Barbehenn E K, Noelker D M, Chader G J, Passonneau J V
Exp Eye Res. 1985 May;40(5):675-86. doi: 10.1016/0014-4835(85)90137-x.
Eight layers of frog retina were analyzed for ATP, P-creatine, ATP + ADP, and AMP under conditions of dark, 2 sec, 2 min, and in the case of AMP, 2 hr of light adaptation. Samples of each layer, usually ranging between 5 and 50 ng, were dissected from lyophilized frozen sections. After brief light exposure, ATP dropped while ADP rose sharply in the pigment epithelium, outer segments, and inner segments; ADP was too low to be measured accurately in the inner retina. The profile of ATP, P-creatine, and ATP + ADP concentrations showed peaks in the inner nuclear and ganglion layers. AMP, by contrast, was highest in the two plexiform layers. Levels in the inner retina dropped after only 2 sec of light but rose after 2 hr to levels that were higher than dark values in all retinal layers. AMP was often characterized by a non-uniform distribution: adjacent areas of a layer agreed very closely in value to each other but could vary several-fold from a different section of the same frog or from another frog exposed to the same conditions. This distribution produced clusters of values, particularly prominent in dark-adapted animals, something not observed with the other metabolites measured. The peaks of AMP in the plexiform layers suggest that AMP may be a by-product of dopamine-stimulated adenylate cyclase which also has peaks in these same layers.
在黑暗、2秒、2分钟的条件下，以及在光适应2小时（仅针对AMP）的情况下，对青蛙视网膜的八层结构进行了ATP、磷酸肌酸、ATP + ADP和AMP的分析。每层样本通常在5至50纳克之间，从冻干的冰冻切片中解剖获取。短暂光照后，色素上皮、外段和内段中的ATP下降，而ADP急剧上升；内视网膜中的ADP过低，无法准确测量。ATP、磷酸肌酸和ATP + ADP浓度曲线在内核层和神经节层出现峰值。相比之下，AMP在两个神经纤维层中含量最高。内视网膜中的水平在光照仅2秒后下降，但在2小时后上升，高于所有视网膜层的黑暗值。AMP的分布通常不均匀：一层中的相邻区域彼此的值非常接近，但同一青蛙的不同切片或暴露于相同条件下的另一只青蛙的不同切片之间可能相差几倍。这种分布产生了值的聚类，在暗适应动物中尤为明显，这是所测量的其他代谢物未观察到的现象。神经纤维层中AMP的峰值表明，AMP可能是多巴胺刺激的腺苷酸环化酶的副产物，而多巴胺刺激的腺苷酸环化酶在这些相同层中也有峰值。
