Pérez J, Hoyer D
SANDOZ Pharma Ltd., Basel, Switzerland.
Neuroscience. 1995 Jan;64(1):241-53. doi: 10.1016/0306-4522(94)00364-b.
In situ hybridization histochemistry was used to study the distribution and possible co-expression of the messenger RNA of the somatostatin receptor subtypes SSTR-4 and SSTR-3 in rat brain. Our results demonstrate that SSTR-3 messenger RNA is widely expressed within the rat brain, while expression of SSTR-4 messenger RNA is restricted to the telencephalon, diencephalon and granular layer of the cerebellum. It is also shown that single neurons can co-express both SSTR-4 and SSTR-3 receptor messenger RNAs. The highest density of SSTR-4 messenger RNA was found in the pyramidal cell layer of the hippocampus, especially in the CA1 and CA2 areas, anterior olfactory nuclei, amygdala, and in layers IV and VI of the cerebral cortex. SSTR-3 messenger RNA displayed a homogeneous distribution in the cerebral cortex and was expressed in the olfactory bulb, pyramidal cells of the hippocampus, granular cell layer of the dentate gyrus, motor and sensory metencephalic nuclei, and the granular and Purkinje cell layers of the cerebellum. Whether SSTR-3 and SSTR-4 messenger RNA can be expressed by the same cell was assessed by the simultaneous use of digoxigenin (SSTR-3)- and isotopic (SSTR-4)-labelled oligoprobes. Co-expression of SSTR-3 and SSTR-4 messenger RNAs was found in neurons of the CA1 and CA2 regions of the hippocampus, in the subiculum and in layer IV of the cerebral cortex. The expression of two receptor subtypes of the same neurotransmitter in a single cell, if confirmed functionally, raises questions about the consequences of the simultaneous activation of these different receptors.
采用原位杂交组织化学方法研究生长抑素受体亚型SSTR - 4和SSTR - 3的信使核糖核酸（mRNA）在大鼠脑内的分布及可能的共表达情况。我们的研究结果表明，SSTR - 3 mRNA在大鼠脑内广泛表达，而SSTR - 4 mRNA的表达局限于端脑、间脑和小脑颗粒层。研究还表明，单个神经元可同时表达SSTR - 4和SSTR - 3受体的mRNA。在海马锥体细胞层，尤其是CA1和CA2区、前嗅核、杏仁核以及大脑皮层IV层和VI层发现SSTR - 4 mRNA的密度最高。SSTR - 3 mRNA在大脑皮层呈均匀分布，在嗅球、海马锥体细胞、齿状回颗粒细胞层、脑桥运动和感觉核以及小脑颗粒层和浦肯野细胞层均有表达。通过同时使用地高辛配基（SSTR - 3）标记和同位素（SSTR - 4）标记的寡核苷酸探针，评估SSTR - 3和SSTR - 4 mRNA是否能由同一细胞表达。在海马CA1和CA2区的神经元、海马下托以及大脑皮层IV层发现了SSTR - 3和SSTR - 4 mRNA的共表达。同一神经递质的两种受体亚型在单个细胞中的表达，若经功能证实，会引发关于同时激活这些不同受体后果的疑问。
