Administration of
Piper guineense
fruit extract caused a dose - dependent mortality rate in rats. Doses of 200 mgkg
-1 intravenously, (i.v); 300 mgkg
-1 intraperitoneally, (i.p) and 3200 mgkg
-1 orally( p.o) produced 100% mortality rate - giving LD
50 of 85.1 mgkg
-1 i.v ; 224 mgkg i.p and 1122 mgkg
-1 p.o respectively. Piper extract significantly stimulated gastric ulceration, total gastric acidity and
in situ gastric acid secretion in rats. Piper-induced gastric ulceration appears to be similar to that induced by indomethacin (40 mgkg
-1 b.w). Atropine produced no effect on the stimulatory action of piper on gastric acid secretion. However, gastric acid secretion in the presence of histamine, and cimetidine appears to be augmented by piper extract (25 mgkg
-1 b.w). The results suggest that piper could stimulate gastric acid secretion (and probably gastric ulceration) via the H
2 - receptor potentiation.