RESUMO
This study investigated the effects of maternal separation on the feeding behavior of rats. A maternal separation model was used on postnatal day 1 (PND1), forming the following groups: in the maternal separation (MS) group, pups were separated from their mothers each day from PND1 to PND14, whereas in the control (C) group pups were kept with their mothers. Subgroups were formed to study the effects of light and darkness: control with dark and light exposure, female and male (CF and CM), and maternal separation with dark and light exposure, female and male (SDF, SDM, SLF and SLM). Female rats had higher caloric intake relative to body weight compared with male controls in the dark period only (CF=23.3±0.5 v. CM=18.2±0.7, P<0.001). Macronutrient feeding preferences were observed, with male rats exhibiting higher caloric intake from a protein diet as compared with female rats (CF=4.1±0.7, n=8 v. CM=7.0±0.5, n=8, P<0.05) and satiety development was not interrupted. Female rats had a higher adrenal weight as compared with male rats independently of experimental groups and exhibited a higher concentration of serum triglycerides (n=8, P<0.001). The study indicates possible phenotypic adjustments in the structure of feeding behavior promoted by maternal separation, especially in the dark cycle. The dissociation between the mother's presence and milk intake probably induces adjustments in feeding behavior during adulthood.
Assuntos
Preferências Alimentares/fisiologia , Preferências Alimentares/psicologia , Privação Materna , Saciação/fisiologia , Animais , Animais Recém-Nascidos , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Feminino , Masculino , Gravidez , Ratos , Ratos WistarRESUMO
Here we analyze the outcomes of unlimited access to a low-energy (LE) diet in dams and their offspring. At 3 weeks' gestation, pregnant Wistar rats were divided into two groups: (1) the control group received a normoenergetic diet; and (2) the experimental group received the LE diet. In dams, lactation outcomes, food intake, body weight, plasma IGF-1, prealbumin, transferrin and retinol-binding protein levels were evaluated; in offspring, biometric and biochemical parameters and food intake were evaluated. No differences were observed during pregnancy. However, after lactation, dams that received the LE diet demonstrated significant reductions in body weight (P<0.05), plasma IGF-1 (P=0.01), prealbumin and visceral fat (P<0.001). Pups born to dams that received the LE diet demonstrated reduced body length and weight at weaning (P<0.001) and were lighter than the control animals at the end of the experimental period. Pups also demonstrated reduced plasma, low-density lipoprotein (P=0.04), triglycerides (P=0.002) and glucose levels (P<0.05), and differences were noted in visceral fat. These results indicate that feeding dams with LE diet during the reproductive period induces acute malnutrition and impairs the growth and development of offspring, as well as certain metabolic parameters.
Assuntos
Fenômenos Fisiológicos da Nutrição Pré-Natal , Animais , Peso Corporal , Ingestão de Alimentos , Metabolismo Energético , Feminino , Desenvolvimento Fetal , Desnutrição/etiologia , Estado Nutricional , Valor Nutritivo , Gravidez , Ratos WistarRESUMO
The effect of treatment with naloxone early in life on pain responsiveness was studied in Wistar rats. Litters of six rats were divided equally into groups of 3 pups receiving daily naloxone (50 mg/kg, sc) and 3 pups receiving saline from the 3rd to 18th day of life. On days 30, 50, 70 and 90, one group of animals previously injected during suckling with naloxone (N = 21) and another with saline (N = 21) were submitted to the hot-plate test to measure the latency to paw licking. Other groups of rats also treated during suckling with naloxone (N = 13) and saline (N = 14) were assessed for the antinociceptive effect of morphine (10 mg/kg,sc). The naloxone group displayed a lower latency than the saline group in all test sessions and a diminished analgesic response to morphine. The results indicate that the use of naloxone (an antagonist opioid) during suckling, the brain growth spurt period, facilitates a long-lasting increased pain responsiveness and alters antialgesic mechanisms. In this respect, the opioid and non-opioid effects of naloxone on the ontogeny of neural systems should be taken into account.
Assuntos
Hiperalgesia/fisiopatologia , Naloxona/farmacologia , Animais , Animais Recém-Nascidos , Animais Lactentes , Hiperalgesia/induzido quimicamente , Masculino , Morfina/farmacologia , Nociceptores/efeitos dos fármacos , Ratos , Tempo de Reação/efeitos dos fármacosRESUMO
The aim of the present research was to standardize the indirect immunofluorescence reaction for Endemic Pemphigus Foliaceus (Fogo Selvagem). We found that fresh human skin was the ideal substrate and could proceed from foreskin, head, neck, or anterior abdominal wall. PBS pre-washing of the skin preceding the incubation with the serum should be avoided since the antigenicity might be diminished. TAS-calcium pre-serves the Pemphigus antigenic properties of the skin and shall be preferred as the diluent for the sera. Albumin-coated slides are useful because they increase the adherence of the skin sections. The conjugate appropriate dilution is convenientely determined by the radial immunodiffusion test (Ouchterlony method). So far as the correlation between the antibody titer and the clinical activity is concerned, we concluded that a titer of 160 or more was of bad prognosis, since it was associated with the generalized form of the disease or with cases of the localized form refractory to the usual therapy. Nevertheless, this assumption needs confirmation by further studies involving an appropriate clinical approach.