El Diazepam altera la ultraestructura del atrio fetal de ratón / Diazepam alters the ultrastructure of fetal atrium in rat

El diazepam (DZ) es un tranquilizante menor sintético, utilizado en pacientes con trastornos psicológicos y psiquiátricos. Es sedante, miorrelajante, anticonvulsionante y antipsicótico. El DZ atraviesa la barrera placentaria humana y la del ratón. Mujeres jóvenes que son adictas al fármaco, si se embarazan y continúan utilizándolo, sobre todo durante el primer trimestre, exponen a sus hijos a presentar alteraciones psicomotoras. El propósito de este trabajo fue investigar si el DZ administrado durante la gestación,induce alteraciones ultraestructurales del miocardio fetal de ratón. El grupo (DZ) de hembras gestantes deratón de la cepa CD-1 fue tratado con dosis únicas diarias de 1,0 mg/kg/pc/sc del día 6 al 17 y un grupo (C)que recibió solución salina. El día 18 las hembras de ambos grupos se anestesiaron, los fetos se perfundieron por vía intracardiaca con paraformaldehído al 1 % y glutaraldehido al 2,5 %, se les extrajo el corazón, se disecó el atrio, se fijó en OsO4 al 1 % y se incluyó en resina epóxica. Los cortes finos se contrastaron conacetato de uranilo y citrato de plomo y se observaron en un microscopio electrónico de transmisión. En los miocitos de los fetos del grupo DZ las sarcómeras del miocardio compacto tenían menor longitud que las del grupo C. Se observaron zonas con miofibrillas desorganizadas. El retículo sarcoplásmico de algunos miocitos presentaba cisternas distendidas y fragmentadas, mitocondrias alteradas y se observaron abundantes polirribosomas. Los cambios podrían deberse al efecto del DZ sobre la síntesis de actina y miosina pesada y sobre los organelos citoplásmicos, mediados por receptores benzodiazepínicos periféricos presentes en la membrana externa de las mitocondrias y asociados a canales de calcio dependientes de voltaje. Las alteraciones ultraestructurales del miocardio atrial de fetos de ratones expuestos in utero a DZ podrían tener efectos posnatales.

Diazepam (DZ) is a syntheticminor tranquilizer, used in patients with psychologicaland psychiatric disorders. It is a relaxing sedative,anticonvulsant and antipsychotic. DZ crosses thehuman placental barrier in mouse. Young women who are addicted to the drug, if they become pregnantand continue to use it, particularly during the firsttrimester, expose their children to psychomotor disorders. The purpose of this study was to investigate whether DZ administered during pregnancy induces ultrastructural alterations of fetal mouse myocardium.The group (DZ) of pregnant female mice of the CD-1strain was treated with a single daily dose of 1.0 mg/ kg / pc / sc of day 6 to 17 and a group (C) that received saline solution. On day 18 females of bothgroups were anesthetized, the fetuses were perfusedby intracardiac route with 1 % paraformaldehyde and 2.5 % glutaraldehyde, the heart was removed, theatrium was dissected, fixed in 1 % OsO4, it wasimmersed in epoxy resin. The fine sections werecontrasted with uranyl acetate and lead citrate and observed in a transmission electron microscope. Inthe myocytes of the fetuses of the DZ group, the sarcomers of the compact myocardium were shorter than those of the C group. Areas with disorganized myofibrils were observed. The sarcoplasmic reticulumof some myocytes had distended and fragmented 996cisterns, altered mitochondria, and abundant polyribosomes were observed. The changes may bedue to the effect of DZ on the synthesis of actin and heavy myosin and on cytoplasmic organelles mediatedby peripheral benzodiazepine receptors present onthe outer membrane of the mitochondria and associated with voltage-dependent calcium channels.Ultrastructural alterations of the atrial myocardium of fetuses of mice exposed to DZ in utero may have postnatal effects.

Ultrastructure of fetal mice hepatocytes exposed in utero to diazepam / Ultraestructura de hepatocitos fetales de ratón expuestos in utero a diazepam

Previous research has shown that fetal mice hepatic cells from females treated with diazepam (Valium) during pregnancy depict cytoplasmic and nuclear modifications when observed with photonic microscope. The purpose of this work is to investigate if diazepam administered subcutaneously (SC) to pregnant mice females induces ultraestructural alterations in the cytoplasmic organelles and nucleus to fetal hepatocytes. Transmission electron microscopy observations of fetal hepatocytes from pregnant females treated with a single daily dose of diazepam 2.7 mg/kg/bw/SC administered from 6th to 15th days of gestation revealed that they frequently presented disorganized and dilated rough endoplasmic reticulum cisterns, membranous elements, abundant Golgi complex and glycogen granules, around large vacuoles. The voluminous nucleus shows atypical distribution of chromatin. These alterations could modify the hepatocyte's physiology and probably persist after birth.

Estudios previos muestran que las células hepáticas de fetos de ratón, de hembras tratadas con diazepam (Valium) durante la gestación, presentan modificaciones citoplásmicas y nucleares que se pueden observar con el microscopio fotónico, por lo que el propósito de este trabajo es determinar si el diazepam administrado por vía subcutánea (SC) a hembras gestantes de ratón, induce alteraciones ultraestructurales de los organelos citoplásmicos y del núcleo de los hepatocitos fetales. En los fetos de ratón del grupo experimental de hembras gestantes, tratadas con dosis únicas diarias de 2,7 mg/kg de peso corporal administradas por vía SC del 6° al 15° día de la gestación, se observó con el microscopio electrónico de transmisión que los hepatocitos fetales presentaban con frecuencia retículo endoplásmico rugoso desorganizado, con cisternas dilatadas; había elementos membranosos y complejo de Golgi abundante, al igual que gránulos de glucógeno que rodeaban a grandes vacuolas. Los núcleos eran voluminosos, con la cromatina distribuida atípicamente. Estas alteraciones podrían modificar la fisiología de los hepatocitos y probablemente persistan después del nacimiento.

Morphological alterations in mouse placenta induced by diazepam / Alteraciones morfológicas inducidas en la placenta de ratón por diazepam

Diazepam (DZ) is a benzodiazepine that belongs to the group of minor tranquilizers with myo-relaxing and anticonvulsant properties. DZ and its metabolites cross the placental barrier in human, monkey, hamster, and mouse, and accumulate in the placenta. Our aim was to investigate, through histological techniques, and semifine sections if DZ induces morphological changes in the placenta. Twenty female mice of the ICR strain were distributed randomly in two groups. One group (DZ) was treated from days 6 to 17 of gestation with a single daily subcutaneous (sc) dose of DZ of 2.7 mg/kg/ (bw); the second, control group (C) was treated with saline solution. All females (10 DZ and 10 C) were killed by decapitation. Placentas were extracted and fixed in phosphates-buffered 10% formaldehyde, pH 7.3, dehydrated, and embedded in paraffin to obtain 3 µm thick sections or fixed in 2.5% glutaraldehyde, post-fixed in 1% OsO4, embedded in epoxy resin. Histological sections were stained with hematoxylin-eosin or Weigert´s iron hematoxylin. Semifine sections were stained with toluidine blue. All sections were observed under comparative light microscopy. The DZ-group showed thinned placental barrier with multiple vacuoles. Nuclei of trophoblast cells (TCs) and trophoblast giant cells (TGCs) presented heterochromatin in coarse granules, atypically distributed in the karyolymph and conspicuous nucleoli. The cytoplasm of the TGCs was vacuolated and chromatin had a similar appearance to that observed in TCs. The total area of the placental barrier was measured in µm2/µm2; the area in the DZ group was reduced as compared with the C group (P<0.001). Alterations of TGCs could be due to an interaction of DZ with peripheral type benzodiazepine receptors involved in progesterone biosynthesis. Administration of DZ in mice alters the placental barrier and TGCs which could affect their physiology and causes teratogenic effects on the ovary and testis involved in steroid hormones biosynthesis.

El diazepam (DZ) es una benzodiazepina que forma parte de los tranquilizantes menores con propiedades miorrelajantes y anticonvulsivantes. El DZ y sus metabolitos atraviesan la barrera placentaria en el humano, mono, hámster y ratón, y se acumula en ésta. Nuestro propósito fue investigar a través de técnicas histológicas y en cortes semifinos si el DZ induce cambios morfológicos en la placenta de ratón. Hembras de ratón de la cepa ICR se distribuyeron al azar en dos grupos. Un grupo (DZ) fue tratado del día 6 al 17 de la gestación con dosis únicas diarias subcutáneas (sc) de DZ de 2.7 mg/kg (pc); el segundo grupo control (C) se trató con solución salina. Todas las hembras (10 DZ y 10 C), se sacrificaron por decapitación. Se extrajeron las placentas y se fijaron en formaldehido al 10% amortiguado con fosfatos pH 7.3, se deshidrataron y se incluyeron en parafina para obtener cortes de 3 µm, o se fijaron en glutaraldehido al 2.5%, se posfijaron en OsO4 al 1% y se embebieron en resina epóxica. Los cortes histológicos se tiñeron con hematoxilina-eosina o con hematoxilina férrica de Weigert. Los cortes semifinos se tiñeron con azul de toluidina. Todos los cortes se observaron en un microscopio óptico de comparación. El grupo DZ presentó en la barrera placentaria múltiples vacuolas. Los núcleos de las células del trofoblasto y las células trofoblásticas gigantes (TGCs) presentaron heterocromatina en grumos gruesos, distribuidos atípicamente en la cariolinfa y nucléolos conspicuos. El citoplasma de las TGCs estaba vacuolizado y la cromatina tenía una apariencia similar a la observada en las células trofoblásticas. El área total de la barrera placentaria se midió en µm2/mm2; el área en el grupo DZ era reducida en comparación del grupo C (P<0.001). Las alteraciones de las células trofoblásticas y de las TGCs podrían deberse a la interacción del DZ con los receptores benzodiazepínicos de tipo periférico involucrados en la biosíntesis de progesterona. La administración de DZ en el ratón altera la barrera placentaria y las TGCs que podrían afectar su fisiología y causar efectos teratogénicos en el ovario y el testículo involucrados en la biosíntesis de las hormonas esteroides.

Amputation due to inadvertent intra-arterial diazepam injection

A case of limb gangrene secondary to accidental intra-arterial [I.A.] diazepam injection in an infant is described. Hazards of I.A. diazepam injection, the possible mechanisms leading to this injury, the preventive measures and the therapeutic modalities are discussed

Effects of diazepam on Mycobacterium bovis-induced infection in hamsters

The in utero exposure of hamsters to low doses of diazepam results in impaired host defense against Mycobacterium bovis during adulthood. Delayed developmental immunotoxicity, however, represents a specific situation that might not be general. The present experiment was undertaken to investigate the effects of diazepam on hamster resistance to M. bovis using adult animals. The effects of diazepam treatment on serum cortisol levels were also studied. Adult hamsters (N = 10 for each group) were treated with diazepam (E1 = 1.0, E2 = 2.0 or E3 = 3.0 mg kg-1 day-1 subcutaneously) or with control solution (C) for 30 days. Seven days after the beginning of the treatment, the animals received identical inoculum concentrations of M. bovis. Hamsters treated with the higher (2.0 and 3.0 mg kg-1 day-1) doses of diazepam exhibited: 1) increased granuloma areas in the liver (C = 1.81 + or - 1.39, E2 = 10.29 + or - 4.64 and E3 = 15.80 + or - 4.82) and lung (C = 0.54 + or - 0.55, E2 = 6.28 + or - 3.85 and E3 = 6.31 + + or - 3.56) and 2) increased scores of M. bovis colony-forming units isolated from liver (C = 2.0, E2 = 3.0 and E3 = 3.5), lung (C = 1.0, E2 = 3.0 and E3 = 3.5) and spleen (C = 1.0, E2 = 2.5 and E3 = 4.0). These effects were dose dependent, and were not detected or were less severe in animals treated with the lowest (1.0 mg/kg) dose of diazepam as well as in those of the control group. Furthermore, diazepam treatment (3.0 mg kg-1 day-1 for 30 days) increased (E3 = 71.32 + or - 2.99; N = 10) the serum levels of cortisol compared to control hamsters (C = 22.61 + or - 2.75; N = 10). The present data, that demonstrate an impaired defense against M. bovis in adult hamsters treated with diazepam, were tentatively explained on the basis of a direct and/or indirect action of diazepam on the cytokine network. The effects may be related to stimulation of peripheral benzodiazepine receptor binding sites (PBR) by macrophages and/or lymphocytes, or they may be mediated by PBR stimulation of the adrenals

Mutagenic activity of diazepan evaluated by in vivo cytogenetic tests

Background. Diazepam, one of the benzodiazepine group of tranquilizers, in used as an adjunctive drug for sedation and for relief of anxiety in the treatment of epilepsy. Suspicion has been aroused of a possible mutagenic and teratogenic effect of this drug, thus the potential for cancer development. Methods. To analyze the mutagenic effect of diazepam, the micronuclei and sister chromatid exchange (SCE) tests were performed by in vivo techniques in the bone marrow of Balb-C mice after intraperitoneal drug administration. Sixty mice, 30 males and 30 females, were classified as negative control (n=12), positive control (n=12), and three groups were treated with diazepam (n=36). All groups were matched by sex, and each mouse received a single intraperitoneal injection. Negative control group was injected with physiological saline, positive control group with mitomycin-C at a dose of 0.5 mg/kg of body weight. Treated groups received diazepam, one at 0.1, the other at 0.2, and the last, at 0.4 mg/kg. Results. The results showed a significant increase in the frequency of micronucleated polychromatic erythrocites at all doses tested for whole population in relation to negative control. The polychromatic/normochromatic erythrocyte ratio showed a significante decrease at doses of 0.1 and 0.4 mg/kg in relation to negative control, the male mice being those affected. Conclusions. It is concluded that diazepam showed mutagenic and genotoxic effects on bone marrow cells of mice and that it might represent a human health risk

Effects of gestational undernutrition, stress and diazepam treatment on spatial discrimination learning and retention in young rats.

Effects of prenatal undernutrition, stress and diazepam treatment on learning acquisition, and subsequent retention of a spatial discrimination task was assessed in the offsprings. Undernutrition of the dams was induced by restricting food intake to half, throughout the period of gestation, whereas footshock stress and diazepam (0.5 mg/kg, ip) treatment was given from day 13 to 20 of gestation, this being the critical period for neural development in this species. The pups born were subjected to spatial discrimination learning, and retention of the learning acquisition after an interval of one week, in a single unit black/white T-maze, at 8-9 weeks of age. The results indicate that prenatal undernutrition induces significant learning and retention deficits in the offspring, whereas the effect of prenatal stress was limited to only deficit in learning acquisition. Prenatally administered diazepam induced significant deficits in learning acquisition and subsequent retention of the discrimination task in pups culled from normally nourished dams. However, offsprings from diazepam administered undernourished dams exhibited less marked cognitive deficits, which may be attributable to the altered emotional reactivity of pups born to undernourished mothers. Prenatally administered diazepam also induced differential effects in stressed and non-stressed dam offsprings, though the effects were statistically insignificant. The results suggest that prenatal insults, in the form of undernourishment, stress and anxiolytic drugs, leave a lasting imprint on cognitive behaviour of the offspring. The final effect on this behaviour may be determined by the co-existence of these prenatal factors, particularly at a time when the foetus is vulnerable because of neural development and differentiation.

Physical and behavioral development in rats after late prenatal exposure to diazepam.

The effect of late prenatal exposure to diazepam (DZP) on physical and behavioral development of rat pups was investigated. Prenatal exposure to DZP (20 mg/kg, sc, in last week of pregnancy) did not alter litter size and no gross malformations were noted at birth. Body weight at birth and subsequent weight gain was significantly less in these animals. The development of reflexes and neuromuscular maturation was normal. Open field locomotor activity and rearing scores were significantly decreased. Test of social play in juvenile rats revealed normal pattern of sexual dimorphism with increased masculinized behavior. Acquisition and retention of passive avoidance task was not affected by DZP exposure, however, retention of brightness discrimination task was significantly decreased. The hypnotic effect of a challenge dose of DZP and convulsive effect of pentylene tetrazole remained unaltered. Open field activity test in adult animals revealed increased ambulation. Probe dose of amphetamine in these animals caused paradoxical decrease in activity. It is concluded that exposure to high dose of DZP during late prenatal period may not manifest in physical or neuromuscular impairment during early development period, except for weight loss, however, it may have long term effects on behavior becoming manifest in adolescence and at maturity.