Effect of total alkaloid of Equisetum pratense on the contents of monoamine neurotransmitters in brain of rats

Yubin JI; Shiyong GAO

ABSTRACT

BACKGROUND:

It is needed in the treatment of yearly increased nervous and mental diseases to seek safe and effective sedatives and tranquilizers from natural drugs. It is found in the previous experiments that the total alkaloid of equisetum pratense (TAEP) has the satisfactory sedative and tranquitrzing actions.

OBJECTIVE:

To analyze the inhibitory effect of TAEP on the central nervous system.

DESIGN:

A randomized control study taking experiment animals as the observing objects.

SETTING:

The Post-doctor Scientific Research Station, Institute of Materia Medica, Harbin Shangye University.

PARTICIPANTS:

The experiment was carried out in the Department of Pharmacology, Heilongjiang University of Traditional Chinese Medicine between March 2002 and January 2003. The drug was TAEP, and 24 Wistar rats were used.

METHODS:

Twenty-four rats were randomly divided into 3 groups TAEP group (60 mg/kg), reserpine group (30 mg/kg) and saline group (the same volume), all the rats were given intraperitoneal injections of the above drugs in corresponding dosages, and then the contents of monoamine neurotransmitters in brain were determined by high performance liquid chromatography (HPLC)-electrochemistry (HPLC-EC) and HPLC-ultraviolet (HPLC-UV) respectively.MAIN OUTCOME

MEASURES:

The contents of monoamine neurotranmitters of norepinephrine, adrenalin, dopamine and 5-serotonin (5-HA) and its metabolites of DHPR, 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid in the striatum and marginal area of brain in rats were observed.

RESULTS:

There were 8 rats in each group both before and after the experiment without abnormalities or death. TAEP significantly lowered the contents of monoamine neurotranmitter but increased the contents of neutral and acidic metabolites of monoamine neurotranmitters in the striatum of rats. TAEP significantly decreased the monoamine neurotranmitters and significantly elevated the contents of monoamine metabolites of 5-HIAA and homovanillic acid, but insignificantly increased the content of DHPR in the marginal area of brain (P ＞ 0.05).

CONCLUSION:

The sedative and tranquilizing actions of TAEP are associated with the decreased contents of central monoamine neurotranmitters. TAEP has an action on the evacuation of monoamine which is similar to reserpine, which may be considered as one of the mechanisms of its sedative and tranquitrzing actions on central nerve system.