The Development of Medial Geniculate Body in Man: Changes in the Cholinesterase (CHE) Activity During Fetal and Perinatal Life

Abstract

In the present study cholinesterase histochemi-cal (ChE) techniques have been used to demonstrate dif ferentiation and maturation of the medial geniculate body (MGB) in the human fetuses (ranging between 10.5 to 28 weeks) and infants (premature and three postnatal months). In the youngest specimens examined (10.5 to 15 weeks) moderate ChE activity was found in the neuropil of MGB. In the next developmental stage ChE activity is significantly increased with stronger reactivity in the pre-ripheral part of MGB. In the fetuses between 22 to 26 weeks of gestation peak ChE reactivity was observed in MGB. Reactivity is strong and homogenous. In the pre mature infant (28 weeks and older) ChE reactivity be comes inhomogenous and irregular with appearance of ChE positive bands in the moderately stained MGB ma trix. In addition. strongly ChE reactive cell bodies can be discerned. In 3-month-old infant brain we have found significant decrease of ChE reactivity in the neuropil of the MGB. In conclusion we can say that MGB shows very strong, transient ChE reactivity during second half of gestation. Since a great majority of ChE reactivity disap pears during later postnatal development, it is very likely that strong fetal activity is related to the histogenectic events and maturation of MGB.