A PRELIMINARY INVESTIGATION OF THE EFFECTS OF AGING ON THE NERVE-CELLNUMBER IN THE MYENTERIC GANGLIA OF THE HUMAN COLON

We have examined the number of nerve cells present in the myenteric pl exus of the human large intestine using a nonhistochemical method (Gie msa) in laminar preparations of the muscularis externa in two groups o f subjects aged 20-35 and over 65 years. The collagen and elastic syst em related fibers in the myenteric ganglia were also qualitatively eva luated. The total number of neurons decreased in the old subjects by o ver 37%. The perikaryal area of most of the neurons in both the young and old subjects fell from 101 to 200 mu m(2). A ganglionic capsule wa s present and was thicker in the ganglia from the old subjects as were the septa within the ganglia. Both collagen and elastic system fibers were more numerous in the ganglia from the old subjects. We conclude that the decrease in neuron density with age is accompanied by an appa rent increase in the fibrous components of the myenteric ganglia.