Mechanical properties of isolated human oesophageal submucosal veins.

The mechanical properties of isolated human oesophageal submucosal veins were investigated. The veins were without tone or spontaneous activity and possessed a high compliance, tolerating a stretch of several hundred per cent of the length at which the vessels were first able to contract with only minor increases in passive tension. The veins were capable of producing active tension when the length exceeded 30% of L0 (the length at which maximum wall tension (T0) was developed when activated by 124 mM K(+)-solution). The veins from the oesophageal body (OB) had a higher L0 than the veins from the gastrooesophageal junction (GOJ) (1180 microns vs 820 microns) and T0 was correspondingly higher (1.1 mN/mm vs. 0.6 mN/mm). However, there was no significant difference in the calculated effective transmural pressure (P) at the two locations. Noradrenaline induced contractions in all preparations tested with a maximum response equivalent to the tension achieved after stimulation with 124 mM K(+)-solution, pD2 values for noradrenaline in vessels from the oesophageal body and the gastroesophageal junction were 7.03 +/- 0.28 (mean +/- SEM) and 7.15 +/- 0.20, respectively. The present model seems suitable for future studies of human oesophageal submucosal veins from the oesophageal body and the gastrooesophageal junction.