Signalling pathways involved in ribonuclease-7 expression

Antimicrobial peptides are host defence molecules that play a potential role in preventing infection at the epithelial surfaces. Ribonuclease (RNase)-7 has been shown to possess a broad spectrum of microbicidal activity against various pathogens. Here, we demonstrate that RNase-7 protein is localised to the superficial layers of ocular surface cells and increased in response to interleukin (IL)-1β, suggesting an active role during inflammation related to ocular surface infection. Signal transduction pathways involved in RNase-7 expression are unknown. Involvement of transforming growth factor β-activated kinase-1 (TAK-1) activated nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathway molecules [c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38] were studied because of their importance in infection and inflammation. Blocking the MAPKs resulted in inhibition of RNase-7 expression in response to IL-1β. However, RNase-7 induction by IL-1β was not affected by inhibiting the NF-κB signalling pathway. In conclusion, our results indicate that RNase-7 expression is specifically mediated via MAPKs but not NF-κB signalling pathways.     

The relationship between the flexion reflex and certain ascending spinal pathways

Zusammenfassung Vier aufsteigende Rückenmarksbahnen werden bei spinalen Katzen durch somatische Afferenzen, die den Flexorreflex auslösen, beeinflusst. Genau wie beim Flexorreflex ist die Übertragung auf diese Bahnen bei dezerebrierten Katzen stark gehemmt. Die Regulierung der supraspinalen Hemmung der Bahnen und des Flexorreflexes scheint in gleicher Weise organisiert zu sein.     

Reticulospinal inhibition of transmission through interneurones of spinal reflex pathways

Résumé La transmission entre les afférences des réflexes de fléxion (FRA) et les motoneurones peut être inhibée par une stimulation de la formation réticulée bulbaire, sans qu'il se produise une dépolarisation des afférences primaires ou un potentiel postsynaptique des motoneurones. On conclut qu'il existe une inhibition des neurones intercalaires entre les afférences des réflexes de fléxion et les motoneurones.     

Monosynaptic reflex and natural sleep

Résumé Le réflexe monosynaptique (MSR) du nerf tibial ou du péronier a été observé chez le chat intact en expériences chroniques et non-anesthesié au cours des deux différentes phases du sommeil; la phase de hautvoltage ou des fuseaux et la phase paradoxale de basvoltage.Au cours de cette dernière, le MSR diminue d'amplitude, souvent même disparaît, et le seuil est toujours haut placé.     

Hyperventilation and inhibitory synapses

Summary Injection of a subconvulsive dose of strychnine (which blocked the inhibitory synapses) increases respiratory muscle activity evoked by stimulation of the sciatic nerve as well as by inhalation of hypercapnic gas mixture. Thus the inhibitory synapses prevent an excessive hyperventilation.     

Hyperventilation and inhibitory synapses.

Injection of a subconvulsive dose of strychnine (which blocked the inhibitory synapses) increases respiratory muscle activity evoked by stimulation of a sciatic nerve as well as by inhalation of hypercapnic gas mixture. Thus the inhibitory synapses prevent an excessive hyperventilation.     

Mechanisms involved in normal and pathological osteoclastogenesis

Osteoclasts are bone-resorbing cells that play an essential role in bone remodeling. Defects in osteoclasts result in unbalanced bone remodeling and are linked to many bone diseases including osteoporosis, rheumatoid arthritis, primary bone cancer, and skeletal metastases. Receptor activator of NF-kappaB ligand (RANKL) is a classical inducer of osteoclast formation. In the presence of macrophage-colony-stimulating factor, RANKL and co-stimulatory signals synergistically regulate osteoclastogenesis. However, recent discoveries of alternative pathways for RANKL-independent osteoclastogenesis have led to a reassessment of the traditional mechanisms that regulate osteoclast formation. In this review, we provide an overview of signaling pathways and other regulatory elements governing osteoclastogenesis. We also identify how osteoclastogenesis is altered in pathological conditions and discuss therapeutic targets in osteoclasts for the treatment of skeletal diseases.     

Sympathetic preganglionic pupillodilator fibres in the light reflex

Summary The modifications of the sympathetic pupillodilator activity in the light reflex have been demonstrated by recording the electrical discharge of single preganglionic fibres in the cervical sympathetic nerve.This work was supported by a grant of CNR.     

Mechanism of integration and excision in conjugative transposons

Translocation of conjugative transposons proceeds via excision of the element to generate a circular molecule that can then integrate into a new site, which can be in the same or a different cell. This review summarises some of the different mechanisms used for excision and integration of conjugative transposons. RID="*" ID="*"Corresponding author.     

Neuropeptides in pelvic afferent pathways

Neurochemical and pharmacological experiments have raised the possibility that several neuropeptides including, vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine amide (PHI), substance P, calcitonin gene-related peptide (CGRP), neurokinin A, cholecystokinin (CCK) and opioid peptides may be transmitters in afferent pathways to the pelvic viscera. These substances are widely distributed in: 1) nerve fibers in the pelvic organs, 2) visceral afferent neurons in the lumbosacral dorsal root ganglia and 3) at sites of afferent termination in the spinal cord. Double staining immunocytochemical techniques have shown that more than one peptide can be localized in individual visceral afferent neurons and that neuronal excitatory (VIP, substance P, CCK) and inhibitory peptides (leucine enkephalin) can coexist in the same afferent cell. Studies with the neurotoxin, capsaicin, indicate that peptidergic afferent pathways are involved in the initiation of central autonomic reflexes as well as peripheral axon reflexes which modulate smooth muscle activity, facilitate transmission in automatic ganglia and trigger local inflammatory responses.     

Neuropeptides in pelvic afferent pathways

Summary Neurochemical and pharmacological experiments have raised the possibility that several neuropeptides including, vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine amide (PHI), substance P, calcitonin gene-related peptide (CGRP), neurokinin A, cholecystokinin (CCK) and opioid peptides may be transmitters in afferent pathways to the pelvic viscera. These substances are widely distributed in: 1) nerve fibers in the pelvic organs, 2) visceral afferent neurons in the lumbosacral dorsal root ganglia and 3) at sites of afferent termination in the spinal cord. Double, staining immunocytochemical techniques have shown that more than one peptide can be localized in individual visceral afferent neurons and that neuronal excitatory (VIP, substance P, CCK) and inhibitory peptides (leucine enkephalin) can coexist in the same afferent cell. Studies with the neurotoxin, capsaicin, indicate that peptidergic afferent pathways are, involved in the initiation of central autonomic reflexes as well as peripheral axon reflexes which modulate smooth muscle activity, facilitate transmission in automatic ganglia and trigger local inflammatory responses.     

Factors involved in drug-produced model psychoses

Zusammenfassung Mezkalin, Methedrine (Pervitin), Lysergs?uremono?thylamid und Lysergs?uredi?thylamid weisen eine steigende Affinit?t zu Wollprotein auf. — Es scheint, dass zwischen der Dosis, welche von diesen Substanzen ben?tigt wird, um beim gesunden Menschen nach einmaliger Verabreichung Modellpsychosen ungef?hr vergleichbarer Intensit?t und Dauer hervorzurufen, einerseits und der Affinit?t derselben Substanzen zu Wollprotein andererseits eine umgekehrte Korrelation besteht.

---

---

Saskatchewan Commitee on Schizophrenia Research. Supported by the Department of National Health and Welfare, Ottawa.