This study was aimed to determine the effect of amygdaline inactivation on the sexual motivation of male rats during a T-maze task with a sexual reward. Subjects were chronically implanted with two stainless-steel can...This study was aimed to determine the effect of amygdaline inactivation on the sexual motivation of male rats during a T-maze task with a sexual reward. Subjects were chronically implanted with two stainless-steel cannulae that enabled the infusion of tetrodotoxin, a sodium channel blocker, into the left and right basolateral amygdala (BLA). Animals were divided into 3 groups: saline (SS);TTX1 (tetrodotoxin at 2.5 ng);and TTX2 (tetrodotoxin at 5.0 ng). To induce a sexually-motivated state, all male rats were allowed to have an intromission with a receptive female before performing the T-maze task, after which their sexual motivation was evaluated during seven trials in which a receptive female was placed in one goal-box of the T-maze, and a non-receptive one in the other. Subjects were allowed an intromission as a sexual reward whenever they reached the goal-box containing the receptive female, but were returned to the start-box if they did not. At the end of the experiment, copulation until ejaculation was permitted. Both doses of TTX increased the time rats required to cross the maze stem during the final trials. In terms of sexual interaction, the high dose of TTX increased more markedly mount, intromission and ejaculation latencies and the number of mounts and intromissions. Overall, these results indicate that the BLA may play an important role in modulating sexual behavior, particularly in maintaining sexual motivation in successive trials in a T-maze task and during sexual interaction per se.展开更多
OBJECTIVE:Angelica archangelica Linn.is widely used in food and liquor preparations and also in Kashmiri folk medicine to reduce anxiety.We evaluated the anxiolytic effect of successive extracts of A.archangelica linn...OBJECTIVE:Angelica archangelica Linn.is widely used in food and liquor preparations and also in Kashmiri folk medicine to reduce anxiety.We evaluated the anxiolytic effect of successive extracts of A.archangelica linn.(SAE) on rats tested in the elevated T-maze test(an animal model of generalized anxiety) at doses that exhibit antidepressant-like activity in humans.METHODS:A.archangelica(1 kg) was subjected to successive extraction in a soxhlet apparatus with solvents [petroleum ether(40-60℃),chloroform,ethyl acetate,methanol and decoction with water] in order of increasing polarity(yield:6.9%,7.3%,5.1%,11.88% and 8.2% w/w,respectively).SAE were evaluated for anxiolytic effects using the elevated T-maze and forced swimming tests in rats.RESULTS:Oral dosing of diazepam(1 mg/kg) and extracts(50,100 and 200 mg/kg) clearly showed an anxiolytic-like profile in the elevated T-maze test:it increased one-way escape and decreased inhibitory avoidance on the first,third and seventh day.In the forced swimming test,imipramine and SAE showed antidepressant-and anxiolytic-like effects as reflected by increased climbing time,swimming time and decreased immobility time on the first,third and seventh day.Aqueous and methanol extracts showed the most,petroleum ether(40-60℃) and chloroform intermediate,and ethyl acetate the least anxiolytic activity(*P<0.05,**P<0.01,***P< 0.001) in both models.CONCLUSIONS:These results suggest the anti-anxiety activity of various extracts of A.archangelica and strongly justify its use in traditional Indian medicine for the treatment of anxiety.展开更多
In this study, a T-maze-based frustration model in rats was established using sucrose-reward deprivation, The results revealed that rats maintained a 75% preference for the sucrose-reward arm in the reward phase. Duri...In this study, a T-maze-based frustration model in rats was established using sucrose-reward deprivation, The results revealed that rats maintained a 75% preference for the sucrose-reward arm in the reward phase. During the sucrose-deprivation frustration phase, both the preference for the sucrose-deprivation arm （62.5%） and time spent waiting in the sucrose-deprivation arm decreased. Acute injection of morphine increased the preference in a dose-dependent fashion, and prolonged the waiting duration in the sucrose-deprivation arm. These findings indicate that morphine specifically inhibited the frustration response induced by sucrose reward deprivation. To further elucidate the pharmacological mechanisms involved, the opioid receptor antagonist naloxone was given to model rats prior to the injection of morphine. The results revealed that naloxone administration markedly attenuated the anti-frustration-like effects of 3 mg/kg morphine treatment. These findings suggest that morphine attenuates the frustration-like response to reward deprivation in rats through the opioid receptor.展开更多
文摘This study was aimed to determine the effect of amygdaline inactivation on the sexual motivation of male rats during a T-maze task with a sexual reward. Subjects were chronically implanted with two stainless-steel cannulae that enabled the infusion of tetrodotoxin, a sodium channel blocker, into the left and right basolateral amygdala (BLA). Animals were divided into 3 groups: saline (SS);TTX1 (tetrodotoxin at 2.5 ng);and TTX2 (tetrodotoxin at 5.0 ng). To induce a sexually-motivated state, all male rats were allowed to have an intromission with a receptive female before performing the T-maze task, after which their sexual motivation was evaluated during seven trials in which a receptive female was placed in one goal-box of the T-maze, and a non-receptive one in the other. Subjects were allowed an intromission as a sexual reward whenever they reached the goal-box containing the receptive female, but were returned to the start-box if they did not. At the end of the experiment, copulation until ejaculation was permitted. Both doses of TTX increased the time rats required to cross the maze stem during the final trials. In terms of sexual interaction, the high dose of TTX increased more markedly mount, intromission and ejaculation latencies and the number of mounts and intromissions. Overall, these results indicate that the BLA may play an important role in modulating sexual behavior, particularly in maintaining sexual motivation in successive trials in a T-maze task and during sexual interaction per se.
文摘OBJECTIVE:Angelica archangelica Linn.is widely used in food and liquor preparations and also in Kashmiri folk medicine to reduce anxiety.We evaluated the anxiolytic effect of successive extracts of A.archangelica linn.(SAE) on rats tested in the elevated T-maze test(an animal model of generalized anxiety) at doses that exhibit antidepressant-like activity in humans.METHODS:A.archangelica(1 kg) was subjected to successive extraction in a soxhlet apparatus with solvents [petroleum ether(40-60℃),chloroform,ethyl acetate,methanol and decoction with water] in order of increasing polarity(yield:6.9%,7.3%,5.1%,11.88% and 8.2% w/w,respectively).SAE were evaluated for anxiolytic effects using the elevated T-maze and forced swimming tests in rats.RESULTS:Oral dosing of diazepam(1 mg/kg) and extracts(50,100 and 200 mg/kg) clearly showed an anxiolytic-like profile in the elevated T-maze test:it increased one-way escape and decreased inhibitory avoidance on the first,third and seventh day.In the forced swimming test,imipramine and SAE showed antidepressant-and anxiolytic-like effects as reflected by increased climbing time,swimming time and decreased immobility time on the first,third and seventh day.Aqueous and methanol extracts showed the most,petroleum ether(40-60℃) and chloroform intermediate,and ethyl acetate the least anxiolytic activity(*P<0.05,**P<0.01,***P< 0.001) in both models.CONCLUSIONS:These results suggest the anti-anxiety activity of various extracts of A.archangelica and strongly justify its use in traditional Indian medicine for the treatment of anxiety.
基金the National Natural Science Foundation of China,No.30870894the National Basic Research Program of China,No.2009CB522000National Key Technology R&D Program in the 12th Five-Year Plan of China,No.2011BAK04B08
文摘In this study, a T-maze-based frustration model in rats was established using sucrose-reward deprivation, The results revealed that rats maintained a 75% preference for the sucrose-reward arm in the reward phase. During the sucrose-deprivation frustration phase, both the preference for the sucrose-deprivation arm （62.5%） and time spent waiting in the sucrose-deprivation arm decreased. Acute injection of morphine increased the preference in a dose-dependent fashion, and prolonged the waiting duration in the sucrose-deprivation arm. These findings indicate that morphine specifically inhibited the frustration response induced by sucrose reward deprivation. To further elucidate the pharmacological mechanisms involved, the opioid receptor antagonist naloxone was given to model rats prior to the injection of morphine. The results revealed that naloxone administration markedly attenuated the anti-frustration-like effects of 3 mg/kg morphine treatment. These findings suggest that morphine attenuates the frustration-like response to reward deprivation in rats through the opioid receptor.
