Pharmacological properties of beta-amyrin palmitate, a novel centrally acting compound, isolated from Lobelia inflata leaves.

Abstract

Effects of beta-amyrin palmitate isolated from the leaves of Lobelia inflata were studied on the central nervous system of mice and were compared with those of antidepressant drugs, mianserin and imipramine. In the forced swimming test, beta-amyrin palmitate, like mianserin and imipramine, reduced the duration of immobility of mice significantly in a dose-dependent manner (5, 10 and 20 mg kg-1). beta-Amyrin palmitate (5, 10 and 20 mg kg-1) or mianserin (5, 10 and 20 mg kg-1) elicited a dose-related reduction in locomotor activity of mice and antagonized locomotor stimulation induced by methamphetamine. In contrast, imipramine (5, 10 and 20 mg kg-1) increased locomotor activity and potentiated methamphetamine-induced hyperactivity. beta-Amyrin palmitate showed no effect on reserpine-induced hypothermia, whilst mianserin (10 mg kg-1) and imipramine (10 and 20 mg kg-1) antagonized the reserpine-induced effect. Unlike imipramine, beta-amyrin palmitate and mianserin did not affect haloperidol-induced catalepsy, tetrabenazine-induced ptosis and apomorphine-induced stereotypy. beta-Amyrin palmitate and imipramine had no effects on the head-twitch response induced by 5-hydroxytryptophan, whereas mianserin (5, 10 and 20 mg kg-1) decreased it in a dose-dependent manner. A potentiating effect of beta-amyrin palmitate (5, 10 and 20 mg kg-1) on narcosis induced by sodium pentobarbitone was stronger than that of imipramine (10, 20 and 40 mg kg-1) but weaker than that of mianserin (2.5, 5 and 10 mg kg-1). These results suggest that beta-amyrin palmitate has similar properties in some respects to mianserin and might possess a sedative action.(ABSTRACT TRUNCATED AT 250 WORDS)

• Authors: A Subarnas, T Tadano, Y Oshima, K Kisara, Y Ohizumi
• Journal: The Journal of pharmacy and pharmacology (J Pharm Pharmacol) Vol. 45 Issue 6 Pg. 545-50 (Jun 1993) ISSN: 0022-3573 [Print] England
• PMID: 8103103 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Antidepressive Agents
• Plant Extracts
• Triterpenes
• beta-amyrin palmitate
• Mianserin
• Methamphetamine
• Oleanolic Acid
• Reserpine
• Haloperidol
• Apomorphine
• Imipramine
• Phenobarbital
• Tetrabenazine

Topics

• Animals
• Antidepressive Agents (pharmacology)
• Apomorphine (pharmacology)
• Blepharoptosis (chemically induced, drug therapy)
• Catalepsy (chemically induced, drug therapy)
• Central Nervous System (drug effects)
• Dose-Response Relationship, Drug
• Drug Interactions
• Haloperidol
• Hypothermia, Induced
• Imipramine (pharmacology)
• Male
• Methamphetamine (pharmacology)
• Mianserin (pharmacology)
• Mice
• Mice, Inbred Strains
• Motor Activity (drug effects)
• Oleanolic Acid (analogs & derivatives)
• Phenobarbital (pharmacology)
• Plant Extracts (pharmacology)
• Reserpine (pharmacology)
• Sleep (drug effects)
• Stereotyped Behavior (drug effects)
• Swimming
• Tetrabenazine
• Triterpenes (pharmacology)