Laboratorio de Neurofisología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Apdo. 04510 México, DF, México.
Chronobiol Int. 2010 Jan;27(1):34-51. doi: 10.3109/07420520903398526.
Previous studies suggested the retina could be a putative locus of daily crustacean hyperglycemic hormone (CHH) secretion, as it possesses its own metabolic machinery and is independent of the well-known CHH eyestalk locus responsible for the circadian secretion of this peptide. However, it has been proposed that hemolymph glucose and lactate concentrations play a dual role in the regulation of CHH in crayfish. To elucidate the temporal relationship between these two different CHH production loci and to examine their relationship with glucose regulation, we investigated the expression of CHH daily and circadian rhythms in the eyestalk and retina of crayfish using biochemical methods and time series analysis. We wanted to determine whether (1) putative retina and eyestalk CHH rhythmic expressions are correlated and if the oscillations of the two metabolic products of lactate and glucose in the blood due to CHH action on the target tissue correlate, and (2) retina CHH (RCHH) and the possible retinal substrate glycogen and its product glucose are temporally correlated. We found a negative correlation between daily and circadian changes of relative CHH abundance in the retina and eyestalk. This correlation and the cross-correlation values found between eyestalk CHH and hemolymph and glucose confirm that CHH produced by the X-organ sinus gland complex is under the previously proposed dual feedback control system over the 24 h time period. However, the presence of both glycogen and glucose in the retina, the cross-correlation values found between these parameters and hemolymph lactate and glucose, as well as RCHH and hemolymph and retina metabolic markers suggest RCHH is not under the same temporal metabolic control as eyestalk CHH. Nonetheless, their expression may be linked to common rhythms-generating processes.
先前的研究表明，视网膜可能是甲壳类动物每日血糖激素 (CHH) 分泌的假定部位，因为它具有自己的代谢机制，并且不受负责该肽昼夜分泌的著名 CHH 眼柄部位的影响。然而，有人提出，血淋巴葡萄糖和乳酸浓度在调节螯虾 CHH 方面发挥双重作用。为了阐明这两个不同的 CHH 产生部位之间的时间关系，并研究它们与葡萄糖调节的关系，我们使用生化方法和时间序列分析研究了螯虾眼柄和视网膜中 CHH 的日常和昼夜节律表达。我们想确定是否 (1) 假定的视网膜和眼柄 CHH 节律表达是否相关，以及由于 CHH 作用于靶组织导致的血液中两种代谢产物乳酸和葡萄糖的波动是否相关，以及 (2) 视网膜 CHH (RCHH) 和可能的视网膜基质糖原及其产物葡萄糖是否在时间上相关。我们发现视网膜和眼柄中相对 CHH 丰度的日常和昼夜变化之间存在负相关。这种相关性以及在眼柄 CHH 与血淋巴和葡萄糖之间发现的互相关值证实，X 器官窦腺复合体产生的 CHH 在 24 小时时间内受到先前提出的双反馈控制系统的控制。然而，视网膜中存在糖原和葡萄糖，这些参数与血淋巴乳酸和葡萄糖之间以及 RCHH 与血淋巴和视网膜代谢标志物之间发现的互相关值表明，RCHH 不受与眼柄 CHH 相同的时间代谢控制。尽管如此，它们的表达可能与共同的节律生成过程有关。
