brasiliensis (Nematoda).

Norepinephrine, 5-hydroxytryptophan, octopamine, dihydroxyphenylacetic acid, N-acetyldopamine, dopamine, 5-hydroxyindoleacetic acid, N-acetylserotonin, tyramine, tryptophan and serotonin in larvae (third free stage and parasitic stages) and adult males and females (at defined ages during the intestinal phase) of the parasitic nematode Nippostrongylus brasiliensis were quantified simultaneously by high-performance liquid chromatography with electrochemical detection. Biogenic amine levels depended on the stage, the age and the sex of parasites and on environmental conditions. Their physiological roles in reproductively competent adults of this nematode are discussed in relation to exuviation and egg laying.

Complete amino-acid sequence of the beta-subunit of VTX from venom of the stonefish (Synanceia verrucosa) as identified from cDNA cloning experiments.

A cDNA encoding a subunit of the verrucotoxin (VTX) has been identified from a cDNA library derived from stonefish venom glands. It encodes a polypeptide of 708 amino-acid residues, followed by a 3'-untranslated region of 895 bp long. The ORF contains the complete mature sequence of the beta-subunit of the VTX, as inferred from both the presence of an identical N-terminus sequence and 96% homology among the 506 amino terminus residues found in the partial sequence of the beta-subunit of the stonustoxin from Synanceia horrida (Ghadessy, F.

Cardiotoxicity of verrucotoxin, a protein isolated from the venom of Synanceia verrucosa.

Freshly purified but unstable verrucotoxin (VTX) and a more stable proteic complex of the toxin (p-VTX) were isolated from the venom of the stonefish Synanceia verrucosa and applied to frog atrial fibres. VTX and p-VTX decreased the amplitude and the duration of the stimulated peak tension and accelerated the relaxation phase of the contraction. The negative inotropic effect of p-VTX decreased with increasing the external Ca concentration ([Ca]o) in the Ringer solution.

Enhancement of oocyte growth in the cockroach Blaberus craniifer by a scorpion toxin, charybdotoxin.

We investigated the ovarian response of Blaberus craniifer to charybdotoxin in both imaginal molt headless females and isolated fed females, at three criteria. 1--Vitellogenesis onset, detected by immunocytochemical localisation of sites binding anti-eggs antibodies in the basal oocyte in headless females: 60% of treated females present a positive response. 2--Oocyte length at D4 during vitellogenesis of isolated fed females which was enhanced by 0.

Presence of norepinephrine and other biogenic amines in stonefish venom.

Although fish venoms exert a cardiovascular effect, the presence of adrenergic substances was not previously demonstrated. Chromatographic analysis with electrochemical detection showed the presence of substances co-migrating with norepinephrine, dopamine and tryptophan. Serotonin, which was thought to be implicated in the intense pain following fish envenomation, was not detected.

Does crude venom of the stonefish (Synanceia verrucosa) activate beta-adrenoceptors in the frog heart muscle?

Venom isolated from the stonefish Synanceia verrucosa was assayed in concentrations of 0.07 and 5.7 micrograms/ml on frog atrial fibres and myocytes.

Enzymatic properties of the stonefish (Synanceia verrucosa Bloch and Schneider, 1801) venom and purification of a lethal, hypotensive and cytolytic factor.

The crude venom of the stonefish (Synanceia verrucosa) possesses numerous enzymatic properties (hyaluronidase, eight esterases and ten aminopeptidases). Verrucotoxin was isolated by DEAE and hydroxyapatite chromatography, followed by FPLC gel filtration on Superdex 200 HR 10/30. It was found to be a glycoprotein with a mol.

Proctolin promotes vitellogenesis onset in the imaginal molt decapitated cockroach Blaberus craniifer.

The ovarian response of the imaginal molt decapitated cockroach, Blaberus craniifer, to nanomolar quantities of synthetic proctolin was evaluated. Sites binding anti-egg proteins were detected in the basal oocyte in 67% (18 out of 27) of the treated females, indicating that vitellogenin uptake is mediated by proctolin. The injected concentration of proctolin was consistent with a physiological role.

Levels of ecdysteroid-like material in adults of Nippostrongylus brasiliensis during the intestinal phase.

Total ecdysteroid-like immunoreactive material was assayed and quantified in adults of the parasitic nematode N. brasiliensis during the intestinal phase in the rat in order to detect possible physiological fluctuations in titre. Worms of the same sex isolated from one rat were pooled in order to quantify ecdysteroids using enzyme immunoassay (EIA).

Microtopography of Nippostrongylus brasiliensis (Nematoda: Heligmosomatidae): parasitic larval stages and adults.

Specimens of the rat hookworm, Nippostrongylus brasiliensis (Nematoda) were recovered from lungs (third- and fourth-stage larvae) and intestine (fourth-stage larvae and adults). The following features were studied in the different stages by scanning electron microscopy: cephalic structures, especially sense organs, synlophe, cervical region, and caudal part. The main differences between the third and fourth stages concerned the lip-like structures around the oral aperture, the appearance of the cephalic space with the presence of a cephalic cap in fourth-stage larvae, the pattern of longitudinal ridges, and sexual differentiation.

Microtopography of Nippostrongylus brasiliensis (Nematoda: Heligmosomatidae): free-living larval stages.

Microtopographic features of the various growth stages of the three free-living larval stages of the rat hookworm Nippostrongylus brasiliensis (Nematoda) were surveyed by scanning electron microscopy. These worms have a rounded anterior end and an elongated tail. Cuticular annulations were observed along the body, which also bore two ribbon-like lateral alae.

Effects of ecdysteroids on reproductive physiology of Nippostrongylus brasiliensis (Nematoda) in vivo.

1. The influence of ecdysteroids (ecdysone and ecdysterone) was investigated on the control of reproduction in the parasitic nematode Nippostrongylus brasiliensis in vivo. 2.

Decapitation or starvation raise haemolymph ecdysteroid titres in the ovoviviparous female cockroach, Blaberus craniifer Burm.

1. Decapitating newly emerged Blaberus craniifer females near the prothorax severs connections between the suboesophageal and prothoracic ganglia, thus depriving them of the neuroendocrine cephalic complex (including brain and suboesophageal ganglion) and the anterior end of prothoracic glands (PGs). 2.

[Comparative data on biogenic amines and GABA in three Rodents Filariae].

Detection and quantification of biogenic amines and GABA were carried out on three adult Filariae Litomosoides carinii, Acantocheilonema viteae and Molinema dessetae obtained from Rodents. Catecholamines were under the level of detection. Indolamines and GABA levels depend on species and sex.

Indolamines and onset of vitellogenesis in the imaginal molt-decapitated cockroach Blaberus craniifer Burm.

1. The effects of 5-hydroxytryptamine, 5-hydroxyindoleacetic acid and N-acetyl-5-hydroxytryptamine on oocytes of Blaberus craniifer, in which vitellogenesis was prevented by imaginal molt decapitation, were investigated. 2.

Biogenic amines in newly-ecdysed cockroaches.

1. Simultaneous quantification (HPLC and electrochemical detection) of biological extracts have shown dopamine, N-acetyl dopamine, tryptophan, 5-hydroxytryptamine, a 5-hydroxyindolacetic acid-like substance in nervous tissue and hemolymph of Blaberus craniifer and Periplaneta americana. 2.

Indolamines in the cockroach Blaberus craniifer Burm. nervous system--II. Fed and crowded young males in comparison with females.

1. Indolamines were assayed by HPLC-ECD in nervous tissue of fed and crowded young males Blaberus craniifer Burm. 2.

Biogenic amine levels in the cockroach Blaberus craniifer Burm. nervous system.

1. Apart from octopamine, the same indolamines and catecholamines were detected in the whole nervous system of the cockroach Blaberus craniifer Burm., at the same time.

Biogenic amines and GABA in the larval and adult forms of the nematode Nippostrongylus brasiliensis.

1. Simultaneous detection (HPLC and electrochemical detection) of biological extracts of larval and adult stages of Nippostrongylus brasiliensis was performed in order to assay biogenic amines. 2.