The influence of the medial septal nucleus (MSN) on hippocampal rhythmical slow activity (RSA) was investigated in hunger motivated free-moving rabbits. Single unit activity of 29 CA3 dorsal hippocampal neurones was studied under two paradigms viz., electrical stimulation (3v/1msec/5Hz) and chemical blockade of atropine-sensitive medial septal cells (dose of 5 micrograms in 5 microliters). The analysis of interspike interval sample histograms recorded with Apple II, along with single unit neuronal spikes recorded on polygraph showed bimodal pattern with two peaks; one at bin 10-20 (high frequency) and second at bin 100-300 (theta frequency). On stimulation of MSN, there was total suppression of bin 100-300 with peaks at bin 1-20 and at bin greater than 1000 (very low frequency). Blockade of cholinergic receptors at MSN showed reduction of bin 100-300 and peak at bin 700- greater than 1000; this was followed by gradual decrease of spike's amplitude and thereafter its total abolition. The results indicate that the septal region is not a pacemaker per se in the genesis of hippocampal RSA (theta rhythm), but serves more in the nature of a relay station for a number of inputs and that its influence on the hippocampal electrical activity depends on the integrity of cholinergic inputs, be it from hippocampus proper or from mid-brain reticular formation.
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Brain Struct Funct
January 2025
Department of Physiology and Neurobiology, Laboratory of Molecular and Systems Neurobiology, Eötvös Loránd University, Budapest, Hungary.
The lateral septum (LS) demonstrates activation in response to pup exposure in mothers, and its lesions eliminate maternal behaviors suggesting it is part of the maternal brain circuitry. This study shows that the density of pup-activated neurons in the ventral subdivision of the LS (LSv) is nearly equivalent to that in the medial preoptic area (MPOA), the major regulatory site of maternal behavior in rat dams. However, when somatosensory inputs including suckling were not allowed, pup-activation was markedly reduced in the LSv.
View Article and Find Full Text PDFEur Arch Otorhinolaryngol
January 2025
Kartal Dr.Lütfi Kırdar City Hospital, Radiology Clinic, İstanbul, Turkey.
Purpose: To compare the nasolacrimal and nasal anatomical parameters in cases of acquired primary nasolacrimal duct obstruction and acute dacryocystitis.
Methods: The study included 62 eyes of 31 patients. The eyes were divided into three groups: Group A, comprising eyes presenting with acute dacryocystitis; Group B, comprising eyes with nasolacrimal duct obstruction but no previous episodes of dacryocystitis; and Group C, comprising eyes with an patent nasolacrimal duct.
J Neurosci
January 2025
Laboratory of Reproductive Neurobiology, Hun-Ren Institute of Experimental Medicine, Budapest, 1083 Hungary;
While hypothalamic kisspeptin (KP) neurons play well-established roles in the estrogen-dependent regulation of reproduction, little is known about extrahypothalamic KP-producing (KP) neurons of the lateral septum. As established previously, expression in this region is low and regulated by estrogen receptor- and GABA receptor-dependent mechanisms. Our present experiments on knock-in mice revealed that transgene expression in the LS begins at P33-36 in females and P40-45 in males and is stimulated by estrogen receptor signaling.
View Article and Find Full Text PDFBrain Res Bull
January 2025
Psychophysiology Laboratory, Wannan Medical College, Wuhu, Anhui 241002, China. Electronic address:
Post-traumatic stress disorder (PTSD) is characterized by anxiety, excessive fear, distress, and weakness as symptoms of a psychiatric disorder. However, the mechanism associated with its symptoms such as anxiety-like behaviors is not well understood. It is aimed to investigate the underlying mechanisms of the medial septum (MS)-medial habenula (MHb) neural circuit modulating the anxiety-like behaviors of PTSD mice through in vivo fiber photometry recording, optogenetics, behavioral testing by open-field and elevated plus maze, fluorescent gold retrograde tracer technology, and viral tracer technology.
View Article and Find Full Text PDFPulmonary veno-occlusive disease (PVOD) is a lethal variant of pulmonary hypertension. The degree of pulmonary arterial involvement varies. Here, we compare two PVOD patients who were transplanted at 8 years of age, whereof one is a homozygous mutation carrier.
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