Introduction: Motor learning consolidates in adulthood, and its defects begin to appear with aging. Ghrelin, an endogenous peptide, improves memory and learning, targeting dopaminergic circuits. While cytidine diphosphate choline (citicoline) is known as a common drug for enhancing memory and learning in aging, it is not recommended for adults due to its side effects. The current study aimed at investigating if ghrelin treatment would improve motor learning via the expression of a relevant gene. Methods: For this experimental study, adult male Wistar rats were randomly divided into five groups: control group, three groups of ghrelin treatment (0. 3, 1. 5, and 3 nmol/μ L), and one group with citicoline treatment. The injections were done intra-hippocampally. The motor learning rate was determined using the rotarod performance test by measuring the resistance to falling. Then the expression of dopamine receptor type D1 (Drd1) gene in the hippocampus was measured by a real-time polymerase chain reaction (PCR). Results: Ghrelin (3 nmol/μ L) and citicoline had similar and significant effects on motor learning improvement (P<0. 01). Both drugs significantly increased Drd1 gene expression (P <0. 001). Conclusion: Ghrelin, like citicoline, improves motor learning by altering the expression of Drd1 gene in the hippocampus.

Background: Many efforts have been made to find a proper animal model for Parkinson’s disease, in order to improve our knowledge about this disorder and find therapeutic approaches. Generally the reproducibility of experiments in laboratory animals is accompanied by some troubles. Therefore the validity of model is certified by certain behavioral tests. Thus the present study was aimed to find an accurate and reproducible rat model of Parkinson’s disease by rotenone.Methods: Male Wistar rats weighting 400±50 g (10-12 months) received several doses of rotenone (1, 2, 3 mg/kg) or its vehicle subcutaneously every 48 hours. Three behavioral tests (rotarod, rearing and bar) were run in order to check the development of model.Findings: Results indicated that rotenone (2 mg/kg/48h) was an efficient dose beside its low mortality. It was found that the latency time of rotarod test and movement skills in rearing test decreased significantly in rotenone (2 mg/kg/48h) treated animals (p<0.05). In addition, the results of bar test showed the augmentation of catalepsy in rotenone group compared to vehicle treated animals (p<0.05). In addition the statistical correlation between behavioral tests justified the development of movement disorders in the model.Conclusion: According to the results, it was concluded that rotenone (2 mg/kg/48h) was the best approach with reproducible capacity for induction of Parkinson’s disease model.

Background: Folic acid (folate) which is a water-soluble vitamin-B is essential for the life-sustaining processes of DNA synthesis, replication, repair, and also protein synthesis.  Experimental evidence suggests that folate deficiency and its consequent elevated homocysteine level sensitize dopaminergic neurons to environmental toxin, whereby folate deficiency may influence risk of Parkinson disease. Accordingly, in this study, the effects of different doses of folic acid on motor activity of rat were studied using rotarod apparatus.Materials and Methods: Animals were divided into four groups and were injected intraperitonealy a single dose of folic acid or vehicle/day for one week. The there test groups received 5, 10 and 15 mg/kg/day folic acid and the sham group received saline. Then, all groups were introduced to the rotarod test. Results: The results showed that 5 mg/kg/day of folic acid significantly improves motor coordination (P<0.05). Conclusion: Overally, the present results indicate that low-dose folic acid improves motor performance of the rats.

Background: Potentilla species have traditionally been used as anti-inflammatory and analgesic agents in Iran and other countries. Objectives: This study aimed to investigate the antinociceptive effect of Potentilla reptans L., which has a wide distribution in the north of Iran. Methods: The biological activities of the hydroalcoholic extract of P. reptans aerial parts have been investigated using the acetic acid-induced writhing, hot plate, and rotarod tests in the male mice. In addition, the phytochemical profile of the extract has been evaluated. Results: The phytochemical investigation detected secondary metabolites such as flavonoids, saponins, triterpenoids, and tannins in the extract. Moreover, the Mean±, SD total phenolic and tannin contents of the extract were 251±, 2. 08 and 111. 5±, 1. 3 mg gallic acid equivalents per gram of dried extract, respectively. Also, the Mean±, SD total flavonoid content was 29. 42±, 3. 31 mg quercetin equivalents per gram of dried extract. Oral administration of the extract (100, 300, and 500 mg/kg) dose-dependently reduced the number of writhing responses induced by acetic acid and increased the reaction time in the hot-plate test. The antinociceptive effect of the extract, similar to morphine, was significantly antagonized by naloxone (4 mg/kg,IP) in the writhing test. In the rotarod test, none of the extract doses used in the experiment caused a loss of locomotor activity. Conclusion: In this study, the hydroalcoholic extract of P. reptans showed a practical antinociceptive effect in hot plate and writhing tests. It seems that opioid receptors mediate the observed effect.

BACKGROUND: Parkinson’s disease (PD) is a neurodegenerative disorder that involves approximately 1% of the population older than 50 years. Classically, PD is considered a motor system disease, and its diagnosis is based on the presence of a set of cardinal motoric signs (e.g. rigidity, bradykinesia, motor and postural reflex disturbance).OBJECTIVES: The present study aimed to evaluate the effects of hydro-alcoholic extract of lavender (Lavandula officinalis) on motor disorders of pseudo PD rats. METHODS: Male Wistar rats were divided into four groups (n=7). PD signs were induced by intra-peritoneal (IP) injection of reserpine (5mg/kg) prior to administration of the lavender extract. Three goups of rats received different doses (200, 300, 400 mg/kg, P.O) of the lavender extract and sham group received distilled water at the same volume for six days and two times per day. At the seventh day, Catalepsy and other signs of PD were measured in the bar test, rotarod and open field.RESULTS: In this study, improvement in signs of Parkinson disease were not observed by applying lavender hydro-alcoholic extract and motor disorders were not reduced in comparison with sham group.CONCLUSIONS: The lavender hydro-alcoholic extract does not have any effect on motor disorders of Parkinson disease.