Orofacial antinociceptive activity of codeine-associated geraniol in mice: a controlled triple-blind study

Abstract This is a nonclinical, controlled, and triple-blind study to investigate the effects of codeine-associated geraniol on the modulation of orofacial nociception and its potential central nervous system depressing effect in an animal model. The orofacial antinociceptive activity of geraniol in combination with codeine was assessed through the following tests: (i) formalin-induced pain, (ii) glutamate-induced pain, and (iii) capsaicin-induced pain. Six animals were equally distributed into six groups and received the following treatments, given intraperitoneally (i.p.) 30 minutes before the experiments: a) geraniol/codeine 50/30 mg/kg; b) geraniol/codeine 50/15 mg/kg; c) geraniol/codeine 50/7.5 mg/kg; d) geraniol 50 mg/kg; e) codeine 30 mg/kg (positive control); or f) 0.9% sodium chloride (negative control). We performed pain behavior analysis after the injection of formalin (20 µL, 20%), glutamate (20 µL, 25 µM), and capsaicin (20 µL, 2.5 µg) into the paranasal region. Rubbing time of the paranasal region by the hind or front paw was used as a parameter. In the neurogenic phase of the formalin test, the geraniol/codeine at 50/7.5 mg/kg was able to promote the maximum antinociceptive effect, reducing nociception by 71.9% (p < 0.0001). In the inflammatory phase of the formalin test, geraniol/codeine at 50/30 mg/kg significantly reduced orofacial nociception (p < 0.005). In the glutamate test, geraniol/codeine at 50/30 mg/kg reduced the rubbing time by 54.2% and reduced nociception in the capsaicin test by 66.7% (p < 0.005). Geraniol alone or in combination does not promote nonspecific depressing effects on the central nervous system. Based on our findings, we suggest the possible synergy between geraniol and codeine in the modulation of orofacial pain.

Variações na força muscular de membros superior e inferior nas diferentes fases do ciclo menstrual / Variations in strength muscle for upper and lower body in the different phases of the menstrual

Alguns componentes da aptidão física são marcadamente influenciados pelas fases do ciclo menstrual (CM). Portanto o objetivo foi verificar se existem diferenças nos níveis de força muscular dos membros superiores e inferiores em 19 mulheres eumenorréicas treinadas (26±5 anos; 61,1±6,1 kg; 165,3±5,6 cm), durante as diferentes fases do CM. A força foi avaliada pelo teste de 8RM, sendo um exercício para membro superior e outro para o membro inferior. Cada voluntária realizou seus testes em um único mês respeitando as fases dos seus respectivos CM. Foram aplicados quatro testes: no 1º dia da menstruação; na fase proliferativa; na fase ovulatória e na fase secretória. Para verificar as diferenças na carga em relação aos dias dos testes, foi realizada uma ANOVA de uma entrada com medidas repetidas para cada exercício. As variáveis que se mostraram significativas foram analisadas pelo teste post hoc de Tukey, considerando como nível de significância p<0,05. Os resultados apresentaram no exercício leg press 45º diferenças da 1ª fase para as demais fases do CM. Já a puxada no pulley não apresentou diferença em nenhuma das fases avaliadas. A amostra estudada sugere a influência do CM sobre a capacidade de produzir força em membros inferiores.

Some components of the physical fitness are influenced remarkably by the phases of the menstrual cycle (CM). Therefore the objective was to verify if differences exist in the levels of strength muscle of the upper and lower body in 19 women trained (26±5 years; 61.1±6.1 kg; 165.3±5.6 cm), during the different phases of the CM. The strength was evaluated by the test of 8RM, being an exercise for upper and lower body. Each volunteer accomplished their tests in a single month respecting the phases of their respective CM. Were applied four tests: in the 1st day of the period; in the phase proliferate; in the phase ovulation and in the secretors phase. To verify the differences in the load in relation to the days of the tests, an ANOVA of an entrance was accomplished with repeated measures for each exercise. The variables that were shown significant they were analyzed by the test post hoc of Tukey, considering as significance level p <0.05. The results already presented in the exercise leg press 45º differences of the 1st phase for the other phases of the CM. However do lat pull down didn’t present difference in none of the appraised phases. The studied sample suggests the influence of the CM on the capacity to produce force in inferior members.