Jarriault David, Barrozo Romina B, de Carvalho Pinto Carlos J, Greiner Birgit, Dufour Marie-Cécile, Masante-Roca Ingwild, Gramsbergen Jan B, Anton Sylvia, Gadenne Christophe
INRA, UMR 1272 Physiologie de l'Insecte: Signalisation et Communication, Versailles, France.
Horm Behav. 2009 Jun;56(1):185-91. doi: 10.1016/j.yhbeh.2009.04.005. Epub 2009 May 3.
Male moths use sex pheromones to find their mating partners. In the moth, Agrotis ipsilon, the behavioral response and the neuron sensitivity within the primary olfactory centre, the antennal lobe (AL), to sex pheromone increase with age and juvenile hormone (JH) biosynthesis. By manipulating the JH level, we previously showed that JH controls this age-dependent neuronal plasticity, and that its effects are slow (within 2 days). We hypothesized that the hormonal effect might be indirect, and one neuromodulator candidate, which might serve as a mediator, is octopamine (OA). Here, we studied the effects of OA and an OA receptor antagonist, mianserin, on behavioral and AL neuron responses of mature and immature males during stimulation with sex pheromone. Our results indicate that, although OA injections enhanced the behavioral pheromone response in mature males, OA had no significant effect on behavior in immature males. However, mianserin injections decreased the behavioral response in mature males. AL neuron sensitivity increased after OA treatment in immature males, and decreased after mianserin treatment in mature males. Determination of OA levels in ALs of immature and mature males did not reveal any difference. To study the possible interactive effects of JH and OA, the behavioral pheromone response was analyzed in JH-deprived mature males injected with OA, and in immature males injected with fenoxycarb, a JH agonist, and mianserin. Results show that both JH and OA are necessary to elicit a behavioral response of A. ipsilon males to sex pheromone.
雄性蛾类利用性信息素来寻找配偶。在小地老虎蛾中，初级嗅觉中枢触角叶（AL）内对性信息素的行为反应和神经元敏感性会随着年龄和保幼激素（JH）生物合成而增加。通过操纵JH水平，我们先前表明JH控制这种年龄依赖性的神经元可塑性，并且其作用缓慢（在2天内）。我们推测激素作用可能是间接的，一种可能作为介导物的神经调质候选物是章鱼胺（OA）。在这里，我们研究了OA和一种OA受体拮抗剂米安色林对成熟和未成熟雄性在性信息素刺激期间的行为和AL神经元反应的影响。我们的结果表明，虽然注射OA增强了成熟雄性对性信息素的行为反应，但OA对未成熟雄性的行为没有显著影响。然而，注射米安色林降低了成熟雄性的行为反应。未成熟雄性在OA处理后AL神经元敏感性增加，成熟雄性在米安色林处理后AL神经元敏感性降低。对未成熟和成熟雄性AL中OA水平的测定未发现任何差异。为了研究JH和OA可能的相互作用，对注射了OA的JH缺乏成熟雄性以及注射了JH激动剂苯氧威和米安色林的未成熟雄性的性信息素行为反应进行了分析。结果表明，JH和OA都是引发小地老虎雄性对性信息素行为反应所必需的。
