Improvement of macromolecular clearance via lymph flow in hamster gingiva by topical warming and massage

The lymphatic system is very important for macromolecular clearance in vari ous tissues, especially in the gingiva. However, the kinetics of macromolec ular clearance via the lymph flow in the gingiva are poorly understood. The aim of this study was to investigate whether thermal or mechanical stimula tion affects macromolecular clearance via the lymph flow in the gingiva. Ca rbon black suspension was injected into the mandibular gingiva of anestheti zed hamsters and its drainage into cervical lymph nodes was examined. Clear ance of C-14-methylated bovine albumin and tritiated water from the gingiva and their drainage into submandibular lymph nodes and blood was quantified . The effect of topical warming or massage on clearance of C-14-methylated albumin from the gingiva during a 15 min period was examined. In addition, the influence of neurochemical antagonists on the stimulatory effect of top ical warming on albumin clearance was investigated. Submandibular lymph nod es were clearly delineated by carbon black 10 min after the injection. More radiolabeled albumin appeared in submandibular lymph nodes than in serum, while more tritiated water appeared in serum. Topical warming (45 degrees C . 2 min) and warming plus massage (with a silicon rubber brush, 20 s) decre ased the radiolabeled albumin in the gingiva 15 min after the injection. Th ere was less radiolabeled albumin in the gingiva after gingival warming plu s massage than after warming. Previous injection of HOE140 or propranolol i nto the gingiva diminished the stimulatory effect of topical warming on alb umin clearance. it was concluded that topical warming plus massage improves macromolecular clearance via the lymph How in hamster gingiva.