The aim of this work was to study effects of ketotifen fumarate (KF) on prevention of tissue damage in testes of rats with experimental autoimmune orchitis (EAO) and on the contralateral testis in a model of prolonged testicular cord torsion (TCT). Rats with EAO or TCT were injected intraperitoneally once daily with KF or saline solution (vehicle group). Incidence and severity of testicular damage were evaluated by histopathology using an EAO score or a Johnsen score. Mast cells (MC) were identified by histochemistry and quantified. In EAO model, KF significantly reduced severity of histopathological testicular damage compared to rats in the vehicle group. KF also reduced the number of testicular MC compared to vehicle group. Similarly, in TCT model, multifocal damage of the contralateral testis was observed 30 days after testicular torsion characterized by sloughing of the germinal epithelium, seminiferous tubule atrophy, and interstitial edema. Focal signs of inflammation and fibrosis of seminiferous tubular walls were also observed. In contrast, sections of contralateral testis of rats injected with KF and killed 30 days after surgery showed normal histological features. A significant decrease in the number of MC was observed in rats treated with KF compared to untreated animals. In conclusion, we demonstrated that treatment with KF reduced testicular inflammatory process and MC infiltrates in both EAO and TCT models. The results suggest a promising treatment for infertile male patients with testicular pathologies associated with inflammation and germ cell loss.
Animals ; Autoimmune Diseases/pathology* ; Cell Count ; Epididymis/pathology* ; Epididymitis/pathology* ; Histamine H1 Antagonists/pharmacology* ; Hypersensitivity, Delayed ; Immunity, Cellular/drug effects* ; Ketotifen/pharmacology* ; Male ; Mast Cells/pathology* ; Orchitis/pathology* ; Rats ; Severity of Illness Index ; Spermatic Cord Torsion/pathology* ; Testis/pathology* ; Vaccination

Cyproheptadine (CPH), a first-generation antihistamine, enhances the delayed rectifier outward K current (I) in mouse cortical neurons through a sigma-1 receptor-mediated protein kinase A pathway. In this study, we aimed to determine the effects of CPH on neuronal excitability in current-clamped pyramidal neurons in mouse medial prefrontal cortex slices. CPH (10 µmol/L) significantly reduced the current density required to generate action potentials (APs) and increased the instantaneous frequency evoked by a depolarizing current. CPH also depolarized the resting membrane potential (RMP), decreased the delay time to elicit an AP, and reduced the spike threshold potential. This effect of CPH was mimicked by a sigma-1 receptor agonist and eliminated by an antagonist. Application of tetraethylammonium (TEA) to block I channels hyperpolarized the RMP and reduced the instantaneous frequency of APs. TEA eliminated the effects of CPH on AP frequency and delay time, but had no effect on spike threshold or RMP. The current-voltage relationship showed that CPH increased the membrane depolarization in response to positive current pulses and hyperpolarization in response to negative current pulses, suggesting that other types of membrane ion channels might also be affected by CPH. These results suggest that CPH increases the excitability of medial prefrontal cortex neurons by regulating TEA-sensitive I channels as well as other TEA-insensitive K channels, probably I and inward-rectifier Kir channels. This effect of CPH may explain its apparent clinical efficacy as an antidepressant and antipsychotic.
Animals ; Cyproheptadine ; pharmacology ; Female ; Histamine H1 Antagonists ; pharmacology ; Membrane Potentials ; drug effects ; physiology ; Mice, Inbred C57BL ; Patch-Clamp Techniques ; Potassium Channel Blockers ; pharmacology ; Potassium Channels ; metabolism ; Prefrontal Cortex ; drug effects ; physiology ; Pyramidal Cells ; drug effects ; physiology ; Receptors, sigma ; agonists ; metabolism ; Tetraethylammonium ; pharmacology ; Tissue Culture Techniques

To investigate the effects of neuronal histamine on spatial memory acquisition impairment in rats with pentylenetetrazole-kindling epilepsy, and to explore its mechanisms.A subconvulsive dose of pentylenetetrazole (35 mg/kg) was intraperitoneally injected in rats every 48 h to induce chemical kindling until fully kindled. Morris water maze was used to measure the spatial memory acquisition of the rats one week after fully pentylenetetrazole-kindled, and the histamine contents in different brain areas were measured spectrofluorometrically. Different dosages of hitidine (the precursor of histamine), pyrilamine (H1 receptor antagonist), and zolantidine (H2 receptor antagonist) were intraperitoneally injected, and their effects on spatial memory acquisition of the rats were observed.Compared with control group, escape latencies were significantly prolonged on Morris water maze training day 2 and day 3 in pentylenetetrazole-kindling epilepsy rats (all<0.05); and the histamine contents in hippocampus, thalamus and hypothalamus were decreased significantly (all<0.05). Escape latencies were markedly shortened on day 3 by intraperitoneally injected with histidine 500 mg/kg, and on day 2 and day 3 by intraperitoneally injected with histidine 1000 mg/kg in pentylenetetrazole-kindling epilepsy rats (all<0.05). The protection of histidine was reversed by zolantidine (10 and 20 mg/kg), but not by pyrilamine.Neuronal histamine can improve the spatial memory acquisition impairment in rats with pentylenetetrazole-kindling epilepsy, and the activation of H2 receptors is possibly involved in the protective effects of histamine.
Animals ; Benzothiazoles ; pharmacology ; Brain Chemistry ; drug effects ; Epilepsy ; chemically induced ; complications ; Hippocampus ; chemistry ; Histamine H1 Antagonists ; pharmacology ; Histamine H2 Antagonists ; pharmacology ; Histidine ; pharmacology ; Hypothalamus ; chemistry ; Kindling, Neurologic ; physiology ; Memory Disorders ; drug therapy ; etiology ; Pentylenetetrazole ; Phenoxypropanolamines ; pharmacology ; Piperidines ; pharmacology ; Pyrilamine ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptors, Histamine H2 ; drug effects ; physiology ; Spatial Memory ; drug effects ; Spectrometry, Fluorescence ; Thalamus ; chemistry

OBJECTIVE: To investigate the changes of leukotriene D4 (LTD4) in nasal discharge and plasma of patients with persistent allergic rhinitis (AR) and the effects of antihistamine. METHOD: The investigation was a prospective, randomized controlled trial. Forty AR patients (group C) were divided randomly into two subgroup. One group received oral antihistamine 10 mg everyday for one week (group CA) and another group received no loratadine tablets 10 mg everyday for one week (group CB). Fifteen age matched healthy (group D) people were enrolled as control. The level of LTD4 and interleukin-5 (IL-5) in both nasal discharge and plasma by using enzyme linked immunosorbent assay (ELISA) and enzyme immunoassay (EIA), cell counts and cell differentials in nasal discharge, were measured before and after three month. The clinical symptom and life quality scores of group C were also investigated. RESULT: The concentrations of LTD4 in nasal discharge [(794 +/- 305) pg] and plasma [(5219 +/- those in group D [(347 +/- 169) pg, (2283 +/- 489) ng/L, all P 1185) ng/L] in group C were significantly higher than those in group D [(347 +/- 169) pg, (2283 +/- 489) ng/L, all P < 0.05]. The level of LTD4 in nasal discharge was positively correlated with the percentage of neutrophil (r = 0.453, P < 0.05) and IL-5 (r = 0.364, P < 0.05). The pre- and post-therapy concentrations of nasal discharge and plasma in group CA were (812 +/- 1592) pg, (657 +/- 495) pg and (5422 +/- 935) ng/L, (4589 +/- 1057) ng/L respectively; While in group CB the concentrations were (776 +/- 227) pg, (860 +/- 194) pg and (5074 +/- 1850) ng/L, (6063 +/- 450) ng/L, respectively. There were no significant difference either in the level of LTD4 in nasal discharge or in plasma in both groups (all P > 0.05). CONCLUSION The results suggested that LTD4 was involved in airway inflammation in AR. Antihistamine was not effective enough in decreasing the levels of LTD4 in both nasal discharge and plasma of AR patients.
Adult ; Anti-Allergic Agents ; pharmacology ; Bodily Secretions ; chemistry ; Female ; Histamine H1 Antagonists ; pharmacology ; Humans ; Leukotriene Antagonists ; therapeutic use ; Leukotriene D4 ; analysis ; blood ; metabolism ; Male ; Middle Aged ; Plasma ; chemistry ; Prospective Studies ; Rhinitis, Allergic, Perennial ; blood ; drug therapy ; metabolism

The purpose of this study was to determine the effectiveness of antihistamine therapy for withdrawal movements caused by rocuronium injection. One hundred seventy one ASA I-II adults undergoing elective surgery were randomly assigned to one of two groups. Patients in the control group (Group C) were premedicated with 2 mL normal saline, and those in the antihistamine group (Group A) were pre-medicated with 2 mL (45.5 mg) pheniramine maleate. After the administration of thiopental sodium 5 mg/kg, rocuronium 0.6 mg/kg was injected. Withdrawal movements were assessed using a four-grade scale. The administration of antihistamine reveals lower grade of withdrawal movement after rocuronium injection.
Adult ; Androstanols/*administration & dosage/adverse effects ; Anesthetics, Intravenous/administration & dosage ; Double-Blind Method ; Female ; Histamine H1 Antagonists/*pharmacology ; Humans ; Incidence ; Injections, Intravenous ; Male ; Middle Aged ; Movement/drug effects/physiology ; Neuromuscular Nondepolarizing Agents/*administration & dosage/adverse effects ; Pain/chemically induced ; Pain Measurement ; Pheniramine/*pharmacology ; Thiopental/administration & dosage

OBJECTIVE: To compare the efficacy and safety of histamine H1 receptor antagonist loratadine with Leukotriene receptor antagonist Ibudilast in steroid resistant allergic rhinitis in a randomized controlled clinical trial. METHOD: Thirty-five cases were treated by Ibudilast, and 34 cases by loratadine. Score system was used to compare the therapeutic effect of these two drugs on clinical symptoms and signs. RESULT: Ibudilast shows a better curative effect than loratadine in the improvement of the total scores on clinical symptom and signs(P<0.05). Scores of symptoms and signs in Ibudilast group after 3, 7, 14 days decreased significantly by means of square analysis of single factor (P<0.01). No complication was observed. CONCLUSION Ibudilast can effectively alleviate the clinical symptoms and signs of steroid resistant allergic rhinitis with confirmed efficacy and safety, thus is recommended in steroid resistant allergic rhinitis. Increased doses or prolonged treatment of steroid is inappropriate.
Adolescent ; Adult ; Aged ; Anti-Allergic Agents ; therapeutic use ; Female ; Histamine H1 Antagonists, Non-Sedating ; therapeutic use ; Humans ; Leukotriene Antagonists ; therapeutic use ; Loratadine ; therapeutic use ; Male ; Middle Aged ; Pyridines ; therapeutic use ; Rhinitis, Allergic, Perennial ; drug therapy ; Rhinitis, Allergic, Seasonal ; drug therapy ; Steroids ; pharmacology ; Young Adult

Histamine H1 Antagonists ; pharmacology ; Humans

To investigate the effect of cetirizine hydrochloride on the expression of neurokinin 1 receptor (NK-1R) and cytokines production induced by substance P (SP) in HaCaT cells (a human epidermal keratinocyte cell line) and dermal fibroblasts. The effect of cetirizine on the expression of NK-1R protein was detected by flow cytometry and Western blotting analysis. The modulation of cetirizine on the production of interferon (IFN)-gamma, interleukin (IL)-1beta, IL-6 and IL-8 in HaCaT cells and fibroblasts was measured by ELISA. The results showed that cetirizine significantly inhibited the expression of NK-1R in HaCaT cells and fibroblasts. SP induced the production of IFN-gamma, IL-1beta and IL-8 in both cell types. Cetirizine 1-100 micromol x L(-1) inhibited SP-induced IL-1beta and IL-8 production in HaCaT cells and fibroblasts, while had no effect on the production of IFN-gamma in both cells. Both SP and cetirizine had no effect on the secretion of IL-6 in HaCaT cells and fibroblasts. These findings suggest that cetirizine may be involved in the treatment of SP-induced skin inflammation by inhibiting the expression of substance P receptor and regulation the production of IL-1beta and IL-8 in epidermal keratinocyte and dermal fibroblasts.
Anti-Allergic Agents ; pharmacology ; Cell Line ; Cetirizine ; pharmacology ; Fibroblasts ; cytology ; metabolism ; Histamine H1 Antagonists, Non-Sedating ; pharmacology ; Humans ; Interferon-gamma ; metabolism ; Interleukin-1beta ; metabolism ; Interleukin-8 ; metabolism ; Keratinocytes ; cytology ; metabolism ; Receptors, Neurokinin-1 ; metabolism ; Substance P ; pharmacology

The present study was carried out to determine the role of histamine H(1) and H(2) receptors in the generation of basic respiratory rhythm. Neonatal (aged 0-3 d) Sprague-Dawley rats of either sex were used. The medulla oblongata slice containing the medial region of the nucleus retrofacialis (mNRF) and the hypoglossal nerve rootlets was prepared and the surgical procedure was performed in the modified Kreb's solution (MKS) with continuous carbogen (95% O(2) and 5% CO(2)), and ended in 3 min. Respiratory rhythmical discharge activity (RRDA) of the rootlets of hypoglossal nerve was recorded by suction electrode. Thirty medulla oblongata slice preparations were divided into 5 groups. In groups I, II and III, histamine (5 μmol/L), H(1) receptor specific antagonist pyrilamine (10 μmol/L) and H(2) receptor specific antagonist cimetidine (5 μmol/L) was added into the perfusion solution for 15 min separately. In group IV, after application of histamine for 15 min, additional pyrilamine was added into the perfusion for another 15 min. In group V, after application of histamine for 15 min, additional cimetidine was added into the perfusion for another 15 min. The discharges of the roots of hypoglossal nerve were recorded. Signals were amplified and band-pass filtered (100-3.3 kHz). Data were sampled (1-10 kHz) and stored in the computer via BL-420 biological signal processing system. Our results showed that histamine significantly decreased the respiratory cycle (RC) and expiratory time (TE), but changes of integral amplitude (IA) and inspiratory time (TI) were not statistically significant. Pyrilamine induced significant increases in RC and TE, but changes of TI and IA were not statistically significant. Cimetidine had no effects on RC, TE, TI and IA of RRDA. The effect of histamine on the respiratory rhythm was reversed by additional application of pyrilamine but not cimetidine. Taken together, with the results mentioned above, histamine H(1) receptors but not H(2) receptors may play an important role in the modulation of RRDA in the medulla oblongata slice preparation of neonatal rats.
Animals ; Animals, Newborn ; Cimetidine ; pharmacology ; Female ; Histamine ; pharmacology ; Histamine H1 Antagonists ; pharmacology ; Histamine H2 Antagonists ; pharmacology ; Hypoglossal Nerve ; physiology ; In Vitro Techniques ; Male ; Medulla Oblongata ; physiology ; Pyrilamine ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptors, Histamine H1 ; physiology ; Receptors, Histamine H2 ; physiology ; Respiration

AIMTo determine the effect of histamine on ischemia-induced cellular edema and viability reduction in rat hippocampal slices, and the involved subtypes of histamine receptor in this effect.

METHODSIn vitro ischemic injury of hippocampal slices was induced by oxygen-glucose deprivation (OGD). The slice injury was determined by real-timely measuring the changes of light transmittance (LT) for the cellular edema in CA1 region of the hippocampal slice, and by detecting the product of 2, 3, 5-triphenyltetrazolium chloride (TTC), formazan, for the slice viability. The effect of histamine at various concentrations on the slice injury was observed, and the blockage by antagonists of histamine receptors was also investigated.

RESULTSHistamine (0.01-10 micromol x L(-1)) inhibited the peak value of LT during OGD in hippocampal slices and improved the reduced viability after OGD. Diphenhydramine (0.1-10 micromol x L(-1)), an H1 receptor antagonist, did not affect the effect of histamine, while cimetidine (0.1-10 micromol x L(-1)), an H2 receptor antagonist, partly abolished the protective effect of histamine.

CONCLUSIONHistamine protects hippocampal slices against ischemia-induced cellular edema and viability reduction; this effect might be mediated via, at least partly, H2 receptor.

Animals ; Cell Hypoxia ; Cell Survival ; drug effects ; Cimetidine ; pharmacology ; Diphenhydramine ; pharmacology ; Formazans ; metabolism ; Glucose ; deficiency ; Hippocampus ; drug effects ; metabolism ; pathology ; Histamine ; pharmacology ; Histamine H1 Antagonists ; pharmacology ; Histamine H2 Antagonists ; pharmacology ; Male ; Neuroprotective Agents ; pharmacology ; Rats ; Rats, Sprague-Dawley