Lucimar Filot da Silva Brum

Evidence for the involvement of ionotropic glutamatergic receptors on the antinociceptive effect of (−)-linalool in mice

(-)-Linalool is a monoterpene alcohol which is present in the essential oils of several aromatic plants. Recent studies suggest that (-)-linalool has anti-inflammatory, antihyperalgesic and antinociceptive properties in different animal models. The present study investigated the contribution of glutamatergic system in the antinociception elicited by (-)-linalool in mice. Nociceptive response was characterized by the time that the animal spent licking the injected hind paw or biting the target organ following glutamate receptor agonist injections. (-)-Linalool administered by intraperitoneal (i.p., 10-200 mg/kg), oral (p.o., 5-100 mg/kg) or intrathecal (i.t., 0.1-3 microg/site) routes dose-dependently inhibited glutamate-induced nociception (20 micromol/paw, pH 7.4) with ID(50) values of 139.1 mg/kg; 34.6 mg/kg; and 0.9 microg/site, with inhibitions of 70+/-4; 72+/-7 and 74+/-8%, respectively. However, the intraplantar injection of (-)-linalool partially (49+/-9%) inhibited glutamate-induced nociception. Furthermore, (-)-linalool (200 mg/kg) given i.p. also reduced significantly the biting response caused by intrathecal injection of glutamate (30 microg/site), AMPA (25 ng/site), SP (135 ng/site), NMDA (25 ng/site) and kainate (23.5 ng/site), with inhibitions of 89+/-6%, 73+/-11%, 85+/-4%, 98+/-2% and 52+/-15%, respectively. However, (-)-linalool did not inhibit nociception induced by intrathecal injection of trans-ACPD (8.6 microg/site). Taken together, these results provide experimental evidences indicating that (-)-linalool produce marked antinociception against glutamate induced pain in mice, possible due mechanisms operated by ionotropic glutamate receptors, namely AMPA, NMDA and kainate.

Utilização de medicamentos por gestantes usuárias do Sistema Único de Saúde no município de Santa Rosa (RS, Brasil)

In order to ascertain the use of prescribed and unprescribed drugs among pregnant patients of the Unified Health System (SUS), a descriptive study comprised of a sample of pregnant women was carried out in the city of Santa Rosa, State of Rio Grande do Sul, Brazil. Data were collected by means of structured interviews and consultation of patient records of pregnant women in the prenatal period. The prevalence of drug use was 90%, corresponding to an average of 4.1 drugs per pregnant woman, of which 83.6% were prescribed and 16.4% were self-medicated. Of this total, 17.5% of the drugs were included in fetal risk category C. The use of drugs during pregnancy is frequent and the majority of the pregnant women used one or more prescribed and unprescribed drugs during pregnancy. These data suggest the need for preventive measures to promote rational drug use during pregnancy.

(−)-Linalool, a naturally occurring monoterpene compound, impairs memory acquisition in the object recognition task, inhibitory avoidance test and habituation to a novel environment in rats

It is known that (-)-linalool is a competitive antagonist of NMDA receptors, which play a key role in the learning and memory processes; however, only a few studies have reported a possible interference of (-)-linalool in memory. The purpose of this study was to investigate the (-)-linalool effects on acquisition of short- and long-term memories through the objects recognition task, inhibitory avoidance test and habituation to a novel environment. Furthermore, the open field test was used to investigate the interference of (-)-linalool in motivation, locomotion and exploration by animals. Wistar male adult rats received an intraperitoneal injection (i.p.) of saline (NaCl 0.9%), tween 5% or (-)-linalool (50 or 100 mg/kg) before training in the tasks; MK-801 (0.1 mg/kg), a glutamate antagonist, was used as positive control. Short-term (STM) and long-term (LTM) memories were tested 1.5 and 24 h after training, respectively, in the inhibitory avoidance and recognition objects. The results suggested that (-)-linalool (as 50- and 100-mg/kg doses) impaired LTM acquisition, but not STM acquisition, in the object recognition task. In the inhibitory avoidance test, animals receiving linalool (both doses) showed impairment in acquisition of both memories measured. In the open field test, the animals that received (-)-linalool showed no significant difference in the crossings and latency to start the locomotion in any of the doses tested, although (-)-linalool 100 mg/kg reduced rearing behavior. When re-exposed to open field 24 h after training, the rats that received (-)-linalool 100mg/kg showed no habituation. Taken together, these data suggested that (-)-linalool was able to impair the acquisition of memory in rats, which can be associated to (-)-linalool antagonist capacity as regards NMDA glutamatergic receptors, since other glutamate antagonists also seem to affect memory.

Effects of undernutrition on glutamatergic parameters in the cerebral cortex of young rats

Perinatal undernutrition impairs maturational events in the development of the brain, resulting in a variety of brain dysfunctions, which affect cognitive functions. This study investigated the effects of pre- and post-natal undernutrition (diet: 8% protein; control group: 25% protein) on some glutamatergic and behavioral parameters of 21-day-old rats. In the cerebral cortex, undernutrition reduced the Na-independent [(3)H]Glutamate binding in cellular membranes and [(3)H]Glutamate vesicular uptake, without affecting the [(3)H]Glutamate uptake by slices preparation. Behavioral parameters were affected, showing a strong amnesic effect both in the short- and long-term memory of inhibitory avoidance tasks, and a significant reduction in the number of crossings in an open field. The effects of perinatal undernutrition in 21-day-old rats, which alter some glutamatergic parameters may be related to the impairment of memory in certain behavioral tasks.

Habits of sun exposure and sunscreen use among university students from Teresina, Piauí State, Brazil

OBJETIVO:investigar habitos de exposicao solar e de fotoprotecao entre estudantes universitarios de Teresina-PI, Brasil.METODO:estudo transversal, com amostra representativa; foram investigadas associacoes entre caracteristicas demograficas e habitos de exposicao ao sol e de fotoprotecao.RESULTADOS:dos 398 universitarios entrevistados, 54,8% informaram expor-se ao sol menos de 2 horas diariamente; a maioria (66,8%) preferia horarios de menor intensidade de radiacao; 45,2% dos entrevistados referiram uso de filtro solar em seu dia-a-dia, e 82,4%, em exposicao voluntaria ao sol; o uso de camisetas foi outro recurso de fotoprotecao referido (44,2%) e 29,9% dos academicos receberam alguma orientacao profissional sobre fotoprotecao; as mulheres referiram mais frequentemente do que os homens o uso de fotoprotetores diariamente e em situacao de exposicao voluntaria (p<0,001).CONCLUSAO:a maioria dos universitarios referiu preferir horarios de baixa intensidade de radiacao, fazer uso de filtro solar e de outras medidas de fotoprotecao em exposicao voluntaria ao sol.

Hábitos de exposição ao sol e uso de fotoproteção entre estudantes universitários de Teresina, Piauí

OBJETIVO:investigar habitos de exposicao solar e de fotoprotecao entre estudantes universitarios de Teresina-PI, Brasil.METODO:estudo transversal, com amostra representativa; foram investigadas associacoes entre caracteristicas demograficas e habitos de exposicao ao sol e de fotoprotecao.RESULTADOS:dos 398 universitarios entrevistados, 54,8% informaram expor-se ao sol menos de 2 horas diariamente; a maioria (66,8%) preferia horarios de menor intensidade de radiacao; 45,2% dos entrevistados referiram uso de filtro solar em seu dia-a-dia, e 82,4%, em exposicao voluntaria ao sol; o uso de camisetas foi outro recurso de fotoprotecao referido (44,2%) e 29,9% dos academicos receberam alguma orientacao profissional sobre fotoprotecao; as mulheres referiram mais frequentemente do que os homens o uso de fotoprotetores diariamente e em situacao de exposicao voluntaria (p<0,001).CONCLUSAO:a maioria dos universitarios referiu preferir horarios de baixa intensidade de radiacao, fazer uso de filtro solar e de outras medidas de fotoprotecao em exposicao voluntaria ao sol.

Hábitos de exposición al sol y uso de fotoprotección entre estudiantes universitarios de Teresina, Piauí, Brasil

OBJETIVO:investigar habitos de exposicao solar e de fotoprotecao entre estudantes universitarios de Teresina-PI, Brasil.METODO:estudo transversal, com amostra representativa; foram investigadas associacoes entre caracteristicas demograficas e habitos de exposicao ao sol e de fotoprotecao.RESULTADOS:dos 398 universitarios entrevistados, 54,8% informaram expor-se ao sol menos de 2 horas diariamente; a maioria (66,8%) preferia horarios de menor intensidade de radiacao; 45,2% dos entrevistados referiram uso de filtro solar em seu dia-a-dia, e 82,4%, em exposicao voluntaria ao sol; o uso de camisetas foi outro recurso de fotoprotecao referido (44,2%) e 29,9% dos academicos receberam alguma orientacao profissional sobre fotoprotecao; as mulheres referiram mais frequentemente do que os homens o uso de fotoprotetores diariamente e em situacao de exposicao voluntaria (p<0,001).CONCLUSAO:a maioria dos universitarios referiu preferir horarios de baixa intensidade de radiacao, fazer uso de filtro solar e de outras medidas de fotoprotecao em exposicao voluntaria ao sol.