Unal Zagli - Academia.edu (original) (raw)
Related Authors
Università degli Studi "La Sapienza" di Roma
Uploads
Papers by Unal Zagli
Life Sciences, 2002
Involvement of T-type voltage dependent Ca2+ channels (VDCCs) on morphine antinociception, in the... more Involvement of T-type voltage dependent Ca2+ channels (VDCCs) on morphine antinociception, in the development of tolerance and dependence to morphine, and naloxone-precipitated abstinence syndrome in morphine dependent mice was examined by using mibefradil, a T-type VDCCs blocker. Mice were rendered tolerant and dependent on morphine by subcutaneous (s.c.) implantation of a morphine pellet containing 75 mg of morphine base for
Life Sciences, 2002
Involvement of T-type voltage dependent Ca 2+ channels (VDCCs) on morphine antinociception, in th... more Involvement of T-type voltage dependent Ca 2+ channels (VDCCs) on morphine antinociception, in the development of tolerance and dependence to morphine, and naloxone-precipitated abstinence syndrome in morphine dependent mice was examined by using mibefradil, a T-type VDCCs blocker. Mice were rendered tolerant and dependent on morphine by subcutaneous (s.c.) implantation of a morphine pellet containing 75 mg of morphine base for 72 hr. The tail-flick test was used to assess the nociceptive threshold. Coadministration of acute mibefradil (10 mg/kg, i.p.) with morphine enhanced the antinociceptive effects of acute morphine. Repeated mibefradil administration (10 mg/kg, i.p., just before, 24 and 48 hr after morphine pellet implantation) completely blocked the development of tolerance to the antinociceptive effect of morphine and even by this effect reached supersensitivity to morphine. However, repeated mibefradil treatment did not alter the development of dependence to morphine assessed by the A 50 values of naloxone (s.c.) required to precipitate withdrawal jumping 72 hr after morphine pellet. But, acute mibefradil (10, 30, and 50 mg/kg, i.p.) dose dependently decreased the expression of morphine abstinence syndrome when given directly 30 min prior to naloxone (0,05 mg/kg, s.c.) 72 hr after morphine pellet. These results indicate a critical role of T-type VDCCs in morphine antinociception, the development of tolerance to the antinociceptive effects of morphine and in morphine abstinence syndrome.
Drug and Alcohol Dependence, 1999
Effects of N G-nitroarginine methyl ester (L-NAME), a nonspecific inhibitor of nitric oxide (NO) ... more Effects of N G-nitroarginine methyl ester (L-NAME), a nonspecific inhibitor of nitric oxide (NO) synthase, on amphetamine-induced locomotor activity were investigated in Swiss-Webster mice. Locomotor activity was measured for 30 min immediately following amphetamine (1, 2 and 4 mg/kg, i.p.) or saline treatments. L-NAME (15 and 30 mg/kg) and a combination of L-arginine (1000 mg/kg) and L-NAME (30 mg/kg) were injected 30 min before amphetamine (2 mg/kg) to other groups of the mice. L-Arginine was injected 30 min before L-NAME treatment when they were combined. L-NAME (30 mg/kg) and L-arginine (1000 mg/kg) were also tested for ability to depress or stimulate locomotor activity in the absence of amphetamine. Amphetamine caused a dose-dependent increase in locomotor activity of the mice. L-NAME blocked the amphetamine-induced locomotor stimulation dose dependently. L-Arginine pretreatment prevented the inhibitory effects of L-NAME on amphetamine-induced locomotor stimulation. L-NAME and L-arginine did not cause any significant change in locomotor activity in mice not treated with amphetamine. These results suggest that amphetamine-induced locomotor stimulation in mice is modulated by NO.
Life Sciences, 2002
Involvement of T-type voltage dependent Ca2+ channels (VDCCs) on morphine antinociception, in the... more Involvement of T-type voltage dependent Ca2+ channels (VDCCs) on morphine antinociception, in the development of tolerance and dependence to morphine, and naloxone-precipitated abstinence syndrome in morphine dependent mice was examined by using mibefradil, a T-type VDCCs blocker. Mice were rendered tolerant and dependent on morphine by subcutaneous (s.c.) implantation of a morphine pellet containing 75 mg of morphine base for
Life Sciences, 2002
Involvement of T-type voltage dependent Ca 2+ channels (VDCCs) on morphine antinociception, in th... more Involvement of T-type voltage dependent Ca 2+ channels (VDCCs) on morphine antinociception, in the development of tolerance and dependence to morphine, and naloxone-precipitated abstinence syndrome in morphine dependent mice was examined by using mibefradil, a T-type VDCCs blocker. Mice were rendered tolerant and dependent on morphine by subcutaneous (s.c.) implantation of a morphine pellet containing 75 mg of morphine base for 72 hr. The tail-flick test was used to assess the nociceptive threshold. Coadministration of acute mibefradil (10 mg/kg, i.p.) with morphine enhanced the antinociceptive effects of acute morphine. Repeated mibefradil administration (10 mg/kg, i.p., just before, 24 and 48 hr after morphine pellet implantation) completely blocked the development of tolerance to the antinociceptive effect of morphine and even by this effect reached supersensitivity to morphine. However, repeated mibefradil treatment did not alter the development of dependence to morphine assessed by the A 50 values of naloxone (s.c.) required to precipitate withdrawal jumping 72 hr after morphine pellet. But, acute mibefradil (10, 30, and 50 mg/kg, i.p.) dose dependently decreased the expression of morphine abstinence syndrome when given directly 30 min prior to naloxone (0,05 mg/kg, s.c.) 72 hr after morphine pellet. These results indicate a critical role of T-type VDCCs in morphine antinociception, the development of tolerance to the antinociceptive effects of morphine and in morphine abstinence syndrome.
Drug and Alcohol Dependence, 1999
Effects of N G-nitroarginine methyl ester (L-NAME), a nonspecific inhibitor of nitric oxide (NO) ... more Effects of N G-nitroarginine methyl ester (L-NAME), a nonspecific inhibitor of nitric oxide (NO) synthase, on amphetamine-induced locomotor activity were investigated in Swiss-Webster mice. Locomotor activity was measured for 30 min immediately following amphetamine (1, 2 and 4 mg/kg, i.p.) or saline treatments. L-NAME (15 and 30 mg/kg) and a combination of L-arginine (1000 mg/kg) and L-NAME (30 mg/kg) were injected 30 min before amphetamine (2 mg/kg) to other groups of the mice. L-Arginine was injected 30 min before L-NAME treatment when they were combined. L-NAME (30 mg/kg) and L-arginine (1000 mg/kg) were also tested for ability to depress or stimulate locomotor activity in the absence of amphetamine. Amphetamine caused a dose-dependent increase in locomotor activity of the mice. L-NAME blocked the amphetamine-induced locomotor stimulation dose dependently. L-Arginine pretreatment prevented the inhibitory effects of L-NAME on amphetamine-induced locomotor stimulation. L-NAME and L-arginine did not cause any significant change in locomotor activity in mice not treated with amphetamine. These results suggest that amphetamine-induced locomotor stimulation in mice is modulated by NO.