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Aims: The objective was to evaluate the single exposure of general anesthetics with or without a surgical procedure at postnatal day 14 (P14) on nociceptive behavioral responses. Furthermore, we evaluated ectonucleotidase activities at P14 and P30. Place of Study: All experiments were performed at the Animal Experimentation Unit of Hospital de Clínicas de Porto Alegre. The Institutional Committee approved the experimental protocol f (GPPG-HCPA protocol No: 08149). Methodology: Fourteen-day-old male Wistar rats were divided into two experimental designs (ED): the 1st ED – control (C), isoflurane (ISO), isoflurane/surgery (ISO-SUR) and the 2nd ED – control (C), fentanyl/S(+)-ketamine (FK) and fentanyl/S(+)- ketamine/surgery (FK-SUR). Nociceptive responses were evaluated using the formalin and tail-flick tests, and the ectonucleotidase activities were evaluated by spinal cord synaptosome. All assessments were performed at P14 and P30. Results: The FK and FK-SUR groups displayed an increased latency at P30. For the ectonucleotidase activity analysis, the following results were observed: (a) in the 1st ED, the ISO group displayed a reduction in ATPase and ADPase, and both ISO and ISOSUR displayed a reduction in AMPase activity at P14; (b) in the 2nd ED, the FK group displayed an increase in AMPase activity at P14 and increased ATPase activity at P30, and both FK and FK-SUR exhibited an increase in AMPase activity at P30. Conclusion: Our results indicate that single administration of general anesthetics at P14 is able to promote changes in the nociceptive response in the intermediate-term, and in the ectonucleotidase activities in the short- and medium-terms.
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INTRODUÇÃO: Excesso de alimentação no início da vida pode modificar persistentemente consumo e peso corporal. Adoção de exercício físico é uma estratégia útil para evitar excessivo ganho de peso. OBJETIVO: Avaliar o crescimento corporal e a eficiência alimentar em ratos provenientes de ninhada reduzida no aleitamento. MÉTODOS: Ao terceiro dia de vida, ninhadas foram formadas com quatro (GN4) ou 10 animais (GN10), (n = 25). Ao desmame, ratos machos Wistar permaneceram em gaiolas individuais, e, aos 60 (± 2) dias foram subdivididos em sedentários (SED) e exercitados (NAT), formando quatro grupos: GN4SED, GN10SED, GN4-NAT e GN10NAT. Avaliou-se o peso, ganho de peso e taxa específica de ganho de peso, gordura epididimal, índices de massa corporal e Lee, consumo e eficiência alimentar, glicemia e lactemia. RESULTADOS: Aos 21 dias, o GN4 apresentava peso corporal 52 por cento acima do GN10 (P = 0,001). Contudo, aos 30 e 60 dias os pesos não diferiram. Ao final do período, GN10NAT demonstrou menor peso (356,82 ± 23,04) que GN10SED (409,28 ± 17,30). Mas GN4NAT possuía maior peso (417,85 ± 37,91) que GN4SED (413,69 ± 57,45) e GN10NAT. O GN4 exibiu elevada taxa de ganho de peso na lactação, mas, redução da mesma pós-desmame. Independente do tamanho da ninhada, a taxa de ganho de peso reduz com o aumento da idade. Ao final do período, glicemia, gordura epididimal total e relativa, e os índices de Lee e IMC não diferiram entre os grupos. Os valores de lactato antes e após o exercício condizem com esforço de intensidade moderada. Na periadolescência, GN4 apresentou menor ingestão de alimentos, mas sem diferenças na vida adulta. CONCLUSÃO: A redução da ninhada no aleitamento não alterou o peso corporal ou ingestão alimentar persistentemente. Entretanto, o protocolo de natação foi eficaz em reduzir o ganho de peso em animais controles, mas não naqueles de ninhada reduzida.
INTRODUCTION: Overfeeding in early life can persistently modify consumption and body weight. Adoption of exercise is one useful strategy to prevent excessive weight gain. OBJECTIVE: to assess body growth and feed efficiency in rats from reduced litters during lactation. METHODS: On day 3 of life, litters were formed with 4 (GN4) or 10 animals (GN10) (n = 25). When weaned, Wistar male rats were kept in individual cages and at day 60 (± 2) they were divided into sedentary (SED) and exercised (NAT), forming thus four groups: GN4SED; GN10SED; GN4NAT and GN10NAT. Assessment consisted of weight, weight gain and specific rate of weight gain, epididymal fat, Body Mass and Lee Indices, consumption and feed efficiency, blood glucose and lactemia. RESULTS: At day 21, GN4 had body weight 52 percent above GN10 (P = 0.001). However, at days 30 and 60, their weight was not different. At the end of the period, GN10NAT showed lower weight (356.82 ± 23.04) that GN10SED (409.28 ± 17.30), but GN4NAT was heavier (417.85 ± 37.91) than GN4SED (413.69 ± 57.45) and GN10NAT. GN4 presented higher rate of weight gain during lactation, but slower after weaning. Regardless of litter size, rate of weight gain reduces as age progresses. At the end of this period, blood glucose, total and relative epididymal fat, and Lee and BMI indices did not differ between groups. Pre and post-exercise lactate values are consistent with moderate effort. In periadolescence, GN4 showed lower food intake, but with no differences in adulthood. CONCLUSION: Reduced litter during lactation did not affect body weight or food intake persistently. However, the swimming protocol was effective in reducing weight gain in control animals, but not in animals from reduced litters.
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Animals , Rats , Anthropometry , Exercise , Infant , Rats, Wistar , SwimmingABSTRACT
Se evaluó la transmisión congénita de Trypanosoma cruzi en crías de ratas Wistar con infección aguda. Las ratas fueron inyectadas intraperitonealmente con 1,5x10(4) tripomastigotes metacíclicos de la cepa I/PAN/VE/00/PLANALTO linaje TcI. La parasitemia fue significativamente mayor (P<0,05) en las ratas infectadas preñadas (IP) que en las ratas infectadas vírgenes (IV). Las crías de las ratas IP a los 15, 30, 45 y 60 días de nacidas (dn) no mostraron tripanosomas circulantes. El ensayo ELISA reveló aumento progresivo de IgM anti-T. cruzi en el suero de 6 crías (24%) de las ratas IP entre los 15 y 60 dn. La IgG anti-T. cruzi disminuyó progresivamente en las crías de ratas IP y fueron negativos a los 60 dn. Cortes de corazón y músculo esquelético del 15% de las crías con 60 dn de las ratas IP mostraron antígeno de T. cruzi con PAP. ADN de T. cruzi fue detectado por PCR en el suero de 4 crías (16%) a los 60 dn de ratas IP. La presencia de anticuerpos IgM anti- T. cruzi y ADN del parásito en las crías de ratas con infección aguda, pueden ser considerados como un criterio de infección congénita en las crías sin parasitemia patente.
Congenital Trypanosoma cruzi transmission was evaluated in pups of Wistar rats with acute Chagas infection. The rats were injected intraperitoneally with 1.5 x 10(4) metacyclic tripomastigotes from the I/PAN/VE/00/PLANALTO strain TcI lineage. Parasitemia was significantly higher (P<0.05) in the pregnant infected rats (PI) than in the infected virgin rats (VI). The offspring of the PI rats at 15, 30, 45 and 60 days after birth (ab) did not show circulating trypanosomes. An ELISA test revealed progressive increase of anti-T. cruzi IgM in the serum of pups (24%) of the PI rats between 15 and 60 days. Anti-T. cruzi IgM decreased progressively in the PI pups and became negative at 60 ab. Heart and skeletal muscle sections of 15% of the pups of the PI rats at 60 ab showed T. cruzi antigen with PAP. T. cruzi DNA was detected through PRC in the serum of 4 pups (16%) of PI rats at 60 ab. Presence of anti-T. cruzi IgM and parasite DNA in the pups of rats with acute infection can be considered as a criterion of congenital infection in pups without evident parasitemia.
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Objective To determine whether exposure to electromagnetic radiation results in behavioral effects of rat pups.Methods Wistar rats,either male or female,were divided randomly into four groups respectively:control(CTR),100 seconds(S1),1000 seconds(S10)and 3000 seconds(S30),then each of them were exposed to electromagnetic radiation of 100 kV/m field amplitude of corresponding time.For the day of exposure till 2 months later.they were mated with the rats in the same group and their offspring were divided into four groups(F-GTB,F-S1,F-S10,F-S30)correspondingly.Behavioral changes occur in 2-month old and 6-month old rat pups were found between radiation groups and control,and in Y-maze test,beth male and female pups in F-S10 significantly learned fewer times than their control(total study times:male 14.6±3.9 vs 21.1±7.8,female13.4±3.0 vs 25.8±8.8;false times:male 3.5±2.4 vs 7.8±5.4,female 3.4±2.6 vs 11.0±7.2).In open field test,both maze,male pups in F-S1 and F-S30 learned more times than control in total study time(24.2±8.9 vs 14.1±5.2.30.7±12.4 vs 14.1±5.2).In step throush test and open field test,no significant differences were found between radiation groups and control.Conclusion There was significant genetic effect exposed to electromagnetic radiation of 100 kV/m,mainly manifested in rat pups in growth period but without long-term effect.