Ultrastructural Changes in the Canine Ileal Mucosal Cell After Mesenteric Arterial Occlusion

Abstract

Laparotomy was performed on seven healthy male mongrel dogs. The control sample of ileal mucosa was taken and a clamp applied to the superior mesenteric artery. Sections of ileal mucosa were obtained after clamping for electron microscopic study. By ten minutes after clamping, there was an accumulation of fluid infranuclearly with bulging of plasma and basement membranes. The mitochondria were somewhat swollen, however, lysosomes, rough endoplasmic reticulum, and nuclei were normal. Thirty minutes after clamping, the terminal web was clear with loss of protein normally present. Mitochondria were swollen with destruction of cristae, the rough endoplasmic reticula were dilated, and the outer membrane of the nucleus was separated. The lysosomes still appeared normal. Most striking was the large size of the intercellular spaces infranuclearly with fracturing of the intercellular membrane and lifting of the cell.