The significance of endoplasmic reticulum (ER) store calcium in modulating transmitter release is slowly gaining recognition. One transmitter system that might play an important role in store calcium modulation of transmitter release in the CNS is acetylcholine (ACh). The main olfactory bulb (OB) receives rich cholinergic innervation from the horizontal limb of the diagonal band of Broca and blocking cholinergic signaling in the bulb inhibits the ability of animals to discriminate between closely related odors. Here we show that exposing OB slices to carbamylcholine (CCh), a hydrolysis-resistant analog of Ach, increases gamma-aminobutyric acid (GABA) release at dendrodendritic synapses onto the mitral cells. This increase in transmitter release is mediated by the activation of the M1 class of muscarinic receptors and requires the mobilization of calcium from the ER. The site of action of CCh for this effect is developmentally regulated. In animals younger than postnatal day 10, the major action of CCh appears to be on mitral cells, enhancing GABA release by reciprocal signaling resulting from increased glutamate release from mitral cells. In animals older than postnatal day 10, CCh appears to modulate transmitter release from dendrites of the interneurons themselves. Our results point to modulation of inhibition as an important role for cholinergic signaling in the OB. Our data also strengthen the emerging idea of a role for store calcium in modulating transmitter release at CNS synapses.

Purpose of review Epilepsy and anticonvulsant medications may substantially alter endocrine homeostasis, including the male reproductive hormonal system. Recent findingsSeizures in medial temporal lobe structures, through their connectivity to the hypothalamus, alter the secretion of gonadotropins. Levels of circulating bioavailable testosterone are affected by changes in the level of binding proteins, which in turn may be affected by seizure medications. The use of older generation medications which induce the cytochrome P450 system is associated with an increase in sex hormone binding globulin and lower bioactive testosterone. Sexual dysfunction, including decreased libido and decreased potency, and infertility, is seen commonly in men with epilepsy., However, its relation to sex hormone levels remains unclear. Co-morbid depression and anxiety may be important confounding factors. Testosterone and sexual function appear not to be affected by the newer generation (non-inducing) anticonvulsants. SummaryEpilepsy and its drug treatments are associated with alterations in hormonal and sexual function in men. Further study is needed to clarify the precise mechanisms behind these alterations, as some of the data conflict. More attention should be paid to this issue in male patients with seizures; when appropriate, treatment for psychiatric co-morbidity and switches in anticonvulsant therapy may be worth consideration.

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To investigate the performance of seizure detection methods and nursing staff response in our epilepsy monitoring unit (EMU). Methods: We retrospectively reviewed 38 EMU patient admissions over a 1-year period capturing 133 epileptic and non-epileptic seizures with associated video-EEG data. We recorded detailed seizure event characteristics for further analysis. Results: Rates of seizure detection, alarm usage, and time to nursing response varied by seizure type. Patients self-activated the push button (PB) alarm for 31.1% of all seizures, but only 8.9% of focal impaired awareness (FIAS) and focal to bilateral tonic-clonic seizures (FBTCS). In comparison, the Persyst automated seizure alarm reliably detected both electrographic seizures (76.2% of electrographic seizures) and FIAS/FBTCS (87.2% of FIAS/FBTCS), with a false positive alarm rate (FAR) of 0.14/hour, or every 7.3 h.11.4% of all seizures went unrecognized by nursing staff, of which the majority (80.0%) were FIAS. The PB alarm was of higher yield for alerting nurses to focal aware seizures (FAS) and psychogenic non-epileptic seizures (PNES) versus FIAS and FBTCS (p < 0.001). In contrast, nurses relied more on the automated Persyst software alarm to detect FIAS (p < 0.001). Time to nursing response was no different following audible alarm onset for the PB compared to the Persyst alarms (p = 0.14). Conclusion: Automated seizure detection software plays an important role in our EMU in seizure recognition, particularly for alerting nurses to FIAS. More rigorous studies are needed to determine the best utilization of various monitoring techniques and to promote high quality standards and patient safety in the EMU.