Lipopolysaccharide (LPS)-induced inflammatory stress activates the hypothalamus-pituitary-adrenal (HPA) function. Interleukin-I (IL-1) is one of the key factors during this event; however, the mechanisms mediating IL-1 stimulation of HPA axis are still unclear. The present study evaluated the possible involvement of gamma-aminobutyric acid (GABA) in LPS-induced activation of HPA axis in adult male rats. In addition, the possible existence of diurnal changes of LPS-induced HPA axis activity was also investigated. Bicuculline (0.8 mg/kg BW), a GABA-A receptor antagonist and GABA (1 g/kg BW) were intraperitoneally (ip) injected 15 min before LPS (2 mg/kg BW, ip) or recombinant human IL-1 alpha (microgram/rat) administration in intact rats. Control animals received an equivalent volume of 0.9% saline. Rats were sacrificed at 60 min or 90 min after LPS, or IL-1 alpha or saline injection. Plasma corticosterone levels were measured by radioimmunoassay. Results showed that pretreatment with bicuculline enhanced both LPS- and IL-1-induced corticosterone secretion; while pretreatment with GABA significantly reduced the LPS-stimulated corticosterone release (p < 0.05, vs LPS alone). The effect is dependent on the time of sampling and such effect of bicuculline or GABA was not observed when rats were stimulated in the evening. In addition, the maximal changes of plasma corticosterone following LPS administration in the evening were significantly lower than in the morning (p < 0.01). The present study provides evidence that GABA is involved, at least in part, in the neuroendocrine regulation of LPS/interleukin-1a-induced corticosterone secretion via GABA-A receptor in rats. In addition, the response of plasma corticosterone to LPS has a diurnal variation, which corresponds to a diurnal change of GABAergic modulation of the immunoneuroendocrine response.

1992-10-01·American journal of obstetrics and gynecology1区 · 医学

The natural interleukin-1 receptor antagonist prevents interleukin-l-induced preterm delivery in mice

1区 · 医学

Article

作者: Roberto Romero ; Boris Tartakovsky

OBJECTIVES:

Interleukin-1 has been implicated in the mechanisms responsible for preterm parturition in the setting of intrauterine infection. This cytokine is produced by human decidua, stimulates prostaglandin production by intrauterine tissues, and induces preterm parturition in mice. The purpose of this study was to determine whether pretreatment with the natural interleukin-1 receptor antagonist can block interleukin-1-induced preterm parturition in mice.

STUDY DESIGN:

Balb/CJ female mice impregnated by B6D2 F-1 male mice were randomly allocated to one of the following treatment groups: (1) saline solution (n = 15), (2) human recombinant interleukin-1 alpha or human recombinant interleukin-1 beta (n = 12), (3) human recombinant interleukin-1 receptor antagonist (n = 13), and (4) human recombinant interleukin-1 receptor antagonist plus human recombinant interleukin-1 (n = 24).

RESULTS:

An interleukin-1 dose of 10 micrograms per mouse induced preterm parturition in all cases. Pretreatment with interleukin-1 receptor antagonist (dose 1 mg per animal) prevented interleukin-1-induced preterm parturition. Interleukin-1 receptor antagonist administration was not associated with demonstrable side effects including behavioral changes, vaginal bleeding, duration of pregnancy, and pregnancy outcome.

CONCLUSION:

Our results suggest that interleukin-1-induced preterm delivery in mice is mediated by the interleukin-1 receptor.

1990-12-01·Endocrinology2区 · 医学

Interleukin-1 Receptors in Mouse Brain:Characterization and Neuronal Localization

2区 · 医学

Article

作者: Takao, Toshihiro ; Mitchell, W. Mark ; Tracey, Daniel E. ; De Souza, Errol B.

The cytokine interleukin-1 (IL-1) has a variety of effects in brain, including induction of fever, alteration of slow wave sleep, and alteration of neuroendocrine activity. To examine the potential sites of action of IL-1 in brain, we used iodine-125-labeled recombinant human interleukin-1 [( 125I]IL-1) to identify and characterize IL-1 receptors in crude membrane preparations of mouse (C57BL/6) hippocampus and to study the distribution of IL-1-binding sites in brain using autoradiography. In preliminary homogenate binding and autoradiographic studies, [125I]IL-1 alpha showed significantly higher specific binding than [125I]IL-1 beta. Thus, [125I]IL-1 alpha was used in all subsequent assays. The binding of [125I]IL-1 alpha was linear over a broad range of membrane protein concentrations, saturable, reversible, and of high affinity, with an equilibrium dissociation constant value of 114 +/- 35 pM and a maximum number of binding sites of 2.5 +/- 0.4 fmol/mg protein. In competition studies, recombinant human IL-1 alpha, recombinant human IL-1 beta, and a weak IL-1 beta analog. IL-1 beta +, inhibited [125I]IL-1 alpha binding to mouse hippocampus in parallel with their relative bioactivities in the T-cell comitogenesis assay, with inhibitory binding affinity constants of 55 +/- 18, 76 +/- 20, and 2940 +/- 742 pM, respectively; rat/human CRF and human tumor necrosis factor showed no effect on [125I]IL-1 alpha binding. Autoradiographic localization studies revealed very low densities of [125I]IL-1 alpha-binding sites throughout the brain, with highest densities present in the molecular and granular layers of the dentate gyrus of the hippocampus and in the choroid plexus. Quinolinic acid lesion studies demonstrated that the [125I]IL-1 alpha-binding sites in the hippocampus were localized to intrinsic neurons. After hypophysectomy, homogenate binding and autoradiographic studies showed that there was no apparent change in the relative density of IL-1 receptors in the hippocampus. The identification of IL-1 receptors in brain with characteristics similar to IL-1 receptors in immune and neuroendocrine tissues provides further support for a physiological role for IL-1 to regulate central nervous system activity.

100 项与 Recombinant human alpha-1 antitrypsin(LFB Biotechnologies SASU) 相关的药物交易

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