RESUMO
INTRODUCTION: Designs for determining nociceptive response in rodents are of great use in neurology and experimental neuroscience. Immersing mice's tails in warm water is one of the most widely used procedures to evaluate this response; however, a wide range of temperatures are used in different studies. Knowing the temperature that produces a powerful nociceptive response in the tail of BALB/c mice is extremely useful. METHODS: Eight 2-month-old male BALB/c mice were used. A 14-cm high beaker was filled with water up to 13cm. The animals' tails were immersed in the container with a starting temperature of 36°C. The water temperature was raised in 1°C increments until we identified the temperatures that produced nociceptive responses. That response was determined by counting the time taken before the mouse shook its tail to remove it from the water. RESULTS: Six of the 8 mice began shaking their tails at the temperature of 51°C. All animals removed their tails from the water at the temperatures of 54°C, 55°C, and 56°C, taking a mean time of 8.54, 7.99, and 5.33seconds, respectively. ANOVA applied to the response times for each of the 3 temperatures indicated revealed a value of F=2.8 (P=.123). CONCLUSIONS: The response time was statistically similar for the temperatures of 54°C, 55°C, and 56°C; however, the data were less dispersed for the latter temperature.
Assuntos
Nociceptividade , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tempo de Reação , TemperaturaRESUMO
INTRODUCTION: Designs for determining nociceptive response in rodents are of great use in neurology and experimental neuroscience. Immersing mice's tails in warm water is one of the most widely used procedures to evaluate this response; however, a wide range of temperatures are used in different studies. Knowing the temperature that produces a powerful nociceptive response in the tail of BALB/c mice is extremely useful. METHODS: Eight 2-month-old male BALB/c mice were used. A 14-cm high beaker was filled with water up to 13 cm. The animals' tails were immersed in the container with a starting temperature of 36°C. The water temperature was raised in 1°C increments until we identified the temperatures that produced nociceptive responses. That response was determined by counting the time taken before the mouse shook its tail to remove it from the water. RESULTS: Six of the 8 mice began shaking their tails at the temperature of 51°C. All animals removed their tails from the water at the temperatures of 54°C, 55°C, and 56°C, taking a mean time of 8.54, 7.99, and 5.33seconds, respectively. ANOVA applied to the response times for each of the 3 temperatures indicated revealed a value of F=2.8 (P=.123). CONCLUSIONS: The response time was statistically similar for the temperatures of 54°C, 55°C, and 56°C; however, the data were less dispersed for the latter temperature.
RESUMO
Introducción: Los diseños para determinar la respuesta nociceptiva en roedores son de gran utilidad en neurología y en neurociencias experimentales. El paradigma de inmersión de la cola de ratón en agua temperada es uno de los más empleados para evaluar dicha respuesta; sin embargo, existe amplia variación en la temperatura utilizada en las diversas investigaciones. Resulta sumamente útil determinar la temperatura que produce una mejor respuesta nociceptiva sobre la cola de ratones de la cepa Balb/c.MétodosSe emplearon 8 ratones machos Balb/c de 2 meses de edad. Un beaker de 14 cm de alto se llenó de agua hasta 13 cm. Partiendo desde los 36 °C se empezó a sumergir la cola del animal dentro del recipiente. Se comenzó a elevar en 1 °C el agua hasta encontrar las temperaturas que produzcan las respuestas nociceptivas. Dicha respuesta se determinó contabilizando el tiempo que el ratón tardó en sacudir su cola retirándola del agua.ResultadosLos ratones empezaron a sacudir su cola a los 51 °C (6 de los 8 roedores). El total de la muestra retiró su cola del agua a los 54, 55 y 56 °C en el tiempo promedio de 8,54, 7,99 y 5,33 s, respectivamente. Al aplicar ANOVA a los tiempos de las 3 temperaturas señaladas se obtuvo el valor F = 2,8 y p = 0,123.ConclusionesEl tiempo de respuesta fue similar estadísticamente ante las temperaturas de 54, 55 y 56 °C; sin embargo se encontró menor dispersión de los datos ante esta última. (AU)
Introduction: Designs for determining nociceptive response in rodents are of great use in neurology and experimental neuroscience. Immersing mice's tails in warm water is one of the most widely used procedures to evaluate this response; however, a wide range of temperatures are used in different studies. Knowing the temperature that produces a powerful nociceptive response in the tail of BALB/c mice is extremely useful.MethodsEight 2-month-old male BALB/c mice were used. A 14-cm high beaker was filled with water up to 13 cm. The animals tails were immersed in the container with a starting temperature of 36 °C. The water temperature was raised in 1 °C increments until we identified the temperatures that produced nociceptive responses. That response was determined by counting the time taken before the mouse shook its tail to remove it from the water.ResultsSix of the 8 mice began shaking their tails at the temperature of 51 °C. All animals removed their tails from the water at the temperatures of 54 °C, 55 °C, and 56 °C, taking a mean time of 8.54, 7.99, and 5.33 seconds, respectively. ANOVA applied to the response times for each of the 3 temperatures indicated revealed a value of F=2.8 (P=.123).ConclusionsThe response time was statistically similar for the temperatures of 54 °C, 55 °C, and 56 °C; however, the data were less dispersed for the latter temperature. (AU)