Behavioral changes induced by cocaine in mice are modified by a hyperlipidic diet or recombinant leptin

Abstract

The objective of the present study was to determine if the acute behavioral effects of cocaine acutely administered intraperitoneally (ip) at doses of 5, 10 and 20 mg/kg on white male CF1 mice, 90 days of age, would be influenced by leptin acutely administered ip (at doses of 5, 10 and 20 µg/kg) or by endogenous leptin production enhanced by a high-fat diet. The acute behavioral effects of cocaine were evaluated in open-field, elevated plus-maze and forced swimming tests. Results were compared between a group of 80 mice consuming a balanced diet and a high-fat diet, and a group of 80 mice fed a commercially available rodent chow formula (Ralston Purina) but receiving recombinant leptin (rLeptin) or saline ip. Both the high-fatfed and rLeptin-treated mice showed decreased locomotion in the open-field test, spent more time in the open arms of the elevated plusmaze and showed less immobility time in the forced swimming test (F (1,68) = 7.834, P = 0.007). There was an interaction between diets and cocaine/saline treatments in locomotion (F (3,34) = 3.751, P = 0.020) and exploration (F (3,34) = 3.581, P = 0.024). These results suggest that anxiolytic effects and increased general activity were induced by leptin in cocaine-treated mice and that low leptin levels are associated with behavioral depression. Chronic changes in diet composition producing high leptin levels or rLeptin treatment may result in an altered response to cocaine in ethologic tests that measure degrees of anxiety and depression, which could be attributed to an antagonistic effect of leptin.

Updates on drug bioavailability and delivery to posterior segment of eye

“…Moreover, studies have shown that mice fed a high fat diet displayed lower frequencies of ambulation, rearing and grooming as compared to mice fed with a balanced diet. [57,58] These results were in agreement with our present studies as we have noticed decreased ambulation, rearing and grooming in cafeteria diet group as compared to a normal diet group. Treatment with CMPI groups showed a significant increase in ambulation, rearing and grooming suggesting its beneficial role in maintaining the physical activity and locomotor behavior.…”

Polydrug Use in Adolescence

“…The few studies performed in the plus maze with mice have shown that acute MDMA administration induces anxiogenic or anxiolytic effects that vary depending on the dose employed (Navarro et al 2002). Although all the available evidence supports an anxiogenic effect of acute cocaine administration in adult mice (Erhardt et al, 2006), cocaine did not affect the behaviours studied in the plus maze in our study. One possible explanation could be the different experimental conditions of the studies compared or a different dose-response curve to cocaine in adolescent versus adult mice.…”

Effects of Diene Valepotriates from Valeriana glechomifolia on Na+/K+-ATPase Activity in the Cortex and Hippocampus of Mice

“…Post hoc analysis indicated a significant decrease in mice immobility time caused by the acute or repeated administration of the positive control imipramine or VAL when compared to the vehicle-treated group. The immobility time of the vehicle-treated mice is in accordance to previous studies published elsewhere by our group [16,37,38] and others [39], which have used the same mouse strain.…”