ABSTRACT
It is common observation that in aged people, the number of processes in long-axonal and equal-axonal neurons decreases. Quantitative ratio of these neurons changes, as well. While at mature age long-axonal/equal-axonal ratio is 3 : 1, at old age it makes 1 : 2. In dogs, unlike in human beings, the old age influences neither the number of processes, nor the quantitative ratio of the neurons mentioned.
Subject(s)
Jejunum/innervation , Myenteric Plexus/anatomy & histology , Adult , Age Factors , Aged , Animals , Dogs , Humans , Nerve Degeneration , Species SpecificityABSTRACT
A study was made of the morphological peculiarities of the varicose corpuscles revealed in man and animals at the terminal stages of ontogenesis along the peripheral nerve fibers. The properties of these varicose bodies were compared with the reactive varicose deformities experimentally observed under conditions of disturbed blood supply. Similar features of the two formations compared and the presence of transitional forms permit to regard the former ones as the reactive structures. However, more time and participation of the surrounding tissue is required for their formation.
Subject(s)
Aging , Hypoxia/pathology , Peripheral Nerves/anatomy & histology , Aged , Animals , Anura , Dogs , Humans , Intestine, Small/innervation , Microscopy, Phase-Contrast , Middle Aged , Peripheral Nerves/pathologyABSTRACT
The small intestine of the ageing human (15 cases from 70 to 88 years of age) and dogs (20 cases from 15 to 20 years of age) was treated by histological and neuro-histological methods. Vacuolic dystrophy of neurons and hyperplasia, thickening of their processes were found. Different formations up to 15 in number and from 20 to 60 mkm in size were revealed in the dog small intestine wall along the course of the nerve fibre. They were of pear-like, oval or round shape. Inside these formations sometimes there occur disfibration of neurofibrilles resulting in formation of structures which resemble incapsulated sensory apparatus. In the human small intestine the bodies and processes of neurons suffer most of all, while in the dog the nerve conductors do.
