Articles by Onur Güntürkün in JoVE
Recording Single Neurons' Action Potentials from Freely Moving Pigeons Across Three Stages of Learning Sarah Starosta*1, Maik C. Stüttgen*1, Onur Güntürkün1 1Faculty of Psychology, Department of Biopsychology, Ruhr-University Bochum Learning new stimulus-response associations engages a wide range of neural processes which are ultimately reflected in changing spike output of individual neurons. Here we describe a behavioral protocol allowing for the continuous registration of single-neuron activity while animals acquire, extinguish, and reacquire a conditioned response within a single experimental session.
Other articles by Onur Güntürkün on PubMed
Genotoxic Effects and LC50 Value of NaOCl on Orthrias Angorae (Steindachner 1897) Bulletin of Environmental Contamination and Toxicology. Jun, 2008 | Pubmed ID: 18389161 Studies show that different organisms used as bio-indicators have indicated several genotoxic and mutagenic effects of disinfected waters. In this study, the 96 h LC(50 )mean value of NaOCl for Orthrias angorae was calculated to be 0.5509 mg/L. The results showed that NaOCl is highly toxic to O. angorae specimens. Statistical analysis demonstrated a significant increase in micronuclei after the induction of 0.5 mg/L NaOCl concentration after 36 h. The same increase has been reported for 0.37 and 0.5 mg/L NaOCl concentrations after 72 h. Even though the MN frequency of 0.37 mg/L was similar after 36 and 72 h, only 72 h micronuclei frequency was statistically significant. The 72 h MN frequency of the negative control group was smaller than 36 h MN frequency of the negative control group. This discrepancy has led to 72 h MN frequency being statistically significant. MN frequency of 0.25 mg/L NaOCl concentration was insignificant when compared to negative test groups. The benzene treatment also caused a significant increase (p < 0.01) in the frequency of micronucleated erythrocytes.
Distribution of Glutathione Peroxidase 1 in Liver Tissues of Healthy and Diabetic Rats Treated with Capsaisin Biotechnic & Histochemistry : Official Publication of the Biological Stain Commission. May, 2014 | Pubmed ID: 24867493 We investigated the immunohistochemical localization of glutathione peroxidase 1 (GPx 1) and the structural changes that occur in the livers of healthy and diabetic rats that were treated with capsaisin (CAP). Fifty female rats were divided into five groups: group 1, sham; group 2, untreated control; group 3, CAP-treated; group 4, streptozotocin (STZ) diabetic; group 5, STZ diabetic + CAP-treated. STZ was administered to groups 4 and 5; after verifying diabetes, CAP was administered daily for 2 weeks to groups 3 and 5. Diffuse, microvesicular and some macrovesicular fatty degeneration were observed in the cytoplasms of hepatocytes in the livers of the diabetic group. In the CAP-treated diabetic group, fat degeneration in the livers decreased slightly by day 7. Irregularity of the external contours of nuclei of the hepatocytes, swelling of the nuclei, and slight anisocytosis and anisokaryosis were observed in the hepatocytes of the diabetic group. In the CAP-treated diabetic groups, the severity of anisocytosis and anisokaryosis decreased slightly by day 7. In all groups, GPx 1 showed similar immunolocalization, but in the diabetic and diabetic + CAP groups, GPx 1 immunoreactivity was less than in the other groups. GPx 1 immunoreactivity in the CAP-treated diabetic group was weaker than in the diabetic group. In all groups, GPx 1 immunoreactivity was diffusely cytoplasmic in some of the hepatocytes, and diffusely cytoplasmic and diffusely nuclear in other hepatocytes. Also, GPx 1 immunoreactivity in the liver was more intense in the hepatocytes around Kiernan's space. We found that CAP caused a decrease in GPx 1.