Evidence that brain capillary endothelial cells can be infected with murine leukaemia retrovirus, LP-BM5

The effect of intraportal administrations of interleukin 1 beta (IL-1 beta) on the afferent activity of the hepatic branch of the vagus nerve was observed in urethane anesthetized rats. An intraportal injection of IL-1 beta in doses of 10 pg and 100 pg per animal (300-400 g body wt.) resulted in dose-dependent increase in the afferent activity, which lasted about 70-100 min. Further, intraportal injection of IL-1 beta (100 pg) induced reflex activation of efferent activity of the splenic (sympathetic) nerve and vagal thymic nerve. This reflex activation was not observed in hepatic vagotomized rat and after an administration of the same dose of IL-1 beta into the systemic vein in normal rat. The results suggest the existence of sensors for IL-1 beta which send information on IL-1 beta in the portal venous blood to the central nervous system through the hepatic branch of the vagus nerve and play some role in reflex regulation of immune function.     

Histophysiologic characteristics of the effector innervation of the arteries of the base of the brain during rat ontogenesis

The development of adren- and cholinergic nervous plexuses in the brain base arteries was studied by histochemical methods of Falck and Kelle in animals and fetuses of 10-22 days, newborn rats, animals of 10, 20, 30, 40, 60 and 120 days of life and 1 and 2 years old rats. The cholinergic nerve fibres were first found in the basilar, vertebral and internal carotid arteries on the 15th and 16th days of ontogenesis. Specific fluorescence of adrenergic conductors on the same arteries is revealed somewhat later--from the 17th and 18th days of the intrauterine development. Further formation of the cholin- and adrenergic innervation of the arteries of the Willis' circle goes on synchronously. The number of nerve fibres increases with the growth of the artery diameter. The concentration of catecholamines and the activity of AChE in them gradually increases. The greatest density of nerve fibres per 1 mm2 is determined in 20-day-old rats. The number of cholinergic nerve fibres on the arteries of the brain base is equal to that of adrenergic fibres during the whole period of postnatal ontogenesis. By the 30th day the effector nervous apparatus has a definite structure. In old rats the activity of AChE and the content of catecholamines drop, the amount and concentration of nerve fibres decrease.     

The morphogenic/cytotoxic and prostaglandin-stimulating activities of interleukin-1 beta in the rat ovary are nitric oxide independent

Nitric oxide (NO) has been implicated as a mediator of physiologic and pathologic cellular injury. Since the cytokine interleukin-1 beta (IL-1 beta) induces nitric oxide synthase (NOS) activity as well as effects morphogenic/cytotoxic changes and increased prostaglandin (PGE2) levels in cultured whole ovarian dispersates, we set out to determine whether these actions are interrelated. Treatment with IL-1 beta resulted in a marked increase in media nitrite and nitrate accumulation, morphological alterations, and increased release of lactate dehydrogenase (LDH) into media. Addition of IL-1 receptor antagonist (RA) eliminated these IL-1 beta effects. In contrast, specific inhibitors of NOS failed to reverse IL-1 beta-induced morphogenic changes or LDH release in spite of complete reduction of media nitrite to control levels. Similarly, treatment with transforming growth factor beta 1, inhibited IL-1 beta-induced nitrite accumulation, but had no effect on the morphologic or cytotoxic endpoints. Moreover, the addition of sodium nitroprusside, an NO generator, resulted in progressive increments in media nitrite content without a corresponding increase in the IL-1 beta-associated morphogenic changes or media LDH content. Furthermore, IL-1-induced PGE2 accumulation remained unaffected by specific NOS inhibition. These observations support the view that NO does not mediate the morphogenic/cytotoxic or inflammatory-like (e.g., PGE2 inducing) properties of IL-1 beta in cultured whole ovarian dispersates. Although the precise role of NO in ovarian physiology remains unknown, it is possible that NO participates in the periovulatory modulation of ovarian blood flow by virtue of its potent vasodilatory activity.     

Adrenergic innervation of the cerebral arteries following changes in the activity of cholinergic and monoaminergic brain systems

Bipolar electrical nerve stimulation decreased the adrenergic innervation density and the catecholamine content in the rat isolated caudal artery. Changes in cholinesterase activity and catecholamine content in histochemically active nerves following administration of cholinesterase (AChE) inhibiting agent phosphacol, seem to reflect compensatory responses to increasing dilatory cholinergic vasomotor effects under conditions of the AChE activity. Adrenergic innervation of cerebral arteries was also studied after a 1-hr daily hypoxic sessions. These decreased the catecholamines content as compared to the control.     

Vasoactive intestinal polypeptide (VIP)--immunoreactive nerve fibres in the mammary gland of the pig

Immunohistochemical studies have been performed to investigate the coexistence of VIP with dopamine-beta-hydroxylase (D(beta)H), vesicular acetylcholine transporter (VAChT), somatostatin (SOM) or neuropeptyd Y (NPY) within nerve fibres supplying the immature mammary gland in the pig. Generally, a moderate number of the VIP-immunoreactive (VIP-IR) nerve fibres were located in the nipple and parenchyma of the gland. VIP-IR fibres surrounded smooth muscle cells (SMC), blood vessels (BV) and lactiferous ducts (LD). Double-labelling immunohistochemistry revealed that some of VIP-IR nerve fibres also contained immunoreactivity to D(beta)H. VIP/D(beta)H-IR nerves were associated with BV and SMC and single fibres were observed around the LD in both nipple and parenchyma of the gland. VIP/VAChT-IR nerve fibres were not observed. The majority of VIP-IR fibres associated with SMC were also SOM-IR. Less numerous VIP/SOM-IR fibres supplied the BV and were located around the LD of the gland. A small number of VIP-IR nerves also displayed immunoreactivity to NPY. VIP/NPY-IR nerve fibres supplied the BV of the gland.     

Interleukin-1 beta differentially affects interleukin-6 and soluble interleukin-6 receptor in the blood and central nervous system of the monkey

Two studies were conducted to investigate whether behavioral and physiological responses induced by administration of interleukin-1 beta (IL-1 beta) were also associated with changes in interleukin-6 (IL-6) and soluble IL-6 receptor levels (sIL-6R). Following intravenous injection of rhIL-1 beta, blood and cerebrospinal fluid (CSF) samples were collected from juvenile rhesus monkeys. Marked increases in IL-6 levels were evident at 1 h in both blood and intrathecal compartments. IL-1 beta also induced significant elevations in the release of ACTH and cortisol into the blood stream, and following high doses, the monkeys evinced signs of sickness behavior. The second study characterized the IL-beta dose-response relationship showing that these physiological changes were most evident at doses between 0.5 microgram and 1.0 microgram IL-1/kg body weight. Soluble IL-6 receptor concentration was also increased, but only in plasma. There was no detectable sIL-6R in CSF. The large release of IL-6 into CSF suggests that some behavioral symptoms may be due to intrinsic changes in central nervous system activity concomitant with the alterations in peripheral physiology.     

Cytokine response to inactivated Candida albicans in mice

Inactivated Candida albicans (CA) cells induce strong activation of natural cytotoxic effectors in mice. In the present study we examined the expression of cytokine genes involved in the immune response to CA. It has been reported that differential cytokine production by natural immune cells is important for regulating the development of specific TH response. Northern blot analysis was performed on peritoneal exudate cells (PEC) recovered from CD2F1 mice injected ip with five doses of CA (CA-5d, on Days -14, -10, -7, -3, 0 with respect to the in vitro assays at 2, 24, and 72 hr) or from mice injected ip with four doses of CA (CA-4d, on Days -14, -10, -7, -3 with respect to the in vitro assay on Day 0). On Day 0, before the fifth CA injection, PEC expressed a high level of IL-2 and a low level of IL-1 beta mRNAs while genes coding for IL-4, IL-5, IL-6, IL-10, IL-12, TNF alpha, and IFN gamma were not expressed and there was a high level of NK activity. Two hours after CA-5d a high level of IFN gamma and a low level of IL-10 mRNAs were already evident, while IL-2 and much more IL-1 beta had greatly increased. IL-6, TNF alpha, and IL-2R alpha chain mRNAs were also detectable, whereas IL-4, IL-5, and IL-12 were not expressed. IL-12 mRNA was also absent in earlier stages of the CA sensitization. Both cellularity and NK activity of peritoneal exudate had increased with respect to Day 0. At 24 hr whereas IL-2 mRNA remained high, both IL-1 beta and IFN gamma mRNAs expression had decreased. Expression of other cytokines was no longer detectable but NK activity remained high and a significant LAK activity was also induced. After 72 hr, while the IL-2 mRNA level and NK activity were still high the IL-1 beta mRNA expression had further decreased. These results indicate that CA induces a predominant production of IFN gamma and IL-2, cytokines involved in the development of TH1 response but it is unable to induce IL-12. This secondary pathway, without IL-12 involvement in the development of TH1 response, is probably the result of the ability of IL-2, IL-1 beta, and TNF alpha to synergize in inducing IFN gamma synthesis by NK cells.     

Cytokine production in obsessive-compulsive disorder

Cytokine production was previously demonstrated to be reduced in untreated major affective patients. In addition, recovery from depression following clomipramine (CMI) treatment was accompanied by the restoration of interleukin-1 beta (IL-1 beta) and interleukin-3-like activity (IL-3-LA) to normal range. In the present study we assessed the in vitro production of IL-1 beta IL-2, and IL-3-LA by peripheral blood mononuclear cells (PBMC) in 11 nondepressed patients with obsessive compulsive disorder (OCD) before and after 8 weeks of CMI treatment. Results were compared with those of 11 healthy subjects. CMI treatment induced a significant improvement in OCD symptoms. No alteration was observed in cytokine production in OCD patients before treatment as compared to control subjects. Moreover, 8 weeks of drug treatment had no effect on cytokine production. In conclusion, OCD per se, as well as CMI treatment, have no effect on interleukin production as measured in this study.     

Endoscopic sclerotherapy is useful in Dieulafoy''s disease

1.5% Capsaicin (Cap) or Vehicle was respectively used to treat the right or left sciatic nerve in 20 Sprague-Dawley rats. On the seventh day, the 20 rats were at random divided into electroacupuncture (EA) group and non-EA group, the spinal cord corresponding to the afferent segments of sciatic nerve was taken out for observing the changes of acetylcholinesterase (AChE) activity and [3H]-quinuelidinylbenzylate (QNB) binding sites in the spinal dorsal horn (SDH). The results were as follows: (1) EA "Huantiao" could enhance AChE activity in the SDH and decrease [3H]-QNB binding sites; (2) Cap treating sciatice nerve could weaken AChE activity in the SDH and merease [3H]-QNB binding sites; (3) Cap treatment could inhibit or partially inhibit the actions of EA as above. The results indicated that ACh participated in the primary afferent of acupuncture information and might exist in Cap-sensitive neurons.     

Nervous regulation of the tone of the retractor penis muscle in the goat

The nervous control of the retractor penis muscle (rp) was investigated in the anaesthetized goat. Also, isolated field stimulated strips of the muscle were studied. The noradrenaline (NA) and acetylcholine (ACh) content of the rp was determined, and histochemistry for adrenergic and acetylcholinesterase (AChE) positive nerves was performed. The muscle exhibited spontaneous activity that persisted after section of all nerves. There was, however, also a tendency of the activity to follow the general vasomotor tone, which disappeared after section of the sympathetic chains. The excitatory adrenergic nerves which innervate the muscle come from the sympathetic chains and run along the pudendal, the hypogastric and the pelvic nerves. The rp has a dense network of adrenergic fibres and is very sensitive to excitatory adrenergic stimulation. It has a fairly large NA content, which is higher in old goats (5.95 +/- 0.42 micrograms g-1) than in young goats (2.87 +/- 0.78 micrograms g-1). Inhibitory non-adrenergic non-cholinergic (NANC) innervation reaches it via the pelvic and the hypogastric nerves. The maximum inhibitory response is reached at low frequencies (2-4 Hz). Cholinergic prejunctional inhibition of the excitatory response to sympathetic chain stimulation was effected by simultaneous stimulation of the hypogastric nerves. In vitro experiments confirmed the presence of endogenous cholinergic muscarinic suppression of the excitatory adrenergic neurotransmission. Significant amounts of ACh (0.81 +/- 0.18 micrograms g-1) are present in the muscle, and it contains strongly AChE positive nerve fibres and nerve cell bodies. It is concluded that the goat rp is innervated by sympathetic adrenergic excitatory nerves and parasympathetic NANC inhibitory nerves. It further has a direct sympathetic inhibitory NANC innervation, and an indirect inhibitory cholinergic innervation which at least in part is sympathetic.     

Interleukin 1beta and interleukin 6, but not tumor necrosis factor alpha, inhibit insulin-stimulated glycogen synthesis in rat hepatocytes

Recent evidence indicates that inflammatory cytokines are involved in changes of blood glucose concentrations and hepatic glucose metabolism in infectious diseases, including sepsis. However, little is known regarding how cytokines interact with glucoregulatory hormones such as insulin. The objective of the present study is to investigate if and how cytokines influence insulin-stimulated glycogen metabolism in the liver. Interleukin 1beta (IL-1beta) and interleukin 6 (IL-6) markedly inhibited the increase of glycogen deposition stimulated by insulin in primary rat hepatocyte cultures; however, tumor necrosis factor alpha had no effect. Labeling experiments revealed that both cytokines counteracted insulin action by decreasing [14C]-glucose incorporation into glycogen and by increasing [14C]-glycogen degradation. Furthermore, it was discovered that IL-1beta and IL-6 inhibited glycogen synthase activity and, in contrast, accelerated glycogen phosphorylase activity. In experiments with kinase inhibitors, serine/threonine kinase inhibitor K252a blocked IL-1beta- and IL-6-induced inhibitions of glycogen deposition, as well as glycogen synthase activity, whereas another kinase inhibitor staurosporine blocked only IL-6-induced inhibition. Tyrosine kinase inhibitor herbimycin A blocked only IL-1beta-induced inhibition. These results indicate that IL-1beta and IL-6 regulate insulin-stimulated glycogen synthesis through different pathways involving protein phosphorylation in hepatocytes. They may mediate the change of hepatic glucose metabolism under pathological and even physiological conditions by modifying insulin action in vivo.     

Tumour predisposition in mice heterozygous for a targeted mutation in Nf1

In this study the effects of administration of cortisone acetate (100 mg kg-1 body weight subcutaneously for 11 days) on distribution and cross-sectional area of different fibre types of rat skeletal muscles were investigated. Diaphragm, parasternal intercostal (PI), extensor digitorum longus (EDL) and soleus muscles were examined in cortisone treated animals (CA) in comparison with ad libitum controls (CTRL) and pair-fed (PF) controls. Four fibre types (I or slow and IIA, IIX, IIB or fast) were identified on the basis of their myosin heavy chain composition using a set of monoclonal antibodies. In CA rats the reduction of cross-sectional area was above 30% in IIX fibres of diaphragm, IIB fibres of PI and in all fast fibres of EDL. In all muscles slow fibres were spared from atrophy. Significant variations in fibre type distribution were found in the muscles of CA rats when compared to CTRL. The percentage of IIB fibres decreased in EDL, PI and diaphragm. This decrease was accompanied by an increase in the percentage of IIA fibres in the same muscles. No changes in the percentage of slow fibres and of fast IIX fibres were observed in EDL, PI and diaphragm of CA rats in comparison with CTRL. In soleus of CA rats the proportion of IIA fibres was lower than in CTRL. In EDL of PF rats atrophy of IIA fibres and changes in fibre type distribution were similar to those observed in CA rats.(ABSTRACT TRUNCATED AT 250 WORDS)     

Interleukin 1 beta, but not tumor necrosis factor, enhances neurogenic vasodilatation in the rat skin: involvement of nitric oxide

In phenobarbitone-anesthetized rats the effects of interleukin 1 beta (IL-1 beta) and tumor necrosis factors (TNFs) were examined on the capsaicin-induced increase of plantar cutaneous blood flow in the rat hind paw as measured by laser Doppler flowmetry. IL-1 beta (0.5-500 pg) or TNF alpha or TNF beta (50-500 pg) was injected subcutaneously into the left paws, while the right paws received vehicle (10 microL) only. IL-1 beta was without effect on blood flow by its own but dose dependently enhanced the hyperemia due to capsaicin (0.3 microgram). TNFs failed to enhance the capsaicin-induced vasodilatation although 5000 pg TNF alpha produced a transient increase of local blood flow. Indomethacin (10 mg/kg, i.p.) did not alter the capsaicin-induced vasodilatation but prevented IL-1 beta (50 pg) from augmenting the hyperemic response to capsaicin. Likewise, blockade of nitric oxide formation by NG-nitro-L-arginine methyl ester (L-NAME) failed to affect the capsaicin-evoked vasodilatation but abolished its amplification by IL-1 beta. Systemic pretreatment with a neurotoxic dose of capsaicin reduced the capsaicin-induced hyperemia and prevented the facilitatory effect of IL-1 beta. The hyperemia evoked by intraplantar calcitonin gene related peptide (0.038-3.8 ng) was not altered by IL-1 beta (50 pg). These data indicate that IL-1 beta but not TNF enhances the cutaneous hyperemic response to capsaicin. This proinflammatory action arises from sensitization of afferent nerve endings and depends on nitric oxide and cyclooxygenase products as essential intermediates.     

Developmentally regulated expression of interleukin-1 beta by peri-implantation conceptuses in swine

Interleukin-1 beta (IL-1 beta) is one of the critical inflammatory cytokines involved in many physiological processes. This study investigated the temporal expression of IL-1 beta in pig conceptuses. A human IL-1 beta cDNA probe and a anti-human IL-1 beta antibody were used to examine IL-1 beta gene and protein expression in pig conceptuses on days 11, 12, 13, 14, 15, 20, 30, 45, 60, 75, 90, 105 and 112 of pregnancy using Northern, Slot and Western blot analyses. A human cell line (A375.S2) was used to determine IL-1 activity in pig conceptuses. High levels of IL-1 beta mRNA were detected in days 11, 12 and 13 conceptuses. IL-1 beta protein was also detected in conceptuses on days 11, 12, 13, and 14, but not in conceptuses recovered after day 15 of pregnancy. IL-1 beta biological activity was demonstrated in days 11 and 12 conceptus homogenates, but not in homogenates of days 112 allantochorion. Low levels of IL-1 beta mRNA were detected by Northern blot analysis in Day 15 conceptuses, endometrium and myometrium only when poly(A+) RNA was used. The production of IL-1 beta by peri-implantation pig conceptuses was temporally associated with maternal recognition of pregnancy. The results suggest that conceptus IL-1 beta may be important for conceptus development and establishment of pregnancy.     

Interleukin 1 beta inhibits synaptic strength and long-term potentiation in the rat CA1 hippocampus

Cytokines such as interleukin-1 beta (IL-1 beta) are released in the nervous system following inflammation or infection. Recently, IL-1 beta was shown to enhance synaptic inhibitory mechanisms. We therefore investigated the effect of IL-1 beta superfusion on long-term potentiation (LTP), the cellular model of memory and learning, evoked in the CA1 region by tetanic stimulation of the stratum radiatum in the rat hippocampal slice. IL-1 beta (150 pM-1.5 nM) superfused 10 min before tetanic stimulation significantly reduced LTP of the slope of the population excitatory postsynaptic potential (pEPSP) and the population spike (PS) amplitude in CA1 in a concentration-dependent manner. IL-1 beta (1.5 nM) applied for 10 min 1 h before tetanus significantly inhibited LTP of the PS amplitude and pEPSP slope and reduced pEPSP and PS values before tetanus as well, although the PS returned to control values before tetanus. Heat-inactivated IL-1 beta had no effect on pre-tetanus pEPSP or PS values or the induction of LTP. These data demonstrate that IL-1 beta modulates synaptic potentials and reduces LTP. These findings have important implications for the role of IL-1 beta in neuronal disorders following infection, perhaps best exemplified by HIV-1-associated dementia.     

Effects of interleukin-1 beta on scanning electron microscopic appearance and thyroid peroxidase content of human thyrocytes in monolayer culture

Interleukin (IL-1), an inflammatory cytokine that is detected in the thyroid tissues of patients with autoimmune thyroiditis, is believed to be involved in the disease process. To clarify the role of IL-1 in the development of autoimmune thyroiditis, we investigated the effects of interleukin-1 beta (IL-1 beta) on the morphology of human thyrocytes in monolayer culture as well as the effect on thyroid peroxidase (TPO) content of these cells. Human normal thyrocytes were cultured with IL-1 beta for 4 days in the presence and absence of TSH. In morphologic studies, cultured cells were fixed for examination by scanning electron microscopy and for immunofluorescent staining of acting filaments. IL-1 produced striking morphologic changes in the cultured thyrocytes, including the cytoplasmic retraction and dissociation and/or depolymerization of actin filaments. These changes were unrelated to TSH stimulation. For detection of TPO, cultured cells were stained by an immunofluorescent technique and analyzed by fluorescence photometry. IL-1 reduced the TPO content and inhibited the TSH-induced increase in TPO in a concentration-dependent manner. These morphological changes and the reduction in TPO content of cultured thyrocytes suggest that IL-1 modulates the pathophysiology of autoimmune thyroiditis.     

Apolipoprotein E and its alleles in healthy subjects and in atherosclerosis

To examine responses of natural killer cell activity (NKCA) to interleukin-1 beta (IL-1 beta) during pregnancy, we determined splenic NKCA as well as blood and brain indicators in virgin and pregnant rats (14 or 21 days gestation) with intracerebroventricular (i.c.v.) administration of IL-1 beta. NKCA was reduced and blood beta-endorphin (beta EP) was increased with the progress of pregnancy. I.c.v. administration of IL-1 beta reduced NKCA and corticotropin-releasing hormone (CRH) in the median eminence (ME), and increased beta EP in virgin rats, but did not change any parameters in pregnant rats with 21 days gestation. These data suggest that the immunosuppressive effect of central administration of IL-1 beta is blocked by pregnancy. CRH in the ME and opioid system seem to be involved in the inhibitory effect of pregnancy on IL-1 beta-induced immunosuppression.     

Arrested rearrangement of TCR V beta genes in thymocytes from children with X-linked severe combined immunodeficiency disease

Human X-linked severe combined immunodeficiency disease (SCID) is an immunodeficiency disorder in which T cell development is arrested in the thymic cortex. B lymphocytes in children with X-linked SCID seem to differentiate normally. X-linked SCID is associated with a mutation in the gene that encodes the IL-2R gamma-chain. Because TCR-beta gene recombination is a pivotal initial event in T lymphocyte ontogeny within the thymus, we hypothesized that a failure to express normal IL-2R gamma could lead to impaired TCR-beta gene recombination in early thymic development. PCR was used to determine the status of TCR-beta gene-segment rearrangements in thymic DNA that had been obtained from children with X-linked SCID. The initial step in TCR-beta gene rearrangement, that of D beta to J beta recombination, was readily detected in all thymus samples from children with X-linked SCID; in contrast, V beta to DJ beta gene rearrangements were undetectable in the same samples. Both D beta to J beta and V beta to DJ beta TCR genes were rearranged in the thymic tissues obtained from immunologically normal children. We conclude that TCR beta-chain gene rearrangement is arrested in children with X-linked SCID. Our results suggest a causative relationship between the failure of TCR beta-chain gene rearrangements to proceed beyond DJ beta rearrangements and the production of a nonfunctional IL-2R gamma-chain.     

Flt3 ligand plus IL-7 supports the expansion of murine thymic B cell progenitors that can mature intrathymically

Flt3 ligand (flt3L) has potent effects on hemopoietic progenitors, dendritic cells, and B lymphopoiesis. We have investigated the effects of flt3L on intrathymic precursors. The addition of flt3L + IL-7 to lobe submersion cultures of murine fetal thymic lobes resulted in the expansion of an immature population of Thy-1(low), CD44(high), HSA(high) cells. This population contained cells with precursor activity, as determined by their capacity to repopulate deoxyguanosine-treated fetal thymic lobes. Upon reentry to the thymic lobe, flt3L + IL-7-cultured Thy-1(low), CD44(high), HSA(high) cells underwent expansion and differentiation into B cells. Two weeks after fetal thymic organ culture following thymic lobe reconstitution, intrathymic cells were Thy-1-, B220+, and a subset was sIgM+. The intrathymic B cells shared features of adult thymic B cells, including CD5 expression and proliferative responses to IL-4 + IL-5 + CD40 ligand, but not to LPS or soluble anti-IgM. Ig production was noted upon stimulation with IL-4 + IL-5 + LPS and IL-4 + IL-5 + CD40 ligand. In conclusion, we have demonstrated that flt3L + IL-7 supports the expansion of a subset of progenitors present in the fetal thymus. The cultured progenitors can repopulate a fetal thymic lobe and develop into mature functional B cells, demonstrating that the fetal thymus is able to support B cell as well as T cell development.