Effect of calcium dobesilate on the functional capabilities of mesenteric lymphatics in the guinea pig.

The mean time between contractions of lymphangions of mesenteric lymph collectors in anaesthetised guinea pigs was 7.6 +/- 6.7s. The administration of saline had no significant effect on contraction times, nor did 50 mg/kg of calcium dobesilate in saline as a vehicle. However, at dose levels of 100 mg/kg and 200 mg/kg using saline as a vehicle the time between contractions significantly (P less than 0.001) increased to 11.4 +/- 14.8s and 12.9 +/- 23.3s, respectively. While neither the saline vehicle alone nor calcium dobesilate at any dose level influenced maximal collector diameters significantly, all dose levels of calcium dobesilate significantly (0.05 greater than P greater than 0.01) reduced minimal lumenal diameters to 30% of their maximum. The time that the lymphangion spends at its minimal diameter is an indication of the intensity of contraction. Saline alone had no significant effect, but calcium dobesilate at 50 mg/kg and 100 mg/kg significantly (0.05 greater than P greater than 0.01) increased this time from 0.9 +/- 1.2s to 1.9 +/- 1.9s and 2.0 +/- 1.6s, respectively. At 200 mg/kg of calcium dobesilate, there was a very significant increase (P less than 0.001) in minimal diameter times to 2.7 +/- 1.5s.