Histomorphometric and immunohistochemical evaluation of the frontal cerebral cortex in diabetic rats after treatment with melatonin / Avaliação histomorfométrica e imuno-histoquímica do córtex cerebral frontal em ratos diabéticos após o tratamento com melatonina

The central nervous system is vulnerable to complications caused by diabetes. These complications lead to increased oxidative stress in the brain, resulting in damage to the cerebral cortex, among other regions. Insulin and hypoglycemic agents are still the most widely used treatments. However, current research with an experimental model of diabetes suggests the use of antioxidants, such as melatonin. Thus, we tested the hypothesis that exogenous melatonin may decrease or prevent the effects of diabetes in the frontal cortex of the rat brain. Fifty albino rats were allocated into five groups: GC = rats without diabetes induction, GD = diabetic rats induced by streptozotocin, GDM = streptozotocin-induced and melatonin-treated diabetic rats, GDI = diabetic rats induced by streptozotocin and treated with insulin, GDMI = diabetic rats induced by streptozotocin and treated with melatonin and insulin simultaneously. Diabetes was induced by intraperitoneal administration of streptozotocin (60mg/kg). Insulin (5U/day) was administered subcutaneously and melatonin (10mg/kg) by drinking water; both treatments last days after. We analyzed animals' weight, the cytokines IL-6 and TNF-α, apoptosis, glycogen, and did morphometry and histopathology of the frontal cortex were analyzed. The results showed that the cerebral cortex of the diabetic animals presented axonal degeneration, reduced number of neurons in the cortex, reduced glycogen, increased IL-6 and TNF-α expression, high apoptotic index, and reduced animal weight and the brain. Treatment with melatonin associated or not with insulin prevented such effects. Thus, we conclude that melatonin associated with insulin may be an alternative for avoiding the impact of diabetes in the brain's frontal cortex.(AU)

O sistema nervoso central é vulnerável a complicações originadas pelo diabetes estresse oxidativo no cérebro e resultando em lesões no córtex cerebral, dentre outras regiões. A insulina e hipoglicemiantes ainda são os tratamentos mais utilizados, entretanto, pesquisas atuais com modelo experimental do diabetes sugerem a utilização de antioxidantes como, por exemplo, a melatonina. Assim, testamos a hipótese de que a melatonina exógena pode diminuir ou prevenir os efeitos do diabetes no córtex frontal do cérebro de ratos. Foram utilizados 50 ratos albinos, divididos em 5 grupos: GC = ratos sem indução ao diabetes, GD = ratos induzidos ao diabetes pela estreptozotocina, GDM = ratos induzidos ao diabetes pela estreptozotocina e tratados com melatonina, GDI = ratos induzidos ao diabetes pela estreptozotocina e tratados com insulina, GDMI = ratos induzidos ao diabetes pela estreptozotocina e tratados com melatonina e insulina simultaneamente. O diabetes foi induzido pela administração intraperitoneal de estreptozotocina (60mg/kg). A insulina (5U/dia) foi administrada por via subcutânea e a melatonina (10mg/kg) pela água de beber. Ambos tratamentos foram realizados durante 30 dias após a indução. Foram analisados o peso dos animais, do cerebro, as citocinas IL-6 e TNF-α, apoptose, glicogênio, além da morfometria e histopatologia do córtex frontal. Os resultados mostraram que o córtex cerebral dos animais diabéticos apresentou degeneração axonal, redução do número de neurônios no córtex, redução do glicogênio, aumento da expressão do IL-6 e TNF-α, elevação do índice apoptótico, além da redução do peso dos animais e do cérebro. O tratamento com melatonina associada ou não a insulina preveniu tais efeitos. Assim, concluímos que a melatonina associada ou não a insulina pode ser uma alternativa na prevenção dos efeitos do diabetes no córtex frontal do cérebro.(AU)

Ultrastructure of the antennal sensilla of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae)

Abstract Insects have several types of sensilla, the characterization of which has been fundamental to understanding the mechanisms of sensory perception in different species. This study aimed to describe the ultrastructure of the sensilla present on the antennae of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae), an important pest of cotton (Gossypium hirsutum L.) crops, as well as their possible variation between sexes. To do this, the antennae of males and females of A. argillacea were analyzed using scanning electron microscopy. Sensilla morphometry was assessed using photomicrographs, from which the lengths and basal and apical diameters of sensilla were measured using the ImageJ program. Seven types of sensilla were identified on the antennae of A. argillacea: sensilla trichodea, sensilla chaetica, sensilla auricillica, sensilla coeloconica, sensilla styloconica, sensilla basiconica, and sensilla Böhm bristles. Differences between the sensilla of males and females were found in their lengths and basal diameters in the distal and proximal regions. This suggests that sensilla functionality may not only vary from one species to another, but also between sexes within the same species. Thus, further transmission electron microscopy and single sensillum recording studies may provide more detailed information on the sensilla of A. argillacea and their functions.

Efeito protetor da melatonina sobre intoxicações por herbicidas / Protective effect of melatonin on poisoning by herbicides

O uso inadequado de herbicidas pode resultar em intoxicações agudas e, às vezes, crônicas por exposição em longo prazo a baixos níveis desses agentes tóxicos, podendo o herbicida atuar também como agentes teratogênicos, mutagênicos, cancerígenos e desreguladores endócrinos, com o aparecimento de doenças neurodegenerativas e distúrbios reprodutivos. Estudos têm revelado que a melatonina tem propriedades antioxidantes, anti-inflamatórias e imunomoduladoras e atua na reprodução. Essa indolamina está entre os agentes que têm se mostrado benéfico em intoxicações por herbicidas, porém não há relatos do uso de melatonina contra intoxicações por Glifosato-Roundup®, muito menos em associação com o Paraquat. Dessa forma, o maior interesse no tratamento das intoxicações por herbicidas, tem-se concentrado em medidas que impeçam ou minimizem as lesões celulares provocadas nos diversos sistemas biológicos. Assim, a melatonina, como antioxidante conhecido, pode ser mais uma alternativa contra as intoxicações por herbicidas associados e/ou individuais.

The inadequate use of herbicides may cause serious and sometimes chronic poisoning due to long exposure to low levels of toxic agents. Herbicides may also be teratogenic, mutagenic, cancerigenous agents and endocrine disruptors, with the occurrence of neurodegenerative diseases and reproduction disorders. Several studies have shown that melatonin has antioxidant, anti-inflammatory and immune-modulating qualities, besides affecting the reproduction system. It is among the agents which are beneficent in poisoning by herbicides even though no reports are extant on the use of melatonin against poisoning by Glyphosate-Roundup® alone or associated with Paraquat. Solutions that prevent or minimize cell lesions caused by several biological systems have been focused upon in the treatment for poisoning with herbicides. Thus, melatonin, a known antioxidant, may be an alternative against the poisoning by single or associated herbicides.

Histoquímica e morfometria da placenta de ratas tratadas com dexametasona / Placental morphometry and histochemistry in rats treated with dexamethasone in early pregnancy

A dexametasona, um glicocorticóide sintético, tem a capacidade de atravessar a placenta aumentando o nível de circulação de corticosteróides da mãe para o feto durante a prenhez. Quando administrada nas fases finais da prenhez pode produzir efeitos indesejáveis na formação da placenta e em vários órgãos da prole. Assim, o presente estudo objetivou investigar o efeito da administração da dexametasona (0,8mg/dia/animal) nos cinco primeiros dias da prenhez, sobre o desenvolvimento placentário de ratas. Utilizou-se 30 ratas albinas, divididas em dois grupos: Grupo I -ratas prenhes sem aplicação de dexametasona, sacrificadas ao 7º e 14º dia; Grupo II -ratas submetidas à aplicação de dexametasona nos cinco primeiros dias de prenhez, sacrificadas ao 7º e 14º dia. Os resultados mostraram que a dexametasona não afetou o número e a histologia dos sítios de implantação, porém, promoveu alteração no disco placentário ocasionando hipertrofia na camada de células trofoblásticas gigantes. Não foram evidenciadas alterações no teor de colágeno, porém houve interferência no metabolismo do glicogênio no espongiotrofoblasto trofospongio. Na morfometria de linhas houve diferença entre os grupos na região de labirinto e células trofoblásticas gigantes, porém a morfometria de pontos só ratificou as alterações percebidas na região do labirinto.

The dexamethasone, a synthetic glucocorticoid, has the ability to cross the placenta by increasing the level of movement of corticosteroids from mother to fetus during pregnancy. When administered in the late stages of pregnancy can produce effects undesirable on placental formation. The present study aimed to investigate the effect of administration of dexamethasone (0.8mg/day/animal) in the first five days of pregnancy, on placental development in rats. We used 30 albino rats, divided into two groups: Group I -pregnant rats without the application of dexamethasone, sacrificed to the 7th and 14th day. Group II -rats subjected to the application of dexamethasone in the first five days of pregnancy, sacrificed to the 7th and 14th day. The results showed that dexamethasone did not affect the number and histology of the implantation sites, but promoted changes in the disk placental causing hypertrophy in trophoblastic giant cell layer. No changes were found in the content of collagen, but there was interference with the metabolism of glycogen in spongiotrophoblast. The morphometry of lines showed, a difference between groups in the region of labyrinth and trophoblast giant cell. However, in morphometry of points there was a difference between groups in the region of labyrinth.

Caracterização dos hemócitos de operários de Nasutitermes coxipoensis(Holmgren) (Isoptera: Termitidae) e avaliação hemocitária após parasitismo por Metarhizium anisopliae / Hemocyte characterization of Nasutitermes coxipoensis (Holmgren) (Isoptera: Termitidae) workers and hemocyte evaluation after parasitism by Metarhizium anisopliae

O objetivo desta pesquisa foi caracterizar morfológica e ultraestruturalmente os hemócitos de operários de Nasutitermes coxipoensis (Holmgren) e quantificar os tipos celulares 24h, 48h e 72h após inoculação com Metarhizium anisopliae. Seis tipos de hemócitos foram identifi cados: plasmatócito, granulócito, esferulócito, prohemócito, adipohemócitos e oenocitóide. Nenhuma alteração na morfologia dessas células foi evidenciada durante os intervalos. Entretanto, houve variações na proporção dos hemócitos em relação à testemunha para esferulócitos, adipohemócitos e oenocitóides, nos três intervalos de avaliação, e para plasmatócitos e granulócitos no intervalo de 48h. As causas potenciais dessa variação e suas implicações são apresentadas e discutidas neste artigo.

We aimed to characterize the morphology and ultrastructure of hemocytes of Nasutitermes coxipoensis (Holmgren) workers and to quantify the cell types 24h, 48h and 72h after inoculation with Metarhizium anisopliae. Six hemocytes types were identified, plasmatocyte, granulocyte, spherulocyte, prohemocyte, adipohemocyte and eonocytoid Hemocytes did not present any morphological alteration at the several observation periods, but they did have a change in their abundance, as observed for spherulocytes, adipohemocytes and eonocytoids at all intervals, and for plasmatocytes and granulocytes at 48h after host inoculation. We argue on the possible reasons and implications of the observed changes.

Morfologia do canal alimentar de lagartas de Spodoptera frugiperda (J E Smith) (Lepidoptera: Noctuidae) alimentadas com folhas tratadas com nim / Morphology of the alimentary canal of Spodoptera frugiperda (J E Smith) Larvae (Lepidoptera: Noctuidae) fed on neem-treated leaves

Pesquisas envolvendo plantas com atividade inseticida evoluíram bastante nas últimas décadas. Entre essas plantas destaca-se o nim, Azadirachta indica, que atua sobre várias espécies de insetos, principalmente Lepidoptera. Sua ação depende da espécie de inseto e concentração aplicada. Uma barreira contra potenciais agentes tóxicos ingeridos com o alimento é o canal alimentar. Assim, a pesquisa teve por objetivo descrever, histologicamente, o canal alimentar de lagartas de Spodoptera frugiperda (J E Smith) alimentadas com folhas tratadas com nim (Neemseto®), nas concentrações 0,5 e 1,0 por cento, e com folhas não tratadas, nos intervalos de 48, 96, 144, 192 e 240h, quantificar as células regenerativas e analisar, histoquimicamente, o produto de secreção do mesêntero. As lagartas foram imobilizadas a baixa temperatura (-4ºC), o canal alimentar foi retirado, fixado em Boüin aquoso, incluído em paraplast e historesina, e os cortes corados por hematoxilina-eosina e ácido periódico de Schiff. Histologicamente, o canal alimentar de S. frugiperda mostrou-se semelhante ao de outros lepidópteros. Alterações morfológicas só foram evidenciadas no mesêntero, sendo a sua intensidade dependente do tempo e da concentração utilizada. Observou-se degeneração do epitélio e redução de células regenerativas e de atividade secretora dessa região, em ambas as concentrações de nim. Essas alterações foram observadas após 96h a 1,0 por cento e 144h a 0,5 por cento. Esses resultados demonstram que o nim (Neemseto®), nas concentrações estudadas, pode ser efetivo para o controle de S. frugiperda por promover alterações morfológicas no mesêntero.

Research involving plants with insecticide activity evolved significantly in the last decades. Among these plants, the neem tree, Azadirachta indica, is commonly used against several insects, mainly Lepidoptera. The neem efficiency depends on the target insect and on the concentration used. A barrier against potential toxic agents ingested together with the food is the alimentary canal. Thus, this research aimed to describe the histology of the alimentary canal of Spodoptera frugiperda (J E Smith) larvae fed on leaves treated with neem (Neemseto®) at a concentration of 0.5 percent and 1.0 percent and non treated, at different intervals (48, 96, 144, 192 and 240h), by quantifying the regenerative cells and analyzing the secretion of the mesenteron histochemically. Larvae were immobilized at low temperatures (-4ºC), the alimentary canal was removed, fixed in Boüin´s aqueous, embedded in paraplast and historesin, sectioned and stained with hematoxilin-eosin and periodic acid- Schiff. The histology of the alimentary canal of S. frugiperda was similar to other lepidopterans. Neem effects on morphology were seen only in the mesenteron, depending on the time and concentration used, such as: epithelium, reduction on regenerative cells and on the secretory activity in this region, confirmed by the histochemistry in both neem concentrations. These alterations were observed after 96h at 1.0 percent, and 144h at 0.5 percent. These results indicte that neem (Neemseto®), at the concentrations studied, may be effective to control S. frugiperda because it promotes meaningful morphological alterations in the mesenteron.

Morphological analysis of neonates of rats treated with dexamethasone in the initial phase of pregnancy / Análisis morfológico de neonatos de ratas tratadas con dexametasona en fase inicial de la preñez

The glucocorticoid dexamethasone has been largely used due to its anti-inflammatory effect. However, several authors report that the excessive exposition to it during pregnancy may cause a retard in the development in several tissues, mainly: liver, lungs and kidneys. But, the majority of the works are done with the application of dexamethasone in the late periods of pregnancy. Because of the lack of researches that evaluate the effects in the beginning of gestation, this paper aimed at evaluating the effect of dexamethasone administered in the initial phase of pregnancy, over the morphology of neonates rat. It was used 10 albino rats (Rattus norvegicus albinus) aged 90 days from the lineage Wistar. The female were coupled and divided in two groups: Group I - rats not submitted to the dexamethasone application (control); Group II - rats submitted to the dexamethasone application in the first 5 days of pregnancy. The results show that the treatment with dexamethasone in a dosage of 0.8mg/Kg during the 5 first days of pregnancy does not produces a weight and height reduction or malformation in the offspring, it does not cause changes in the development of the liver and kidneys of neonate rats, but it leads to a reduction in the denseness of the interalveolar septa causing a higher distension of the alveoli.

El glucocorticoide dexametasona ha sido ampliamente utilizado en virtud de su potencial antiinflamatorio. Sin embargo, varios autores relatan que la exposición excesiva a la dexametasona durante la preñez puede causar el retardo del desarrollo de varios tejidos, principalmente hígado, pulmones y riñones. La mayoría de los trabajos son llevados a cabo con la aplicación de dexametasona en los períodos tardíos de la gestación. El objetivo del trabajo fue evaluar el efecto de la dexametasona, sobre la morfología de ratones neonatos, administrada en la fase inicial de la preñez. Fueron utilizadas 10 ratas Wistar albinas (Rattus norvegicus albinus) con 90 días de edad. Las hembras fueron apareadas y divididas en dos grupos: Grupo I- ratas no sometidas a la dexametasona (grupo control) y Grupo II - ratas sometidas a la aplicación de dexametasona durante los cinco primeros días de preñez. Los resultados mostraron que el tratamiento con dexametasona en dosis de 0,8mg/Kg, a lo largo de los cinco primeros días de la preñez, no produce reducción de peso, longitud o malformación en la prole, tampoco causa alteraciones en el desarrollo del hígado y riñones en los ratones neonatos, pero sí reduce el grosor de los septos interalveolares, causando de esta manera, mayor distensión de los alvéolos.

Effect of the treatment with dexamethasone, for 10 and 15 days, on the fertility in induced rats to polycystic ovaries, by constant illumination / Efecto del tratamiento con dexametasona, por 10 y 15 días, sobre la fertilidad en ratas inducidas a ovarios poliquísticos por la iluminación constante

The present study had the objective of obtaining information about fertility in rats treated with dexamethasone for 10 and 15 days consecutively, to polycystic ovaries, induced by constant illumination. It was used 40 albino rats (Rattus norvegicus albinus), aged 90 days, form the lineage Wistar, which were split, randomly, in four groups, each constituted of 10 animals, namely: Group I - rats kept in a clear/dark cycle for 12/12 hours, and after 100 days submitted to fertility evaluation (control); Group II - rats kept under constant illumination during 100 days and then submitted to fertility evaluation; Group III - rats kept under constant illumination during 100 days, then treated with dexamethasone for 10 days and submitted to fertility evaluation; Group IV - rats kept under constant illumination during 100 days, then treated with dexamethasone for 15 days and submitted to fertility evaluation. The results showed that the number of implanted sites was 38(G1), 37(G2), 32(G3) and 06(G4). The reduction in group IV was due to the high mortality during the experiment, probably because of the prolonged treatment with dexamethasone. These sites presented similar histological aspects. The macroscopic analysis of the neonates haven't shown any indication of malformation. Also, abortion haven't been observed. The treatment with dexamethasone for 10 days in rats does not affect the fertility and the development of the lungs, liver and kidneys of neonates, while the administration during 15 days leads to a high maternal mortality.

El estudio tuvo el objetivo de obtener informaciones sobre la fertilidad en ratas tratadas con dexametasona por 10 y 15 días seguidos, para ovarios poliquísticos, inducidos por iluminación constante. Se utilizó 40 ratas albinas (Rattus norvegicus albinus) con 90 días de edad, del linaje Wistar, las cuales fueron divididas, en cuatro grupos, cada uno constituido por 10 animales: Grupo I - ratas mantenidas en ciclo claro/oscuro de 12/12 horas, y después de 100 días sometidas a la evaluación de la fertilidad (control); Grupo II- ratas mantenidas bajo iluminación constante, durante 100 días, y luego sometidas a la evaluación de la fertilidad ; Grupo III - ratas mantenidas bajo iluminación constante, a lo largo de 100 días, y posteriormente tratadas con dexametasona por diez días, y sometidas a la evolución de la fertilidad; Grupo IV - ratas mantenidas bajo iluminación constante, durante 100 días, en seguida tratadas con dexametasona por 15 días, y sometidas a la evaluación de la fertilidad. Los resultados mostraron que el número de sitios implantados fue 38(GI), 37(G2), 32(G3), y 06(G4). La reducción en el grupo IV fue como consecuencia de la alta mortalidad durante la experiencia, probablemente en función del largo tratamiento con dexametasona. Esos sitios presentaron aspectos histológicos semejantes. El análisis macroscópico de los neonatos no mostró ningún vestigio de malformación. Tampoco fueron observados abortos. El tratamiento con dexametasona por 10 días en ratas, no afecta la fertilidad y el desarrollo de los pulmones, hígado y riñones de neonatos, mientras que la administración por 15 días lleva a una alta mortalidad materna.

Effect of Beauveria bassiana (Bals.) Vuill. and Metarhizium anisopliae (Metsch.) Sorok. on Biological Characteristics of Diatraea saccharalis F. (Lepidoptera: Crambidae) - DOI: 10.4025/actascibiolsci.v30i2.3627 / Efeito de Beauveria bassiana (Bals.) Vuill. e Metarhizium anisopliae (Metsch.) Sorok. sobre características biológicas de Diatraea saccharalis F. (Lepidoptera: Crambidae) - DOI: 10.4025/actascibiolsci.v30i2.3627

The sugarcane borer Diatraea saccharalis F. is considered one of the major sugarcane pests in the American continent. Among control methods, the use of entomopathogenic fungi has been broadly recommended to manage sugarcane pests, including other sugarcane borers. Therefore, this study investigated the effects of different concentrations of Beauveria bassiana (Bals.) Vuill and Metarhizium anisopliae (Metch.) Sorok on biological characteristics of the sugarcane borer. Third-instar larvae of D. saccharalis were fungi-treated using the concentrations of 103, 104 and 105 conidia mL-1. Larvae treated with 105 conidia mL-1 of B. bassiana showed lower survival (56.6%) compared to untreated larvae (90%). Adults originated from treated larvae laid a lower number of eggs and exhibited lower viability, and lived less compared to adults of untreated larvae. Also, larvae treated with 105 conidia mL-1 of M. anisopliae and adults originated from those larvae presented reduced performance compared to untreated larvae. Results indicate that B. bassiana and M. anisopliae are pathogenic to D. saccharalis larvae and affect its biology. Hence, they have potential to be used against this pest.

A broca da cana-de-açúcar Diatraea saccharalis F. é considerada uma das principais pragas nas Américas. Entre os métodos de controle, o uso de fungos entomopatogênicos tem sido amplamente recomendado no manejo das pragas da cana-de-açúcar, incluindo outras lepidobrocas. Assim sendo, este estudo investigou os efeitos de diferentes concentrações de Beauveria bassiana (Bals.) Vuill. e Metarhizium anisopliae (Metsch.) Sorok. sobre parâmetros biológicos da broca da cana-de-açúcar. Larvas de terceiro instar de D. saccharalis foram tratadas com os fungos usando as concentrações de 103, 104 e 105 conídios mL-1. Larvas tratadas com 105 conídios mL-1 de B. bassiana tiveram menor sobrevivência (56,6%), comparadas com lagartas não-tratadas (90%). Adultos originados de larvas tratadas colocaram menor número de ovos, com menor viabilidade, e viveram menos, comparados com adultos originados de larvas não-tratadas. Larvas tratadas com M. anisopliae na concentração de 105 conídios mL-1 e adultos originados destas larvas também exibiram redução no desempenho, comparados aos insetos não-tratados. Os resultados indicam que B. bassiana e M. anisopliae, além de patogênicos às larvas de D. saccharalis, também interferem negativamente na sua biologia, mostrando potencial de uso contra esta praga.

Ultra-estrutura dos ovaríolos de Tropidacris collaris (Stoll) (Orthoptera: Romaleidae) submetido a três fotoperíodos / Ultrastructure of the ovarioles of Tropidacris collaris (Stoll) (Orthoptera: Romaleidae) submitted to three photoperiods

A pesquisa teve o objetivo de avaliar a ultra-estrutura dos ovaríolos de Tropidacris collaris (Stoll), submetido aos fotoperíodos de 10L:14E, 12L:12E e 14L:10E. Foram utilizadas 60 ninfas (30 machos e 30 fêmeas) no último estágio de desenvolvimento, sendo colocados 10 casais em cada tratamento. Trinta dias após atingirem o estágio adulto, as fêmeas foram sedadas com éter etílico e dissecadas sob estereomicroscópio. Os ovaríolos foram fixados em Karnovsky (glutaraldeido 2,5 por cento, paraformaldeído 4 por cento e tampão cacodilato de sódio 0,1 M) e analisados em microscopia eletrônica de transmissão e varredura. Os resultados mostraram não haver influência dos fotoperíodos sobre a ultra-estrutura dos ovaríolos, onde estes apresentaram-se revestidos por uma bainha espessa constituída por um material homogêneo e filamentoso. Na região do filamento terminal observaram-se células com núcleos volumosos, algumas com citoplasma escasso, além de estruturas filamentosas assumindo característica de tecido conjuntivo. No germário, as células germinativas são maiores, com núcleos volumosos, escassos citoplasma e membrana celular com interdigitações. As células foliculares são menores com núcleo pequeno, apresentando ainda projeções citoplasmáticas. No vitelário as células foliculares sofrem modificações na sua morfologia, variando de cúbica a achatada.

The research evaluated the ultrastructure of the ovarioles of Tropidacris collaris (Stoll), submitted to photoperiods 10L:14D, 12L:12D and 14L:10D. Sixty nymphs (30 males and 30 females) in the last stage of development were paired in ten couples in each treatment. Thirty days after adult emergence, the females were immobilized with ethylic ether and dissected under stereomicroscope. The ovarioles were transferred to Karnovsky fixative (2.5 percent glutaraldehyde, 4 percent paraformaldehyde and 0.1 M sodium cacodylate buffer) and analyzed in transmission and scanning electron microscopes. The different photoperiods had no effect on the ovarioles' ultrastructure. Each ovariole is covered by a thick sheath constituted by a homogeneous and filamentous material. In the terminal filament, there are cells with large nuclei, some with scarce cytoplasm and projections cytoplasmatic, besides filamentous structures assuming characteristic of conjunctive tissue. In the germarium, the germ cells are big with large nuclei, scarce cytoplasm and plasma membrane containing interdigitations. The follicular cells are small with a small nucleus, yet presenting cytoplasmatic projections. In the vitellarium the follicular cells suffer modifications in their morphology varying from cubic to flat.

Histological Evaluation of the Induced Endometriosis in Rats, after Treatment with Dexamethasone / Evaluación Histológica de la Endometriosis Inducida en Ratas, Posterior al Tratamiento con Dexametasona

The present research had the purpose to analyze morphologically the sites of endometrial implants on the external area of the musculature of the anterior abdominal wall of female rats, treated with dexamethasone. For so, these 15 albino female rats were used (Rattus norvegicus albinus), of the lineage Wistar with 90 days of age, that were submitted to the induction of the endometriosis, and divided in the following groups: Group I ­ induced female rats to endometriosis and evaluated after 21 days (control); Group II ­ induced female rats to endometriosis and after 21 days, treated with dexamethasone for 10 days; Group III - induced female rats to endometriosis, and after 21 days, treated with dexamethasone for 15 days. The dexamethasone was administered in the dosage of 0,8 mg/day/animal. Our results showed that the chronic inflammatory process in the endometriosis doesn't decrease after treatment with dexamethasone for 10 days, while the treatment with dexamethasone for 15 days reverted the chronic inflammatory process in the endometriosis, besides stimulating the proliferation of glands in endometrial implants.

El objetivo de la investigación fue analizar morfológicamente los sitios de implantes endometriales sobre la región externa de la musculatura de la pared abdominal anterior de ratones, tratados con dexametasona. Para ello, fueron utilizados 15 ratones albinos (Rattus norvergicus albinus), del linaje Wistar, de 90 días de edad, los cuales fueron sometidos a inducción de la endometriosis y divididos en los siguientes grupos: Grupo I ­ ratones inducidos a la endometriosis y evaluados tras 21 días (control); Grupo II ­ ratones inducidos a la endometriosis y tras 21 días, tratados con dexametasona durante 10 días; Grupo III ­ ratones inducidos a la endometriosis, y tras 21 días, tratados con dexametasona durante 15 días. La dexametasona fue administrada en dosis de 0,8mg /día/animal. Nuestros resultados muestran que el proceso inflamatorio crónico en la endometriosis no baja después del tratamiento con dexametasona durante 10 días, mientras que el tratamiento con dexametasona durante 15 días cambió del proceso inflamatorio crónico en la endometriosis y estimuló la proliferación de glándulas en los implantes endometriales.

Evaluation of the estral cycle in rats after treatmen twith dexamethasone for polycystic ovaries, induced by constant illumination / Evaluación del Ciclo Estral en Ratones Después del Tratamiento con Dexametasona para Ovarios Poliquísticos, Inducidos por Iluminación Continua

El objetivo del estudio fue obtener información básica del ciclo estral en ratones tratados con dexametasona, en ovarios poliquísticos, inducidos por iluminación continua. Fueron utilizados 30 ratones albinos (Rattus norvegius albinus) del linaje Wistar, con 90 días de edad, divididos en los siguientes grupos: Grupo I – ratones mantenidos en ciclo claro/oscuro de 12/12 horas,tras 100 días sometidos a la evaluación de la ciclicidad (control). Grupo II – ratones mantenidos bajo iluminación continua, durante 100 días y luego sometidos a la evaluación de la ciclicidad. Grupo III – ratones mantenidos bajo iluminación continua, durante 100 días, después tratados con dexametasona durante cinco días y sometidos a la evaluación de la ciclicidad. Los resultados mostraron que tras 100 días de pruebas, los animales del grupo I presentaron una ciclicidad normal, siendo observadas las cuatro fases de éste. En los animales de los grupos II y III se verificó una mayor incidencia de fase de estro, con el porcentaje de 85 por ciento y 76,50 por ciento, respectivamente, caracterizando el estado de estro permanente. Fue observada la fase de diestro en el 15 por ciento, en el grupo II, y 23,5 por ciento en el grupo III, no siendo observadas las fases de proestro y metaestro. Posterior al tratamiento con dexametasona, se verificó una reducción acentuada en la fase de estro en los animales del grupo III, lo que también fue observado en los animales del grupo II , alcanzando un 34,5 por ciento y 20,85, respectivamente. Hubo incluso aumento de la fase de diestro en el grupo II (64,58 por ciento), y grupo III (75 por ciento). Notamos en esos grupos, la presencia de la fase de proestro en el 0,92 por ciento en el grupo II y 4,15 por ciento en el grupo III, no siendo observada la fase de metaestro. El tratamiento con dexametasona durante cinco días, produce más rápidamente una eventual vuelta del ciclo estral en ratones con poliquistosis ovárica.

The study aimed at obtaining basic information about estrous cycle in rats treated with dexamethasone, for polycystic ovaries, induced by constant illumination. It was used 30 female rats (Rattus norvegicus albinus) from the lineage Wistar, with 90 days years old, divided according the following groups: Group I - rats maintained in a light/dark cycle for 12/12 hours, and after 100 days submitted to the cyclicity evaluation (control); Group II - rats maintained under constant illumination during 100 days and after submitted to the cyclicity evaluation; Group III - rats maintained under constant illumination during 100 days and after treated with dexamethasone for five days, and, then, submitted to the cyclicity evaluation. The results showed that after 100 days of experiment, the animals from group I presented a normal cyclicity, being observed the four phases of the cycle. In the animals of groups II and III, it was observed a higher incidence in the estrous phase, with 85% and 76,5% respectively, characterizing the state of permanent estrous. It was observed the phase of diestrous with 15% in group II, and 23,5% in group III, not being observed the phases of proestrous and metaestrous. After treatment with dexamethasone, it was verified a great reduction in the estrous phases in the animals from group III, what was also observed in the animals from group II, reaching numbers of 34,5% and 20,85%, respectively. Yet, there was an increase in the diestrous phase in group II (64,57%), and group III (75%). It has been noticed in these groups the presence of the proestrous phase with 0,92% in group II and 4,15% in group III, not being observed the metaestrous phase. The treatment with dexamethasone during five days produces, more rapidly, a possible retake of the estrous cycle in rats with ovarian polycystic ovaries.