Tripeptidyl peptidase I activity in porcine lumbar spinal ganglia - a histochemical study.

Distribution of tripeptidyl peptidase I (TPPI) activity in the structures of porcine lumbar spinal ganglia (LSG) was studied by enzyme histochemistry on cryostat sections from all the ganglia using the substrate glycyl-L-prolyl-L-methionyl-5-chloro-1-anthraquinonyl hydrazide (GPM-CAH) and 4-nitrobenzaldehyde (NBA) as visualization factor. Light microscopic observations showed TPPI activity in almost all the LSG structures. The enzyme reaction in different cell types was compared semi-quantitatively. Strong reaction was observed in the small neurons, satellite ganglia cells and some nerve fibers. Weak reactivity was found in the large sensory somatic neurons, whereas moderate reaction for TPPI was determined in the middle sensory somatic neurons and some nerve fibers. Statistical analysis by one-way ANOVA showed no significance of difference (when p⟨0.05) for the number of TPPI positive neurons per mm2. The original data obtained by the enzyme histochemistry method give us a reason to presume that TPPI actively participates in the functions of all the neuronal structures in porcine LSG. According to our results, it could be suggested that TPPI activity is important for the functions of autonomic and somatic sensory neurons.

Histochemical Study of Heparin-positive Mast Cells in the Terminal Part of Porcine Ductus Choledochus and Papilla Duodeni Major.

The study presented in detail the localization and density of mast cells (MCs) in the intramural part of the common bile duct (CBD) and in the major duodenal papilla (MDP) of domestic swine. MCs' density (number/mm(2) ) in different layers of both of the duct and papilla was evaluated after toluidine blue staining. Their number was higher in the lamina propria mucosae than in the tunica muscularis of the studied structures. The localization of berberine-positive, (heparin containing) MCs and the ratio between them and toluidine blue-positive MCs with γ-ma metachromasia was also established. Ratios of heparin-containing MCs in comparison with all toluidine blue-positive MCs were found as follows: ductus choledochus - 32% in the subglandular connective tissue of lamina propria mucosae in the intramural part of the duct; m. sphincter ductus choledochus - 31% in the circular and 0.06% in the longitudinal muscle layer; subserosa - 59%; papilla duodeni major - 0.03% in the subepithelial connective tissue and 34% in the subglandular connective tissue of lamina propria mucosae, respectively. The established large difference in heparin-positive MCs in both the subepithelial and subglandular connective tissues of CBD and MDP, respectively, is an evidence for the existence of mucosal and connective tissue MCs.