Effects of pentylenetetrazole-induced status epilepticus on behavior, emotional memory and learning in immature rats

Status epilepticus (SE) can be harmful to the developing brain. Our knowledge of the emotional and behavioral consequences of generalized SE in developing animals remains limited. Therefore, we investigated the short- and long-term effects of pentylenetetrazole (PTZ)-induced SE on emotional memory and learning and behavioral parameters in immature rats. SE was induced in 16- to 20-day-old rats (P16-P20) using intraperitoneal injections of PTZ (n = 21); control rats received saline (n = 10). All animals were tested using an elevated T-maze and open-field test 2, 14, 30, and 180 days after SE, to evaluate emotional memory and learning and behavior. Anxiety levels decreased 2 and 14 days after SE, and conditioned learning of PTZ-treated immature rats was better than that of the control rats. These results indicate that a decreased anxiety level facilitates conditioned learning. Behavioral changes are transient, and no emotional memory or learning deficits occur following PTZ-induced SE in immature rats. (c) 2005 Elsevier Inc. All rights reserved. Epilepsy Behav. 2005 Jun;6(4):537-42. Epub 2005 Apr 26. Effects of pentylenetetrazole-induced status epilepticus on behavior, emotional memory and learning in immature rats. Erdoğan F, G&ouml;lgeli A, K&uuml;&ccedil;&uuml;k A, Arman F, Karaman Y, Ersoy A. Author information Neurology Department, Erciyes University, 38039 Kayseri, Turkey. [email protected] Abstract Status epilepticus (SE) can be harmful to the developing brain. Our knowledge of the emotional and behavioral consequences of generalized SE in developing animals remains limited. Therefore, we investigated the short- and long-term effects of pentylenetetrazole (PTZ)-induced SE on emotional memory and learning and behavioral parameters in immature rats. SE was induced in 16- to 20-day-old rats (P16-P20) using intraperitoneal injections of PTZ (n=21); control rats received saline (n=10). All animals were tested using an elevated T-maze and open-field test 2, 14, 30, and 180 days after SE, to evaluate emotional memory and learning and behavior. Anxiety levels decreased 2 and 14 days after SE, and conditioned learning of PTZ-treated immature rats was better than that of the control rats. These results indicate that a decreased anxiety level facilitates conditioned learning. Behavioral changes are transient, and no emotional memory or learning deficits occur following PTZ-induced SE in immature rats. &nbsp;</p

Gender differences revealed in the right posterior temporal areas during Navon letter identification tasks

Gender differences in temporo-spectral EEG patterns during verbal cognitive performance are poorly understood. The aim of the present study was to examine whether the event-related dynamics of EEG differ between genders during the performance of Navon letter identification tasks (NLITs). To this end, the EEG patterns of 40 subjects were recorded during the NLIT performance. We compared behavioral outcomes, event-related temporo-spectral dynamics, and source distribution of neural oscillations within cortical regions of male and female subjects. We found that male subjects exhibited greater induced neural activities than female subjects in right temporo-parietal areas at theta and alpha frequency bands. Source imaging for the time ranges at which maximal gender differences were observed revealed gender-dependent estimated current densities in the right posterior temporal regions. These gender differences can be explained by the existence of distinct, gender-specific hemispheric specialization. Thus, gender differences should be considered during behavioral tasks and electrophysiological measurements

Sheehan syndrome

WOS: 000397870700001PubMed ID: 28004764Sheehan syndrome or postpartum hypopituitarism is a condition characterized by hypopituitarism due to necrosis of the pituitary gland. The initial insult is caused by massive postpartum haemorrhage (PPH), leading to impaired blood supply to the pituitary gland, which has become enlarged during pregnancy. Small sella turcica size, vasospasms (caused by PPH) and/or thrombosis (associated with pregnancy or coagulation disorders) are predisposing factors; autoimmunity might be involved in the progressive worsening of pituitary functions. Symptoms are caused by a decrease or absence of one or more of the pituitary hormones, and vary, among others, from failure to lactate and nonspecific symptoms (such as fatigue) to severe adrenal crisis. In accordance with the location of hormone-secreting cells relative to the vasculature, the secretion of growth hormone and prolactin is most commonly affected, followed by follicle-stimulating hormone and luteinizing hormone; severe necrosis of the pituitary gland also affects the secretion of thyroid-stimulating hormone and adrenocorticotropic hormone. Symptoms usually become evident years after delivery, but can, in rare cases, develop acutely. The incidence of Sheehan syndrome depends, to a large extent, on the occurrence and management of PPH. Sheehan syndrome is an important cause of hypopituitarism in developing countries, but has become rare in developed countries. Diagnosis is based on clinical manifestations combined with a history of severe PPH; hormone levels and/or stimulation tests can confirm clinical suspicion. Hormone replacement therapy is the only available management option so far