Arechaga G, Sánchez B, Prieto I, Martínez J M, Alba F, Ramírez M
Departamento de Fisiologia, Facultad de Medicina, Universidad del País Vasco, Leioa, Vizcaya, España.
Rev Neurol. 1996 Dec;24(136):1503-6.
The aminopeptidases are considered to be enzymes which can regulate the activity of various neuropeptides. However, their precise function has not yet been fully determined.
With a view to studying the function of these enzymes at the cerebral level, the subcellular distribution of soluble leucine aminopeptidase from left and right cerebral hemisphere, in rats of different pre-natal and post-natal ages was determined as described in this paper.
The activity of soluble leucine aminopeptidase was determined fluorimetrically in the sub-cellular fractions obtained from the left and right cerebral hemispheres of rats of different pre-natal and post-natal ages: fetuses (of 19-21 days gestation), 1 week, 1, 5 and 24 months of age.
No differences were observed between the cerebral hemispheres at any of the ages studied. However, significant differences were seen in the evolutionary behaviour of the two hemispheres. At all ages, except 24 months, there were significant differences between the fractions. In the fetuses, most activity was seen at the level of the synaptosomal raw fraction and least in the microsomal. At 1-week-old, the highest levels were seen at a microsomal level. In rats of 1 and 5 months of age, the highest levels were detected at synaptosomal level. With regard to the evolution with age, in the homogenate, nuclear fraction, cytosol and mitochondrial fraction a similar profile was observed, with a decrease after birth and an increase at one month, being stable at the other ages. At a synaptosomal level the profile is similar, although the differences are much more marked, with a drastic decrease in activity at two years of age. By contrast, the microsomal fraction showed a very different evolutionary profile with an increase after birth, becoming stable at later ages.
The activity of soluble leucine aminopeptidase shows a heterogeneous subcellular distribution together with significant differences during cerebral development and ageing. The behaviour of this enzyme may reflect the functional state of its neuropeptide substrates.
氨肽酶被认为是能够调节各种神经肽活性的酶。然而，它们的确切功能尚未完全确定。
为了研究这些酶在大脑水平的功能，本文描述了测定不同产前和产后年龄大鼠左右脑半球可溶性亮氨酸氨肽酶的亚细胞分布情况。
采用荧光法测定不同产前和产后年龄大鼠（胎儿，妊娠19 - 21天；1周龄、1月龄、5月龄和24月龄）左右脑半球亚细胞组分中可溶性亮氨酸氨肽酶的活性。
在所研究的任何年龄组中，左右脑半球之间均未观察到差异。然而，两个半球的进化行为存在显著差异。在所有年龄组中，除24月龄外，各组分之间均存在显著差异。在胎儿中，大部分活性见于突触体粗提物水平，而微粒体中活性最低。在1周龄时，最高活性见于微粒体水平。在1月龄和5月龄大鼠中，最高活性见于突触体水平。关于随年龄的进化，在匀浆、细胞核组分、细胞质和线粒体组分中观察到类似的模式，出生后下降，1月龄时上升，在其他年龄稳定。在突触体水平，模式相似，尽管差异更为明显，2岁时活性急剧下降。相比之下，微粒体组分显示出非常不同的进化模式，出生后增加，在后期稳定。
可溶性亮氨酸氨肽酶的活性显示出亚细胞分布的异质性，以及在大脑发育和衰老过程中的显著差异。这种酶的行为可能反映了其神经肽底物的功能状态。
