The fact that addiction crosses all socio-economic boundaries confirms that addiction is a disease, which affects the functioning of the brain and body. over time, addictions can seriously interfere with daily life. drug abuse is defined the numerous neuroadaptations and neuromodulations in the central nervous system (cns) which lead to compulsive and uncontrolled drug searching, tolerance, interdependence, withdrawal syndrome and other serious health and social problems. drug addiction, which can be determined as the forcible requesting and taking of drugs despite horrendous aftereffects or loss of control over drug use, is caused by long-lasting drug-induced changes that occur in certain brain regions. abuse of most substances will produce noticeable signs and symptoms. these may include physical or behavioral symptoms, most likely both. the frontal lobe allows a person to delay feelings of reward or enjoyment. in addition, the frontal lobe malfunctions and gratification is immediate. additional areas of the brain may also play a role in addiction. the anterior cingulate cortex and the nucleus accumbens, which is associated with enjoyable emotions, can enhance a person’s response when exposed to addictive substances and hippocampus which depends to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory. damage to this part by the drug has a direct impact on memory. morphine dependence is associated with long-term adaptive changes in the brain that involve genes expression, which control extracellular signals including hormones, neurotransmitters. role of the neuro protectives are the relative preservation of neuronal structure and/or function. the aim of this study was to investigate the alteration of cart expression in morphine addicted male rat following crocin administration in hippocampus nucleus.
Twenty male wistar rats weighing between 220 and 240 g were bought from pharmacology college of tehran university (tehran, iran) were used in the study. morphine injected with peritoneally with an escalating protocol for 21 days and crocin (0.8 mg/kg) i.p. every two days. the drugs were dissolved in sterile 0.9% saline and injected intraperitoneally at a volume of 1 ml/kg. animals were kept four per plexiglas cages (40 * 30 * 25 cm) with food and water freely available ad-libitum, under12:12-h light/dark cycle (light on at 07:00 a.m.) and the temperature maintained at 22 ± 2 ºc. before the start of an experiment, rats were first allowed to adapt to the laboratory conditions for a minimum of one week. rna extraction and cdna synthesis were performed and real-time pcr was measured by expression cart.
As the observed results that the morphine decreased the level of cart peptide (p≤0.05). moreover, crocin did not alter cart gene expression levels by itself (p>0.05). also, crocin restored decreased of cart gene expression induced by morphine (p<0.01).
Rewards genes and addiction studies have provided an improved mechanistic understanding of morphine addiction. different changes in genes expression are reflected in the distinct linkage in the nucleus of the brain like hippocampus. according to this study, it seems that crocin can stop the effect of morphine addiction in the molecular states. in other words, this protective transducer for controlling gene expression is mainly the genes that are useful in the drug addiction process and its complications.