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Articles 1 - 4 of 4
Full-Text Articles in Medicine and Health Sciences
Effects Of A Beta Adrenergic Antagonist Combined With Vasodilators On Cardiac Arrhythmia In Ischemic-Induced Rat Hearts, Promporn Raksaseri, Wuthichai Klomkleaw, Suwanakiet Sawangkoon
Effects Of A Beta Adrenergic Antagonist Combined With Vasodilators On Cardiac Arrhythmia In Ischemic-Induced Rat Hearts, Promporn Raksaseri, Wuthichai Klomkleaw, Suwanakiet Sawangkoon
The Thai Journal of Veterinary Medicine
Sixty male Spraque-Dawley rats were used in this study. The hearts were isolated and placed on a constant-pressure Langendorff apparatus, and perfused with only Krebs-Henseleit buffer (control), atenolol, atenolol plus prazosin, and atenolol plus salbutamol. After that the left anterior descending artery was occluded for 8 minutes and reperfused for 30 minutes to induce cardiac arrhythmias. The left ventricular pressure and coronary flow rate were monitored, and ECGs were recorded to evaluate cardiac arrhythmias. The administration of atenolol (β1-adrenergic antagonist) combined with prazosin (α1-adrenergic antagonist) prolonged RR intervals whereas that of atenolol combined with salbutamol (β2-adrenergic antagonist) did not prolong …
Electrophysiological And Morphological Heterogeneity Of Slow Firing Neurons In Medial Septal/Diagonal Band Complex As Revealed By Cluster Analysis, E. R. Garrido-Sanabria, M. G. Perez, C. Banuelos, T. Reyna, S. Hernandez, María Teresa Castañeda Licón, Luis V. Colom
Electrophysiological And Morphological Heterogeneity Of Slow Firing Neurons In Medial Septal/Diagonal Band Complex As Revealed By Cluster Analysis, E. R. Garrido-Sanabria, M. G. Perez, C. Banuelos, T. Reyna, S. Hernandez, María Teresa Castañeda Licón, Luis V. Colom
Health & Biomedical Sciences Faculty Publications and Presentations
Slow firing septal neurons modulate hippocampal and neocortical functions. Electrophysiologically, it is unclear whether slow firing neurons belong to a homogeneous neuronal population. To address this issue, whole-cell patch recordings and neuronal reconstructions were performed on rat brain slices containing the medial septum/diagonal band complex (MS/DB). Slow firing neurons were identified by their low firing rate at threshold (< 5Hz) and lack of time-dependent inward rectification (Ih). Unsupervised cluster analysis was used to investigate whether slow firing neurons could be further classified into different subtypes. The parameters used for the cluster analysis included latency for first spike, slow afterhyperpolarizing potential, maximal frequency and action potential (AP) decay slope. Neurons were grouped into three major subtypes. The majority of neurons (55%) were grouped as cluster I. Cluster II (17% of neurons) exhibited longer latency for generation of the first action potential (246.5±20.1 ms). Cluster III (28% of neurons) exhibited higher maximal firing frequency (25.3±1.7 Hz) when compared to cluster I (12.3±0.9 Hz) and cluster II (11.8±1.1 Hz) neurons. Additionally, cluster III neurons exhibited faster action potentials at suprathreshold. Interestingly, cluster II neurons were frequently located in the medial septum whereas neurons in cluster I and III appeared scattered throughout all MS/DB regions. Sholl’s analysis revealed a more complex dendritic arborization in cluster III neurons. Cluster I and II neurons exhibited characteristics of “true” slow firing neurons whereas cluster III neurons exhibited higher frequency firing patterns. Several neurons were labeled with a cholinergic marker, Cy3-conjugated 192 IgG (p75NTR), and cholinergic neurons were found to be distributed among the three clusters. Our findings indicate that slow firing medial septal neurons are heterogeneous and that soma location is an important determinant of their electrophysiological properties. Thus, slow firing neurons from different septal regions have distinct functional properties, most likely related to their diverse connectivity.
Nicotine Sensitization In A Rodent Model Of Schizophrenia: A Comparison Of Adolescents, Adults, And Neurotrophic Factors., Marla Kay Perna
Nicotine Sensitization In A Rodent Model Of Schizophrenia: A Comparison Of Adolescents, Adults, And Neurotrophic Factors., Marla Kay Perna
Electronic Theses and Dissertations
The behavioral effects of nicotine on locomotor activity in a rodent model of psychosis were analyzed. This model is based on neonatal quinpriole treatment (a dopamine D2/D3 agonist) which causes increased D2 receptor sensitivity, a phenomenon known as D2 priming that is common in schizophrenia. D2-primed adolescent rats did not demonstrate nicotine-induced hypoactivity early in training, and males demonstrated more rapid sensitization to nicotine as compared to controls administered nicotine. D2-primed females administered nicotine demonstrated increased stereotypic behavior. D2-primed adult rats given nicotine demonstrated significantly more robust sensitization to nicotine than controls given nicotine. Brain-derived neurotrophic factor (BDNF) was analyzed …
Primary Sensory Neuron Addition In The Adult Rat Trigeminal Ganglion: Evidence For Neural Crest Glio-Neuronal Precursor Maturation, Alfonso Lagares, Hong-Yun Li, Xin-Fu Zhou, Carlos Avendano
Primary Sensory Neuron Addition In The Adult Rat Trigeminal Ganglion: Evidence For Neural Crest Glio-Neuronal Precursor Maturation, Alfonso Lagares, Hong-Yun Li, Xin-Fu Zhou, Carlos Avendano
Illawarra Health and Medical Research Institute
It is debated whether primary sensory neurons of the dorsal root ganglia increase the number in adult animals and, if so, whether the increase is attributable to postnatal neurogenesis or maturation of dormant, postmitotic precursors. Similar studies are lacking in the trigeminal ganglion (TG). Here we demonstrate by stereological methods that the number of neurons in the TG of adult male rats nearly doubles between the third and eighth months of age. The increase is mainly attributable to the addition of small, B-type neurons, with a smaller contribution of large, A-neurons. We looked for possible proliferative or maturation mechanisms that …