Imposex in Stramonita haemastoma from coastal sites of Cartagena, Colombia / Imposex em Stramonita haemastoma em locais costeiros de Cartagena, Colômbia

Abstract Imposex is the development of male sexual characteristics caused by the toxic effects of some chemicals that acts as an endocrinal disruptor. Antifouling paints contain these chemicals. Cartagena lacks studies to indicate the extent of imposex in its coastal waters. The aim of this study was to determine the prevalence of imposex in the gastropod Stramonita haemastoma in Cartagena, Colombia. Specimens were collected during 2013 from locations of high and low influence of port activity. Morphometric measurements and the frequency of the occurrence of imposex were registered. The comparison among morphometric variables showed statistically significant differences between the two sites studied. Furthermore, the females of the S. haemastoma species presented an imposex frequency of 93.1% in Birds' Island, Cartagena Bay, compared to 31.8% in La Bocana. The relative penis size index or RPLI (10.145 and 3.231) and vas deferens sequence index or VDSI (2.83 and 1.16), showed possible contamination by organotin compounds in both places.

Resumo Imposex é o desenvolvimento de características sexuais masculinas causadas por poluentes tóxicos de alguns produtos químicos que atuam como desreguladores endócrinos. Tintas anti-incrustantes são as que contêm estes produtos químicos. Cartagena carece de estudos para indicar a extensão do imposex nas suas águas costeiras. O objetivo deste estudo foi determinar a prevalência de imposex no gastrópode Stramonita haemastoma em Cartagena, Colômbia. Os espécimes foram coletados durante 2013 de locais de alta e baixa influência da atividade portuária. Foram registradas as medidas morfométricas e a frequência da ocorrência do imposex. A comparação entre as variáveis morfométricas mostrou diferenças estatisticamente significantes entre os dois locais estudados. Além disso, as fêmeas da espécie S. haemastomaapresentaram uma frequência de imposex de 93,1% na Ilha das Aves, Baía das Cartagena, em comparação com 31,8% em La Bocana. O índice do comprimento relativo do pênis ou RPLI (10,145 e 3,231) e o índice da sequência do vaso deferente ou VDSI (2,83 e 1,16), mostraram possível contaminação por compostos organoestânicos em ambos os locais.

O íon magnésio no tratamento de acidentes causados pelos escorpiöes Tityus serrulatus, T. bahiensis e Centruroides sculpturatus: estudo experimental / Magnesium in the treatment of accidents caused by the scorpions Tityus serrulatus, T. bahiensis and Centruroides sculpturatus: an experimental study

Os efeitos produzidos pelas peçonhas escorpiônicas säo consequentes, em sua maioria, à liberaçäo de acetilcolina (ACh) e catecolaminas. A verificaçäo de que o magnésio (Mg2+) inibe a liberaçäo de ACh em razäo de bloquear o influxo de cálcio nas terminaçöes nervosas, levou-nos a investigar a açäo deste cátion sobre os distúrbios produzidos pelas peçonhas escorpiônicas. Relatamos na presente comunicaçäo a açäo do Mg2+ sobre os efeitos induzidos pelas peçonhas dos escorpiöes Tityus serrulatus, T. bahiensis e Centruroides sculpturatus nas preparaçöes isoladas nervo frênico-diafragma, íleo, canal deferente e átrios de rato e in vivo, em ratos anestesiados com registro da pressäo arterial e do eletrocardiograma. Os efeitos da peçonha dos escorpiöes nas preparaçöes isoladas foram abolidos ou muito atenuados pelo Mg2+. O Mg2+, no entanto, somente antagonizou os efeitos da peçonha de C. sculpturatus no íleo de rato. Em ratos anestesiados, a hipertensäo e arritmias provocadas pela peçonha de T. serrulatus foram revertidas com exclusäo de bradicardia pela injeçäo do Mg2+. A peçonha de C. sculpturatus na maioria das experiências causou hipotensäo e arritmias de pequena gravidade. O Mg2+ reverteu as arritmias, mas causou quedas acentuadas da pressäo arterial. Os resultados da pesquisa sugerem o emprego do Mg2+ em acidentes graves na ausência de hipotensäo e bradicardia, produzidos por T. serrulatus e T. bahiensis. Parece contra-indicado nos acidentes causados por C. sculpturatus em vista de seu efeito acima referido na pressäo arterial.

Plectranthus amboinicus (Lour) Spreng (Orégano francés): efecto antimuscarínico y potenciación de la adrenalina / Plectranthus amboinicus (Lour) Spreng (French origan): antimuscarinic effect and adrenaline increase

Se investigó el efecto del extracto acuoso de P. amboinicus sobre el íleon aislado de curiel y conducto deferente en ratas. El extracto acuoso produjo en el íleon aislado de curiel, un antagonismo colinérgico muscarínico de tipo competitivo y en el conducto deferente en ratas se observó una potenciación de la adrenalina exógena. Además, los resultados en el conducto deferente estimulado eléctricamente en ratas sugieren que el extracto acuoso de la planta inhibe la recaptación intraneuronal de catecolaminas. Los efectos antimuscarínicos y adrenérgicos pueden contribuir a la acción antiepiléptica y representan a la vez una posible actividad antidepresiva

Effect of pinacidil on the contractile response of cyclophosphamide-treated rat vas deferens.

Effect of pinacidil, a K+ channel opener, was studied on contractility of cyclophosphamide-treated rat vas deferens. The mean IC50 value of pinacidil against 1 mmol barium chloride induced rhythmic contractions and 40 mmol potassium chloride induced tonic contractions was significantly (P < 0.01 and P < 0.001, respectively) increased in the cyclophosphamide treated group as compared to the control. The mean EC50 value of norepinephrine (NE) in the presence of pinacidil (10(-6) mol) was significantly (P < 0.001) increased in the cyclophosphamide treated group. These findings indicate that the responsiveness of rat vas deferens smooth muscle to pinacidil is reduced following cyclophosphamide treatment.

Effect of medroxy progesterone acetate and testosterone enanthate on vas deferens of rats.

Effects of medroxy progesterone acetate (MPA; 5 mg/kg) and MPA + testosterone enanthate (TE) (3 mg + 2 mg/kg) were investigated in vas deferens and on fertility (along with reversibility study) for 60 days through histopathology, morphometric and certain biochemical parameters such as total proteins, sialic acid, ATPase, SDH and testosterone. The study revealed for altered histopathology and contratile pattern of vas deferens resulting in reduced fertility. The study also indicated androgen antagonistic effect. These effects were found to be reversible 4 and 3 months after withdrawal of MPA and MPA + TE injections respectively. Thus, both types generated functional sterility in the rat, but MPA affected histophysiology of vasal tissue.

Calcium modulatory properties of O,O-diphenyl O-N-cyclooctyl phosphoramidate [corrected] isolated from Ptychodiscus brevis in rat atria and smooth muscle.

Calcium modulatory activity of a marine toxin has been studied employing in vitro preparations. The toxin induced contracture in rat diaphragm was not modified by denervation, d-tubocurarine and tetrodotoxin (TTX). In contrast, varying concentrations of calcium, EGTA and ryanodine inhibited the contracture significantly. The toxin produced a series of repeating contractions in vas deferens. Experiments with TTX, adrenoceptor blockers and other agents exclude a release of neuromediators or direct stimulation of post synaptic receptors to account for the rhythmic effect in vas deferens. The dependence of rhythmicity on external Ca2+ concentration and inhibiting effect of Mn2+, ryanodine and nifedipine indicate a direct activation of voltage-sensitive calcium channel. The toxin also evoked a similar pattern of response in paced atria mediated through Ca2+ influx.

Inhibitory effects of Diazepam in rat Vas Deferens: role of Calcium

Diazepam and Ro5-4864 effects on noradrenaline-induced rat vas deferend contractions were studied. We investigated whether central or peripheral type benzodiazepine receptors were involved, by studying the effects of the selective central or peripheral benzodiazepine receptor antagonists, flumazenil (Ro 151788) or PK 11195 respectively. Diazepam interactions with GABA, adenosine, theophylline, and hypercalcic medium (3.5mM) were studied. Also, we investigate diazepam effect on KC1 depolarized vas deferens. Results showed that diazepam (10(-4) to 1.7x10(-4) M)) and Ro 5-4864 (10(-5) to 5.5x10(-5)M) inhibited NA-induced vas deferens contractions and that neither flumazenil nor PK 11195 antagonized diazepam or Ro 5-4864 inhibitory effects respectively. GABA, adenosine and theophylline did not modify neither NA vas deferens response nor diazepam inhibitory action. Diazepam effect was significantly reduced in an 3.5 mM calcium medium and KC1 vas deferense was inhibited by diazepam 1.3x10(-5) and 1.3 x 10(-4) M. It is concluded that in rat vas deferens diazepam effect seems to be related with calcium mobilization.

Role of androgenic deprivation on the contractile response to norepinephrine in vas deferens isolated from rats submitted to swimming-stress

O presente estudo objetivou o efeito da castraçäo na resposta contrátil à noradrenalina em ducto deferente de ratos previamente submetidos ao estresse agudo, induzido pela nataçäo forçada. O estresse agudo levou à subsensibilidade à noradrenalina em ductos deferentes provenientes de ratos intactos. Semelhantemente, a castraçäo também induziu subsensibilidade à noradrenalina, mas näo ocorreu subsensibilidade adicional em ductos deferentes isolados de ratos castrados submetidos ao estresse agudo. Os resultados mostraram também resposta diferente à noradrenalina, em termos de responsividade relativa (p), quando os ductos deferentes foram retirados de ratos castrados ou castrados submetidos ao estresse agudo. Sugere-se que os esteróides androgênicos exercem um papel importante na regulaçäo da resposta do ducto deferente à noradrenalina durante a situaçäo de estresse agudo. Este efeito parece envolver mecanismos que atuam na sensibilidade dos receptores adrenérgicos e no sistema de captura neuronal de catecolaminas.

Evidence for catecholamine-depleting action of fluoxetine.

The present investigation was undertaken to study the interaction of fluoxetine with 5-hydroxytryptamine (5-HT) and noradrenaline (NA) in rat anococcygeus muscle and vas-deferens. In rat anococcygeus muscle responses to NA were significantly potentiated after 30 min and 60 min incubation with fluoxetine (2.9 x 10(-9) M). The responses to 5-HT were however, inhibited after 30 min incubation with fluoxetine in this preparation. On rat vas-deferens also, the responses to NA were potentiated after 30 min incubation with fluoxetine. The response to 5-HT were not altered significantly. In rats pretreated with fluoxetine (5 mg/kg, ip) for seven days, the responses to NA were significantly potentiated in rat anococcygeus muscle. Whereas the responses to 5-HT and tyramine were significantly inhibited. The inhibited responses to 5-HT restored back to normal when the anococcygeus muscle was pre-incubated with NA for 30 min.

Effects of intraperitoneal administration of khat extract in albino rats on uterine, vas deferens and phrenic diaphragm

The present study was conducted on normal adult albino rats of both sexes. Their body weight ranged between 200 and 250 gm and the experimental animals received 0.2 ml khat extract by intraperitoneal injection for 5 successive days. The mean height of uterine contractions in the pregnant and non-pregnant control groups were 3.48 +/- 1.244 cm and 1 +/- 0.28 cm respectively and were significantly reduced in the experimental pregnant and non-pregnant groups to 2.2 +/- 0.5 m and 0.33 +/- 0.15 cm respectively. The mean height of vas deferens contractions in the control group was 4.3 +/- 0.836 cm and was significantly reduced in the experimental group to 1.5 +/- 0.547 cm. In the control male group, the mean height of phrenic diaphragm contractions produced by direct and indirect stimulation were 5.8 +/- 0.5 cm and 3.7 +/- 0.8 cm respectively and were reduced significantly in the experimental group to 3.5 +/- 1.2 cm and to 1.4 +/- 0.4 cm. In the control female non-pregnant group the phrenic diaphragm contractions produced by direct and indirect stimulation were 4.8 +/- 0.8 cm and 2.9 +/- 0.5 cm respectively, and were reduced significantly in the experimental group to 3 +/- 1.2 cm and to 1.2 +/- 0.2 cm. In the control pregnant group, the phrenic diaphragm contractions produced by direct and indirect stimulation were 4 +/- 0.6 cm and 2.4 +/- 0.4 cm respectively and were significantly reduced in the experimental group to 1.2 +/- 0.2 cm and to 0.8 +/- 0.3 cm. The results were discussed

Magnesium and reserpine influence norepinephrine sensitivity of vas deferens in rats.

Reserpine induced supersensitivity to norepinephrine (NE) in rat vas deferens was sought by alteration of Mg++ and Ca++ concentration in incubation medium in the absence and presence of EDTA. Vas deferens incubated in Mg++ free and Mg++ excess media showed supersensitivity and subsensivity to NE respectively. Alterations in the sensitivity to NE produced by varying the concentrations of Mg++ were comparatively less. In the presence of EDTA, vas deferens obtained from reserpinized animals showed subsensitivity in normal and Mg++ excess media and supersensitivity in Mg++ free medium. In the presence of EDTA, reserpinized preparations showed slight supersensitivity in normal Mg++ medium, marked supersensitivity in Mg++ free and lesser subsensitivity in Mg++ excess medium. Probably EDTA by more effectively removing Mg++ from the membrane binding sites by chelation makes the membrane permeable to Ca++ leading to supersensitivity to NE (observed only in the presence of EDTA). These results suggest that the failure of reserpine to induce supersensitivity to NE in rat vas deferens may be due to an enhanced antagonism of Mg++ on Ca++ movements in this preparations due to the poor capacity of rat tissue to retain Ca++.

Evidence for an 2-presynaptic blocking activity of levamisole in the isolated rat vas deferens

The effects of levamisole on the sympathetic transmission and the mechanism underlying these effects were investigated in the field- stimulated rat vas deferens. Levamisole [5-80 muM] potentiated the contraction of the vas deferens induced by field stimulation at low and high frequencies [2, 20 Hz] in a concentration-dependent manner. The extent of potentiation at low frequency was greater than that at high frequency. However, noradrenaline-induced contractions were only potentiated at high concentrations of levamisole [40, 80 muM]. The potentiating effect of levamisole on electrically evoked muscle twitches was completely abolished in the presence of yohimbine and only a slight potentiation was obtained with high concentrations of levamisole. Moreover, in the presence of levamisole [20 muM], the concentration-response curve of clonidine was shifted to the right and the ED50 of clonidine was increased by three-fold. Levamisole was capable of recovering the electrically-evoked muscle contraction after being abolished by cocaine. These data provided a strong evidence for an alpha2-presynaptic blocking activity of levamisole in the isolated rat vas deferens and confirmed its reported uptake blocking activity, only at high concentration

Espermatozóides no ducto deferente de ratos tratados com extrato etanólico de Curarea tecunarum / Spermatozoa in deferens duct of rats treated with Curarea tecunarum extract

Curarea tecunarum é uma planta usada por tribos indígenas como contraceptivo. As informaçöes etnobotânicas sugerem que o efeito seja no homem, embora a mulher também tome o chá. Com o objetivo de testar, em ratos, a hipótese de que o extrato etanólico de Curarea tecunarum pudesse interromper a produçäo de espermatozóide, projetou-se este trabalho. Ratos Wistar, adultos, foram tratados por gavage com 100 mg (dose única) e 50 mg (por 5 dias ou por 10 dias consecutivos) de extrato etanólico de C. tecunarum (tratado). Um lote de animais recebeu volume equivalente ao extrato, de água destilada (controle A) e outro lote recebeu do mesmo modo, de álcool 50% (controle B). Os animais foram sacrificados aos 7, 21 e 45 dias após o início do tratamento e, imediatamente após o sacrificio foram colhidas amostras de sêmen (ductos deferentes), que foram examinadas para identificar espermatozóides e verificar a sua motilidade. Os seguintes órgäos foram removidos e pesados: hipófise, vesícula seminal (com glândula de coagulaçäo), próstata ventral e testículo (par). Os animais foram pesados no ínicio do tratamento e na data do sacrifício. Näo se observam alteraçöes com significado biológico no peso dos animais dos diferentes grupos. Os órgäos pesados näo mostraram alteraçöes importantes após o tratamento. Todas as amostras de sêmen continham espermatozóides móveis. Embora sejam necessários estudos para avaliar as condiçöes funcionais do espermatozóide (habilidade para fertilizar e gerar embriöes normais) pode-se concluir que, nas condiçöes experimentais deste trabalho, o extrato etanólico de C. tecunarum näo apresenta efeito tóxico sobre o sistema reprodutor e o peso corporal de ratos e näo lesa, severamente, as células germinativas.

Age-related changes in the neuromodulatory effect of opioid peptides on sympathetic nerve terminals

A alteraçäo, dependente da idade, do efeito neuromodulador da ß-endorfina nos terminais nervosos simpáticos foi estudada na porçäo prostática de vasa diferentia de ratos de 4 e 20 meses. O efeito da ß-endorfina e naloxona sobre a contraçäo induzida pelo estímulo transmural dos terminais nervosos (0.2 Hz, 0.5 ms, metade da voltagem supramáxima) foi analisado. Na ausência da droga näo ocorreram alteraçöes dependentes da idade na contraçäo induzida pelo estímulo nervoso. ß-Endorfina causava inibiçäo dose-dependente da contraçäo muscular. A sensibilidade da inibiçäo pela ß-endorfina duplicava entre 4 e 20 meses. Naloxona potenciava de maneira dose-dependente as contraçöes campo-estimuladas induzidas. A potência da naloxona era seis vezes maior em animais de 20 do que de 4 meses. Os dados deste trabalho säo comparados com as alteraçöes relacionadas à idade na reatividade pós-juncional, e é proposto o desenvolvimento de mecanismos compensatórios da idade no nível pré-juncional

Availability of calcium for noradrenergic contraction of the mouse isolated vas deferens is not altered during tolerance to and dependence on morphine

1. The present study assesses the influence of tolerance to, and dependence on morphine on the availability of Ca2+ for contraction of the mouse isolated vas deferens induced by noradrenaline (NA). 2. Reducing Ca2+ content in the bathing solution from 2.5 to 1.2 or 0.6 mM significantly reduced the magnitude of NA-induced contractions. This effect was similar in preparations obtained form control and tolerant/dependent mice (P > 0.05 at any Ca2+ concentration). 3. Omission of Ca2+ from the bathing solution caused a rapid and similar loss of responsiveness to a macimally effective concentration of NA (300 micronM) in both groups (t1/2 < 3 min, P > 0.05). 4. Vasa deferentia obtained from control and tolerant/dependent mice were equally sysceptible to non-competitive antagonism of NA-induced contraction by verapamil (3 to 30 micronM; pD2' values of 5.50 and 5.26, rspectively, (P > 0.05 at any concentration of verapamil). 5. Preparations from tolerant/dependent mice displalyed significant supersensitivity to NA, the magnitude of which was not influence by modifying the Ca2+ concentration in the bathing medium (2.6-and 1.7-fold in 0.6 and 2.5mMCa2+, respectively, P < 0.05. 6. I conclude that tolerance to and dependence on morphine are not associated with changes in the availability of Ca2+ for NA-induced contractions of the mouse vas deferens

Structural and ultrastructural alterations of epithelial cells of vas deferens caused by contrast medium

In a attempt to verify experimentally any possible alterations of epithelial cells of vas deferens caused by radiopaque substance, the right and left vasa deferential of 3 rats were injected respectively with saline solution (0.9 per cent NaCl) and Conray-400 (66.8 per cent sodium iodomethamate). 72 hours later, the animals were killed by cranial trauma and histolofical sections and electronmiucrographs of their vasa deferentia were observed. The histological sections of epithelial cells of left vasa deferentia showed a decrease in height and slight changes in stereocilia as compared with those of right contralateral vasa deferentia. Electronmicrographs displayed a reduction in number and size of stereocilia and alterations of many mitochondria in epithelial cells of left vasa deferentia

Gossypol affects the responsiveness of isolated rat myometrium and vas deferens

The effects of gossypol on responsiveness of both rat myometrium and vas deferens were analyzed. In myometrial strips, gossypol (1-30 micronM) produced rightward displacemtns of the cumulative concentration-response curves to acetylcholine, bradykinin and oxytocin, accompanied by reductions in maximal responses. Gossypol (30 micronM) also completely abolished the contractions induced by field stimulation of the rat vas deferens. The IC50 values for gossypol against agonist-uinduced myometrial contractions and field-stimulated vas deferens contractions were similar, ranging between 13 and 18 micronM. These results provide additional evidence that gossypol exerts a direct and irreversible inhibition of the contractility of both male and female reproductive organs

La N-2 cloroetil N-etil-2-bromobencilamina (DSP4) aumenta la liberacion de eH- noradrenalina producida por despolarizacion del terminal nervioso / N-2 chloroethyl N-2-bromobenzylamine (DSP4) increases the 3H- noradrenaline release evoked by nerve despolarization

La administración intraperitoneal del DSP4 en roedores adultos, inhibe la captación de la 3H-NA exógena y reduce el contenido endógeno de NA en el sistema nervioso central y en la captación noradrenérgica desipramina, con el precursor de la NA, la 1-dopa o con inhibidores de la MAO B, previene los efectos neurotóxicos del DSP4. Con el objeto de investigar el mecanismo por el cual DSP4 reduce el contenido endógeno de NA, la liberación del neurotransmisor inducida por despolarización con K+, fue estudiada en cortes de la corteza cerebral de la rata, un tejido sensible a la acción neurotóxica del DSP4. La incubación con DSP4 (10 micromol/1) indujo un aumento de la liberación de NA espontánea y la inducida por estimulación con el K+. En medio libre de Ca++ sólo se incrementó la liberación espontánea. La potenciación de la liberación de NA inducida por el K+ parece estar relacionada con los mecanismos alfa2 adrenérgicos, dado que no se observa aditividad entre la potenciación producida por el antagonista alfa 2 yohimbina y el DSP4. Sin embargo, esta potenciación a través de mecanismos presinápticos no parece estar involucrada en la depleción desarrollada por el neurotóxico, dado que los tratamientos realziados con drogas con afinidad adrenérgicas son ineficaces para previnir la depleción noradrenérgica por el DSP4 en la corteza cerebral. Los resultados obtenidos en el conducto deferente avalan esta hipótesis, dado que en este tejido resistente al efecto deplecionante del DSP4, el compuesto t

Inhibition by dopamine of the neurotransmission in the rat vas deferens

Se investigaron los efectos de agonistas y antagonistas alfa -adrenérgicos y dopaminérgicos sobre los receptores presinápticos de la porción prostática del conducto defrerente de rata. La variable estudiada fue el primer componente (250 ms) de la respuesta motora inducida por estimulación eléctrica de campo (pulso único). Con el objeto de bloquear los sitios de pérdida de las aminas, todos los experimentos se llevaron a cabo en presencia de cocaína 30 micronmol/l e hidrocortisona 28 micronmol/l. Asimismo, se empleó 1-propranolol 0.3 micronmol/l para bloquear los receptores ß -adrenérgiocs. Clonidina, noradrenalina (NA) y dopamina (DA) inhibieron la respuesta motora inducida por la aplicación de un pulso eléctrico. Este efecto fue, para los tres agonistas, dependiente de las concentraciones utilizadas. DA fue 10 y 10**4 veces menos potente que NA y clonidina respectivamente. El agonista selectivo D2, LY 141865, no logró inhibir la respuesta motora inclusive a una alta concentración (30 micronmol/l). Yohimbina (0.1, 0.3 y 1 micronmol/l) antagonizó en forma competitiva el efecto inhibitorio de clonidina, NA y DA, presentando valores similares de -log KB (7.57, 7.68 y 7.09 respectivamente). De manera análoga, idaxozán 0.03 micronmol/l bloqueó el efecto inhibitorio de DA con una potencia similar (- log KB = 7.81) a la de yohimbina. Por otra parte, pimozide 0.21 micronmol/l y Schering 23390 3 micronmol/l antagonizaron el efecto inhibitorio de DA, mostrando una potencia menor que los antagonistas alfa2 -adrenérgicos...