EFFECT OF CISTANCHE MONGOLICA EXTRACT ON THE CENTRAL NERVOUS SYSTEM AND ITS PSYCHOPHARMACOLOGICAL PROPERTIES

Relevance. Depression is often accompanied by anxiety, psychomotor retardation and impaired cognitive function. A new psychotropic agent should therefore be assessed not only for antidepressant activity but also for its effects on behaviour, anxiety and neurotransmitter systems. Plants of the genus Cistanche are known for their neuroprotective properties, but the effects of C. mongolica, which grows in the deserts of the Fergana region and Karakalpakstan, on the central nervous system have not been studied before. Aim – to study the effects of Cistanche mongolica extract on locomotor activity, anxiety and the dopaminergic system in experimental animals. Materials and methods. Experiments were performed on male white mice (18–24 g). An extract of the aerial and underground parts of C. mongolica was administered orally at doses of 50, 100 and 200 mg/kg. The following methods were used: phenamine (amphetamine)-induced locomotor activity (7 mg/kg, s.c.), recorded over 4 hours; open field test (Hall C.); light–dark box test against pentylenetetrazole (20 mg/kg, s.c.); haloperidol-induced catalepsy (1.0 mg/kg, s.c.), recorded over 5 hours. Data were analysed using Student's t-test; differences at p≤0.05 were considered significant. Results. In the control group, phenamine increased locomotor activity to 152–160% of baseline at 1–3 hours. In the extract-treated groups this value fell to 74–111% at 3–4 hours (p≤0.05). The strongest effect was seen at 200 mg/kg: 106% at 2 hours versus 160% in the control group. In the open field test, locomotor activity was 9.2±1.3 in the control group, 14.6±2.8 at 50 mg/kg and 16.8±2.9 at 200 mg/kg (p≤0.05). At 200 mg/kg, exploratory activity also increased (11.2±2.7 vs 9.4±1.5). Rearing was recorded only at 100 and 200 mg/kg. The number of defecations decreased at all doses (0–1.0 vs 2.5). In the light–dark box test, pentylenetetrazole reduced the ratio of time spent in the light and dark compartments (K) to 0.31; in intact animals it was 0.49. With the extract, K was 1.34, 1.60 and 1.52 (p≤0.05), i.e. 4.3–5.2 times higher than in the control group. Haloperidol induced catalepsy lasting 58–120 s in the control group. At 50 mg/kg, the extract shortened catalepsy to 0–18 s (p≤0.05). At 100 and 200 mg/kg, catalepsy also remained significantly shorter than in the control group throughout the 5 hours (5–45 s and 0–65 s, respectively). Conclusion. Cistanche mongolica extract has a modulating effect on the central nervous system. It increases locomotor and exploratory activity but attenuates phenamine-induced hyperactivity. The extract shows marked anxiolytic activity and a dopamine-positive effect. These properties complement its antidepressant action and point to its potential use in depressive states accompanied by anxiety.