Immunocytochemical Studies of Calbindin D-28k and Parvalbumin in the Sensory and motor Cortex of the Cat

Kim, Jong Joong; Chang, In Youb; Chung, Yoon Young; Yoon, Sang pil; Moon, Jeong Seok

Abstract

This study examined and compared the immunocytochemical distribution of the two calcium-binding proteins calbindin D-28k and parvalbumin in the sensory and motor cortex of the cat. In this experimental animal, calcium-binding protein calbindin D-28k immunoreactive neurons were mainly found many pyramidal cells distributed in layers 2 and 3 of the two cortical areas. Calbindin D-28k neuropil labeling was heaviest in layers 1 to 3. In contrast to parvalbumin, we found only minor differences in distribution, size and mor-phology of calbindin D-28k cell body or neuropil staining in the two cortical areas. Parvalbumin- immunoreactive cells were in all layers cortex except layer 1 and reached their peak density in the middle layers. The two cortical areas differed markedly in number, cell size and morphology of immunoreactive cells. Parvalbumin positive cells were more than twice as numerous in the two cortical areas compared to the calbindin D-28k positive cells. Calbindin D-28k and parvalbumin-immunoreactive somata were round, oval, spindle and polygonal in shape, and the positive neurons were unipolar, bipolar,multipolar and horizontal in shape. The diameters of the somata of the two positive neurons were 15~20 micrometer. Also, two positive dendrites were considerably densely arrayed in arborization.