Quantitative studies of argyrophilic APUD cells in airways and intestine: effects of hypothalamic injuries

Serotonin-containing epithelial cells in rat duodenum. I. Quantitative morphometric study of the distribution density

Serotonin (5HT)-containing epithelial cells in rat duodenum were studied quantitatively by three-dimensional morphometric analysis. Longitudinal sections covering the whole length of rat duodenum were stained by either 5HT immunohistochemistry or by glyoxylic acid fluorescent histochemistry. Three-dimensional values for positive cell density, namely the number of 5HT cells per unit volume of the epithelium, were obtained by stereological morphometry with the aid of a computer-assisted image analyzer. This analytical method provides an absolute value for the distribution density of 5HT-containing cells regardless of thickness of sections, or which of the two histochemical procedures is used. The mean number of such cells per unit volume was higher in the crypts than in the villi but varied little along the duodenum. The density of 5HT cells in a given duodenal region, however, varied greatly among individual animals. The villi of the 10 to 16-mm segment from the pylorus were identified as having the smallest individual variation and therefore as being the most suitable for statistical evaluation in future pharmacohistochemical investigations.

Quantitative study of pulmonary endocrine cells in anencephaly

Quantitative studies of pulmonary endocrine cells in 8 male autopsy cases of anencephaly were performed. The densities of pulmonary endocrine cells were expressed as the number of the total argyrophil cells/100 bronchiolar cell nuclei and as the number of the total argyrophil cells/mm bronchiole. The average values in the 8 anencephalic cases were 1.26 cells/100 nuclei and 3.56 cells/mm, and did not differ from the 1.28 cells/100 nuclei and 3.24 cells/mm in the control cases without malformation of the brain and without severe hyaline membrane disease of the lung. Furthermore, there was no significant difference in the densities of neuroepithelial bodies between the 2 groups. Immunostaining for calcitonin, bombesin, adrenocorticotropic hormone, chromogranin, and neuron-specific enolase also revealed no qualitative differences between them. It is concluded that defect and hypofunction of the hypothalamus-pituitary-adrenal axes associated with anencephaly do not have significant effects on the proliferation and differentiation of pulmonary endocrine cells in the fetus.