Chapter 34 Fetal cortical transplants surviving in injured sensorimotor cortex of rats: cellular composition and function

Abstract

Publisher Summary This chapter discusses fetal cortical transplants surviving in the injured sensorimotor cortex of rats. The cellular composition of fetal cortical grafts surviving in injured sensorimotor cortex of adult rats is discussed. Fetal neocortical grafts surviving in cavities formed in the sensorimotor cortex of adult rats vary in volume and the degree of physical adherence to host brains. Generally, these grafts have a normal or decreased number of neurons, but their cytoarchitecture is usually abnormal. A reduction in the number of morphologically normal neurons is also observed in grafts histochemically reacted for nicotinamide adenine dinucleotide phosphate-oxidase (NADPH)-diaphorase (NADPH-d). The motor deficit produced by removing cortical grafts surviving in the injured sensorimotor cortex of neonatal rats is briefly discussed in the chapter. In view of the reported failure of fetal cortical grafts to ameliorate the motor impairments of cortically injured adult rats, it is observed whether grafts transplanted into newborn rats are functional. In an experiment described in the chapter, cavities were made in the right motor cortex of 2 day old rats. One week later a slab of embryonic cortex approximately 2 mm 2 was grafted into these cavities. Host subjects were allowed to mature for 6 weeks. At this time, they were trained to press two levers in alternation as fast as possible using their left forelimb to obtain food rewards.