Further experiments extended these findings.
Experiment 1 infused pre-session intra-amygdala R(+) 7-OH-DPAT (0, selleck 0.1, 1 nmol) during conditioned approach acquisition. Experiment 2 applied pre-session intra-amygdala R(+) 7-OH-DPAT (0, 0.01, 0.1, 1 nmol) during expression of the same response, once well learned. Experiment 3 required the inhibition of a conditioned approach response following unconditioned stimulus (US) removal. Experiment 4 examined the ability of animals with prior drug experience to acquire a conditioned response to a novel stimulus.
Experiments 1-3 showed that pre-session amygdala
R(+) 7-OH-DPAT impaired acquisition of either excitatory or inhibitory conditioned responding, but was ineffective following overtraining. Drug-induced
impairments in acquisition of a specific conditioned stimulus (CS)-US relationship continued well beyond the cessation of drug treatment, but were found not to transfer to an alternate CS in Experiment 4.
Pre-session dopamine receptor activation within the amygdala may impair the acquisition, but not expression, of CS-US associations. Enhanced learning reported earlier following post-session dopamine receptor activation may occur indirectly through reduced interference with the consolidation of recent learning.”
“Introduction: this website In peptide receptor radionuclide therapy for neuroendocrine tumors the main dose-limiting tissue is found in the kidneys because of tubular reabsorption and retention of radioactivity. The aim of this check details study was to quantify late effects in renal cortex of nude mice exposed to high amounts of [Lu-177]-DOTA-Tyr(3)-octreotate [Lu-177]-DOTATATE), and to determine whether a threshold dose value exists
for these findings.
Methods: Nude mice were exposed to 90, 120 or 150 MBq of [Lu-177]-DOTATATE. Renal toxicity was evaluated up to 6 months after injection. Blood samples were collected to examine renal functional markers, and after sacrifice at 6 months changes in renal morphology were explored. Tissue damage was estimated by quantifying the relative area of the different subunits in the renal cortex using point counting. Additional morphological signs of radiation damage were also noted. The absorbed doses to the kidneys were estimated by previously determined kidney pharmacokinetics and Monte Carlo simulations for different assumptions regarding the activity distribution.
Results: Increased serum creatinine and urea values indicated long-term renal toxicity. The tissue area occupied by proximal tubules decreased with increasing doses of [Lu-177]-DOTATATE, whereas the other subunits in cortex slightly increased. The mean absorbed dose in the renal cortex for [Lu-177]-DOTATATE was estimated to be 35-58 Gy for the different groups of animals.