Male Wistar rats were initially conditioned and tested for a cocaine-associated place-preference (20 mg/kg). On the following day after the initial test, the animals were submitted to extinction training. This training consisted GANT61 clinical trial of daily sessions in which the subjects were alternatively confined during
30 min in the saline and cocaine-associated environment. However, 30 min before each extinction trial the animals received a systemic injection of D2 antagonist sulpiride. While one group was treated with a dose of 50 mg/kg (ip), the other group was treated with a dose of 100 mg/kg. An additional control group received injections of saline during extinction trials. Twenty-four hours after the last extinction trial, the animals were tested again for their preferences to cocaine and saline associated environments. Since one round of extinction trial was not sufficient to produce extinction of cocaine associated place preference, the animals were submitted to a second cycle of extinction trials and test. The systemic administration of the two doses of sulpiride (50 and 100 mg/kg) 30 min before each conditioning did not enhance CP-456773 in vivo the extinction of cocaine-associated place preference. This finding suggests that the D2 receptors are not involved in a acute protocol of extinction of cocaine-induced place preference. (C) 2009 Elsevier B.V. All rights reserved.”
secretion of triglyceride-rich very low-density lipoproteins (VLDL-TG) contributes to diabetic dyslipidemia. Earlier studies have indicated a possible role for the hypothalamus and autonomic nervous system in the regulation of VLDL-TG. In the current study, we investigated whether the autonomic nervous system and hypothalamic neuropeptide Y (NPY) release during fasting regulates hepatic VLDL-TG secretion. We report that, in fasted rats, an intact hypothalamic arcuate nucleus and hepatic sympathetic innervation are necessary to maintain VLDL-TG secretion. Furthermore, the hepatic sympathetic innervation is necessary to mediate the stimulatory effect of intracerebroventricular administration of NPY on VLDL-TG secretion. Since the intracerebroventicular administration
of NPY increases VLDL-TG secretion by the liver without affecting lipolysis, its effect on lipid metabolism selleck inhibitor appears to be selective to the liver. Together, our findings indicate that the increased release of NPY during fasting stimulates the sympathetic nervous system to maintain VLDL-TG secretion at a postprandial level. Diabetes 61:1043-1050, 2012″
“Tetrahydrobiopterine (6BH(4)) can diminish the oxidative stress undergone by keratinocytes and melanocytes by reducing the o-quinones generated by the oxidation of the corresponding o-diphenols. We found that 6BH(4) and their analogs reduced all the o-quinones studied. The formal potentials of different quinone/diphenol pairs indicate that the o-quinones with withdrawing groups are more potent oxidants than those with donating groups.