alloin and aloe-emodin-anthrone

Hypotensive effects of aloeemodin, aloin A, elgonica dimer A and bisbenzopyran from Aloe barbadensis have been studied. Aloeemodin has emerged as a potent hypotensive agent in current pharmacological investigations and caused 26 %, 52 %, and 79 % falls in mean arterial blood pressure at the corresponding doses of 0.5, 1, and 3 mg/kg in rats. The paper also describes the absolute configuration of elgonica dimer A (1).

Topics: Aloe; Animals; Anthraquinones; Antihypertensive Agents; Blood Pressure; Dose-Response Relationship, Drug; Emodin; Glucosides; Hypertension; Magnetic Resonance Spectroscopy; Phytotherapy; Plant Leaves; Plant Preparations; Plant Roots; Rats

Aloe-emodin-9-anthrone(AE-anthrone), produced from barbaloin in the rat large intestine, caused not only an increase in the intestinal water content but also stimulated mucus secretion. This might play an important role in the occurrence of diarrhea. It was demonstrated that the amount of AE-anthrone produced in the rat large intestine(maximal amount: 568 micrograms/rat at 4 h after injection) was enough to cause both of these effects, which were observed following intracecal administration of barbaloin (31.1 mg/kg). These results together with our previous data, which showed a relationship between increase in the intestinal water content and the stimulation of peristalsis, confirm that AE-anthrone is the principal agent responsible for the cathartic effect of barbaloin. We also propose that the increase in water content is a more important factor than stimulation of peristalsis in the induction of diarrhea by barbaloin.

Topics: Aloe; Animals; Anthracenes; Anthraquinones; Body Water; Cathartics; Chromatography, Thin Layer; Densitometry; Emodin; Feces; Intestinal Mucosa; Male; Mucus; Peristalsis; Plants, Medicinal; Rats; Rats, Wistar