Sen Shankhamala, Parishar Pooja, Pundir Arvind Singh, Reiner Anton, Iyengar Soumya
Division of Systems Neuroscience, National Brain Research Centre, Gurugram, Haryana, India.
Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, Tennessee, United States.
J Comp Neurol. 2019 Aug 1;527(11):1801-1836. doi: 10.1002/cne.24649. Epub 2019 Feb 19.
Birds of the family Corvidae which includes diverse species such as crows, rooks, ravens, magpies, jays, and jackdaws are known for their amazing abilities at problem-solving. Since the catecholaminergic system, especially the neurotransmitter dopamine, plays a role in cognition, we decided to study the distribution of tyrosine hydroxylase (TH), the rate-limiting enzyme in the synthesis of catecholamines in the brain of house crows (Corvus splendens). We also studied the expression of DARPP-32 (dopamine and cAMP-regulated phosphoprotein), which is expressed in dopaminoceptive neurons. Our results demonstrated that as in other avian species, the expression of both TH and DARPP-32 was highest in the house crow striatum. The caudolateral nidopallium (NCL, the avian analogue of the mammalian prefrontal cortex) could be differentiated from the surrounding pallial regions based on a larger number of TH-positive "baskets" of fibers around neurons in this region and greater intensity of DARPP-32 staining in the neuropil in this region. House crows also possessed distinct nuclei in their brains which corresponded to song control regions in other songbirds. Whereas immunoreactivity for TH was higher in the vocal control region Area X compared to the surrounding MSt (medial striatum) in house crows, staining in RA and HVC was not as prominent. Furthermore, the arcopallial song control regions RA (nucleus robustus arcopallialis) and AId (intermediate arcopallium) were strikingly negative for DARPP-32 staining, in contrast to the surrounding arcopallium. Patterns of immunoreactivity for TH and DARPP-32 in "limbic" areas such as the hippocampus, septum, and extended amygdala have also been described.
鸦科鸟类包括乌鸦、白嘴鸦、渡鸦、喜鹊、松鸦和寒鸦等多种物种，它们以惊人的解决问题的能力而闻名。由于儿茶酚胺能系统，尤其是神经递质多巴胺，在认知中发挥作用，我们决定研究酪氨酸羟化酶（TH）的分布，TH是家鸦（Corvus splendens）大脑中儿茶酚胺合成的限速酶。我们还研究了多巴胺和cAMP调节的磷蛋白（DARPP-32）的表达，该蛋白在多巴胺感受神经元中表达。我们的结果表明，与其他鸟类物种一样，TH和DARPP-32在家鸦纹状体中的表达最高。尾外侧巢皮质（NCL，相当于哺乳动物前额叶皮质的鸟类脑区）可以与周围的皮质区域区分开来，因为该区域神经元周围有大量TH阳性的纤维“篮”，且该区域神经毡中DARPP-32染色强度更高。家鸦的大脑中也有与其他鸣禽的鸣叫控制区域相对应的独特核团。在家鸦中，与周围的内侧纹状体（MSt）相比，发声控制区域X中TH的免疫反应性更高，而在RA和HVC中的染色则不那么明显。此外，与周围的弧皮质相比，弧皮质鸣叫控制区域RA（弧皮质粗壮核）和AId（中间弧皮质）的DARPP-32染色呈明显阴性。还描述了海马体、隔区和扩展杏仁核等“边缘”区域中TH和DARPP-32的免疫反应模式。
