Ureshi M, Dainobu M, Sakai M
Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, 6-10 Senshu-kubota-machi, Akita 010-0874, Japan.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2002 Nov;188(10):767-79. doi: 10.1007/s00359-002-0364-0. Epub 2002 Nov 7.
This study addresses a potentially general basis of measuring time in a biological timer. Here, we examined the effects of biogenic amines on the time-fixed post-copulatory sexually refractory stage (ca. 1 h) which is defined as the time interval between spermatophore protrusion and the onset of a calling or a mating response in the reproductive cycle of the male cricket. For subcuticular injection of amines (0.15 ml, 10(-2) mol l(-1)), the interval of the refractory stage was shortened by octopamine, serotonin, 5-hydoxytryptophan and N-acetyl-serotonin but was unchanged by tryptophan, melatonin or 5-hydroxyindol-3-acetic acid. The effect of 5-hydoxytryptophan was most potent (maximum shortening, 38%) and long lasting (ca. 4.5 h) while other amines effected only the injected cycle. Injection of 5-hydoxytryptophan (180 nl, 10(-2) mol l(-1)) into the terminal abdominal ganglion also decreased the interval to a similar extent. Simultaneous injection of 5-hydoxytryptophan with the inhibitor of the serotonin synthesis enzyme reduced the 5-hydoxytryptophan effect suggesting that this effect results from synthesis of serotonin from 5-hydoxytryptophan. The protein synthesis inhibitor cycloheximide had no effect on the interval. These results suggest that the reproductive timer is regulated by serotonergic neurons in the terminal abdominal ganglion without protein synthesis during the interval of the time-fixed sexually refractory stage.
本研究探讨了生物定时器中测量时间的潜在通用基础。在此，我们研究了生物胺对交配后性不应期（约1小时）的影响，该不应期定义为雄性蟋蟀生殖周期中精包突出与鸣叫或交配反应开始之间的时间间隔。对于皮下注射胺类物质（0.15毫升，10⁻²摩尔/升），章鱼胺、血清素、5-羟色氨酸和N-乙酰血清素可缩短不应期的间隔，但色氨酸、褪黑素或5-羟吲哚-3-乙酸则无此作用。5-羟色氨酸的作用最为显著（最大缩短率为38%）且持续时间长（约4.5小时），而其他胺类物质仅影响注射后的周期。向腹部末端神经节注射5-羟色氨酸（180纳升，10⁻²摩尔/升）也能在类似程度上缩短间隔时间。同时注射5-羟色氨酸和血清素合成酶抑制剂可降低5-羟色氨酸的作用，这表明该作用是由5-羟色氨酸合成血清素所致。蛋白质合成抑制剂环己酰亚胺对间隔时间无影响。这些结果表明，在固定时间的性不应期内，生殖定时器由腹部末端神经节中的5-羟色胺能神经元调节，且无需蛋白质合成。
