Most diabetic patients experience diabetic mellitus (DM) urinary bladder dysfunction. A number of studies evaluate bladder smooth muscle contraction in DM. In this study, we evaluated the change of bladder smooth muscle contraction between normal rats and DM rats. Furthermore, we used pharmacological inhibitors to determine the differences in the signaling pathways between normal and DM rats. Rats in the DM group received an intraperitoneal injection of 65 mg/kg streptozotocin and measured blood glucose level after 14 days to confirm DM. Bladder smooth muscle contraction was induced using acetylcholine (ACh, 10⁻⁴ M). The materials such as, atropine (a muscarinic receptor antagonist), U73122 (a phospholipase C inhibitor), DPCPX (an adenosine A1 receptor antagonist), udenafil (a PDE5 inhibitor), prazosin (an α₁-receptor antagonist), papaverine (a smooth muscle relaxant), verapamil (a calcium channel blocker), and chelerythrine (a protein kinase C inhibitor) were pre-treated in bladder smooth muscle. We found that the DM rats had lower bladder smooth muscle contractility than normal rats. When prazosin, udenafil, verapamil, and U73122 were pre-treated, there were significant differences between normal and DM rats. Taken together, it was concluded that the change of intracellular Ca²⁺ release mediated by PLC/IP3 and PDE5 activity were responsible for decreased bladder smooth muscle contractility in DM rats.
Acetylcholine ; Animals ; Atropine ; Blood Glucose ; Calcium Channels ; Humans ; Injections, Intraperitoneal ; Muscle, Smooth* ; Papaverine ; Prazosin ; Protein Kinase C ; Rats* ; Receptor, Adenosine A1 ; Receptors, Muscarinic ; Streptozocin ; Type C Phospholipases ; Urinary Bladder* ; Verapamil

Luteolin, a widespread flavonoid, has been known to have neuroprotective activity against various neurologic diseases such as epilepsy, and Alzheimer’s disease. However, little information is available regarding the hypnotic effect of luteolin. In this study, we evaluated the hypnotic effect of luteolin and its underlying mechanism. In pentobarbital-induced sleeping mice model, luteolin (1, and 3 mg/kg, p.o.) decreased sleep latency and increased the total sleep time. Through electroencephalogram (EEG) and electromyogram (EMG) recording, we demonstrated that luteolin increased non-rapid eye movement (NREM) sleep time and decreased wake time. To evaluate the underlying mechanism, we examined the effects of various pharmacological antagonists on the hypnotic effect of luteolin. The hypnotic effect of 3 mg/kg of luteolin was not affected by flumazenil, a GABAA receptor-benzodiazepine (GABAAR-BDZ) binding site antagonist, and bicuculine, a GABAAR-GABA binding site antagonist. On the other hand, the hypnotic effect of 3 mg/kg of luteolin was almost completely blocked by caffeine, an antagonist for both adenosine A1 and A2A receptor (A1R and A2AR), 8-Cyclopentyl-1,3-dipropylxanthine (DPCPX), an A1R antagonist, and SCH-58261, an A2AR antagonist. From the binding affinity assay, we have found that luteolin significantly binds to not only A1R but also A2AR with IC₅₀ of 1.19, 0.84 μg/kg, respectively. However, luteolin did not bind to either BDZ-receptor or GABAAR. From these results, it has been suggested that luteolin has hypnotic efficacy through A1R and A2AR binding.
Adenosine ; Animals ; Binding Sites ; Caffeine ; Electroencephalography ; Epilepsy ; Eye Movements ; Flumazenil ; Hand ; Hypnotics and Sedatives ; Luteolin ; Mice ; Receptor, Adenosine A1 ; Receptor, Adenosine A2A ; Sleep Initiation and Maintenance Disorders

BACKGROUND: Several types of receptors are found at neuromuscular presynaptic membranes. Presynaptic inhibitory A1 and facilitatory A2A receptors mediate different modulatory functions on acetylcholine release. This study investigated whether adenosine A1 receptor agonist contributes to the first twitch tension (T1) of train-of-four (TOF) stimulation depression and TOF fade during rocuronium-induced neuromuscular blockade, and sugammadex-induced recovery. METHODS: Phrenic nerve-diaphragm tissues were obtained from 30 adult Sprague-Dawley rats. Each tissue specimen was randomly allocated to either control group or 2-chloroadenosine (CADO, 10 μM) group. One hour of reaction time was allowed before initiating main experimental data collection. Loading and boost doses of rocuronium were sequentially administered until > 95% depression of the T1 was achieved. After confirming that there was no T1 twitch tension response, 15 min of resting time was allowed, after which sugammadex was administered. Recovery profiles (T1, TOF ratio [TOFR], and recovery index) were collected for 1 h and compared between groups. RESULTS: There were statistically significant differences on amount of rocuronium (actually used during experiment), TOFR changes during concentration-response of rocuronium (P = 0.04), and recovery profiles (P < 0.01) of CADO group comparing with the control group. However, at the initial phase of this experiment, dose-response of rocuronium in each group demonstrated no statistically significant differences (P = 0.12). CONCLUSIONS: The adenosine A1 receptor agonist (CADO) influenced the TOFR and the recovery profile. After activating adenosine receptor, sugammadex-induced recovery from rocuronium-induced neuromuscular block was delayed.
2-Chloroadenosine ; Acetylcholine ; Adenosine* ; Adult ; Data Collection ; Depression ; Humans ; Membranes ; Neuromuscular Blockade* ; Neuromuscular Junction ; Neuromuscular Nondepolarizing Agents ; Rats, Sprague-Dawley ; Reaction Time ; Receptor, Adenosine A1 ; Receptors, Purinergic P1*

OBJECTIVETo observe whether adenosine Al receptor (Al R) mediated neuroprotection of Shenmai Injection (SI) on rat cerebral ischemia/reperfusion (I/R) injury.

METHODSThe focal cerebral I/R model was established by middle cerebral artery occlusion (MCAO). Totally 60 successfully modeled rats was divided into 5 groups according to randomized block principle, i.e., the model group, the SI group, the SI + AlR antagonist (1,3-dipropyl-8-cyclopentylxanthine, DPCPX) group, the AlR antagonist control group, and the dimethyl sulfoxide (DMSO) control group, 12 in each group. Besides, a sham-operation group was set up (n =12). SI at 15 mL/kg was peritoneally injected to mice in the SI group immediately after cerebral I/R. Equal volume of normal saline was injected to mice in the model group and the sham-operation group. DPCPX at 1 mg/mL was peritoneally injected to mice in the Al R antagonist control group 30 min before peritoneal injecting SI. DPCPX at 1 mg/kg and DMSO at 1 mL/kg were peritoneally injected to mice in the AlR antagonist control group and the DMSO control group 30 min immediately before cerebral I/R. Rats' neurobehavioral scores were assessed after 24 h reperfusion. The volume of cerebral infarction and Bcl-2 protein expression of cerebral infarction penumbra were also detected. Results Compared with the sham-operation group, neurobehavioral scores, the volume of cerebral infarction, and Bcl-2 protein expression increased (all P <0. 05). Compared with the model group, neurobehavioral scores and the volume of cerebral infarction obviously decreased, but Bcl-2 protein expression increased in the SI group (all P <0. 05). Compared with the SI group, neurobehavioral scores increased, the volume of cerebral infarction was obviously enlarged, and Bcl-2 protein expression was obviously reduced in the A1R antagonist control group (all P <0. 05).

CONCLUSIONSSI's neurobehavioral scores could be partially reversed in the Al R antagonist control group, the volume of cerebral infarction and Bcl-2 protein expression improved. AlR might possibly meditate neuroprotection of SI on MACO mire

Adenosine ; Animals ; Brain Ischemia ; drug therapy ; Drug Combinations ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Infarction, Middle Cerebral Artery ; Mice ; Neuroprotection ; physiology ; Neuroprotective Agents ; pharmacology ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Receptor, Adenosine A1 ; metabolism ; Reperfusion Injury ; drug therapy ; Xanthines

Adenosine receptors (AR) play an important role in the regulation processes for body temperature and vigilance states. During our previous studies, we noticed that aminophylline (a non-selective, blood-brain-barrier penetrably AR antagonist) could attenuate the effects of YZG-330 [(2R,3S,4R,5R)-2-(hydroxymethyl-5-(6-(((R)-1-phenylpropyl)amino)-9H-purin-9-yl)tetrahydrofuran-3, 4-diol] on lowering the body temperature. Hereby, we focused ourselves on the character of thermal regulation effect of YZG-330 in mice and tried to specify the receptor subtype via giving typical adenosine receptor antagonists. The results showed that both of the magnitude and lasting time of the effect that YZG-330 played on decreasing body temperature are in a dose-dependent manner: within the next 3 hour after intragastric administration (ig) of 0.25, 1 or 4 mg . kg-1 YZG-330, the extreme values on body temperature decreasing were (1.2 ± 0.3) °C, (3.6 ± 0.4) °C (P<0.001) and (7.4±0.5) °C (P<0.001), separately; whereas the duration that body temperature below 34 °C were 0, (10±5) and (153±4) min, separately. Adenosine A1 receptor (A1R) antagonist (DPCPX) could effectively reverse YZG-330's effect on decreasing body temperature, with intraperitoneal administration of DPCPX (5 mg . kg-1) 20 min prior than YZG-330 (4 mg.kg-1, ig), the extreme value on body temperature decreasing was (3.5 ± 0.7) °C (P<0.001), the duration that body temperature below 34 °C was (8±6) min (P<0.001). However, adenosine A2a receptor antagonist, SCH-58261, did not show any influence on the effects of YZG-330 at all. Combined with the fact that 8-SPT (a non-selective, blood-brain-barrier impenetrably AR antagonist) did not reverse the effect of YZG-330, we come to the conclusion that central-adenosine A, receptor plays a significant role on the thermal regulation effect of YZG-330.
Adenosine ; analogs & derivatives ; pharmacology ; Adenosine A1 Receptor Antagonists ; pharmacology ; Animals ; Body Temperature Regulation ; drug effects ; Mice ; Pyrimidines ; pharmacology ; Receptor, Adenosine A1 ; physiology ; Triazoles ; pharmacology ; Xanthines ; pharmacology

OBJECTIVETo study the effects of caffeine citrate on myelin basic protein (MBP) expression in the cerebral white matter of neonatal rats with hypoxic-ischemic brain damage (HIBD) and the related mechanism.

METHODSForty-eight seven-day-old Sprague-Dawley neonatal rats were randomly assigned to 3 groups: sham operation (n=16), HIBD (n=16) and HIBD+caffeine citrate (n=16). The rats in the HIBD and HIBD+caffeine citrate groups were subjected to left common carotid artery ligation, and then were exposed to 80 mL/L oxygen and 920 mL/L nitrogen for 2 hours to induce HIBD. The rats in the sham operation group were only subjected to a sham operation, without the left common carotid artery ligation or hypoxia exposure. Caffeine citrate (20 mg/kg) was injected intraperitoneally before hypoxia ischemia (HI) and immediately, 24 hours, 48 hours and 72 hours after HI. The other two groups were injected intraperitoneally with an equal volume of normal saline at the corresponding time points. On postnatal day 12, the expression of MBP in the left subcortical white matter was detected by immunohistochemistry, and the levels of adenosine A1 receptor mRNA and A2a receptor mRNA in the left brain were detected by real-time PCR.

RESULTSThe expression of MBP in the left subcortical white matter in the HIBD group was lower than in the sham operation group (P<0.05). The MBP expression in the HIBD+caffeine citrate group was significantly higher than in the HIBD group, but was still lower than the sham operation group (P<0.05). Real-time PCR showed that the adenosine A1 receptor mRNA expression was significantly higher in the HIBD group than in the sham operation group, and it was significantly lower in the HIBD+caffeine citrate group than in the HIBD group (P<0.05).

CONCLUSIONSCaffeine citrate can improve brain white matter damage following HIBD in neonatal rats and the protection mechanism might be related with the down-regulation of adenosine A1 receptor expression.

Animals ; Animals, Newborn ; Caffeine ; pharmacology ; Citrates ; pharmacology ; Female ; Hypoxia-Ischemia, Brain ; drug therapy ; metabolism ; pathology ; Male ; Myelin Basic Protein ; analysis ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptor, Adenosine A1 ; genetics ; Receptor, Adenosine A2A ; genetics ; White Matter ; chemistry

OBJECTIVETo investigate the effects of three different ways of chronic caffeine administration on blast- induced memory dysfunction and to explore the underlying mechanisms.

METHODSAdult male C57BL/6 mice were used and randomly divided into five groups: control: without blast exposure, con-water: administrated with water continuously before and after blast-induced traumatic brain injury (bTBI), con-caffeine: administrated with caffeine continuously for 1 month before and after bTBI, pre-caffeine: chronically administrated with caffeine for 1 month before bTBI and withdrawal after bTBI, post-caffeine: chronically administrated with caffeine after bTBI. After being subjected to moderate intensity of blast injury, mice were recorded for learning and memory performance using Morris water maze (MWM) paradigms at 1, 4, and 8 weeks post-blast injury. Neurological deficit scoring, glutamate concentration, proinflammatory cytokines production, and neuropathological changes at 24 h, 1, 4, and 8 weeks post-bTBI were examined to evaluate the brain injury in early and prolonged stages. Adenosine A1 receptor expression was detected using qPCR.

RESULTSAll of the three ways of chronic caffeine exposure ameliorated blast-induced memory deficit, which is correlated with the neuroprotective effects against excitotoxicity, inflammation, astrogliosis and neuronal loss at different stages of injury. Continuous caffeine treatment played positive roles in both early and prolonged stages of bTBI; pre-bTBI and post-bTBI treatment of caffeine tended to exert neuroprotective effects at early and prolonged stages of bTBI respectively. Up-regulation of adenosine A1 receptor expression might contribute to the favorable effects of chronic caffeine consumption.

CONCLUSIONSince caffeinated beverages are widely consumed in both civilian and military personnel and are convenient to get, the results may provide a promising prophylactic strategy for blast-induced neurotrauma and the consequent cognitive impairment.

Animals ; Blast Injuries ; complications ; Brain Injuries, Traumatic ; complications ; Caffeine ; pharmacology ; Cerebral Cortex ; pathology ; Hippocampus ; pathology ; Male ; Memory Disorders ; etiology ; prevention & control ; Mice ; Mice, Inbred C57BL ; RNA, Messenger ; analysis ; Receptor, Adenosine A1 ; genetics

Paeoniflorin (PF) is the chief active component of paeonia, with diverse pharmacological actions and wide application. Recently, the effect of PF on nervous system has attracted increasingly more attention. According to current study findings, PF can ameliorate the decline of memory and learning capacities in many dementia model animals, and have effect in protecting the cerebral ischemia injury, treating Parkinson's disease, reliving pain and improving neural synapse plasticity. Thought its mechanism has not been clarified, current findings show that adenosine A1 receptor plays an important role, while M cholinergic receptor, opiate receptor, calcium ion channel and NF-KB may also play a part in paeoniflorin's effect on nervous system.
Animals ; Benzoates ; pharmacology ; Bridged-Ring Compounds ; pharmacology ; Calcium Channels ; metabolism ; Glucosides ; pharmacology ; Learning ; drug effects ; Memory ; drug effects ; Monoterpenes ; NF-kappa B ; metabolism ; Nervous System ; drug effects ; metabolism ; Receptor, Adenosine A1 ; metabolism

Cardio-renal syndromes are disorders of the heart and kidney wherein acute or long-term dysfunction in one organ may induce acute or long-term dysfunction of the other. Because of this complex organ interaction, management of cardiorenal syndrome must be tailored to the underlying pathophysiology. Clinical guidelines exist for the treatment of heart failure or renal failure as separate conditions. Thus far, however, there has been no consensus about managing patients with cardio-renal and reno-cardiac syndromes. Pharmacologic treatment remains a controversial subject. Standard cardiac drugs such as diuretics and inotropes may have limited effect because resistance often develops after long-term use. Recent studies of patients with acute cardio-renal syndromes have focused on newer therapies, including phosphodiesterase inhibitors, vasopressin antagonists, adenosine A1 receptor antagonists, and renal protective dopamine. Initial clinical trials of these agents have shown encouraging results in some patients with heart failure, but have failed to demonstrate a clear superiority over more conventional treatments. Similarly, the benefits of diuretics, aspirin, erythropoietin agents, and iron supplements for management of chronic cardiorenal syndromes are unknown.
Adenosine A1 Receptor Antagonists ; Aspirin ; Cardio-Renal Syndrome ; Consensus ; Diuretics ; Dopamine ; Erythropoietin ; Heart ; Heart Failure ; Humans ; Iron ; Kidney ; Phosphodiesterase Inhibitors ; Renal Insufficiency ; Vasopressins

OBJECTIVETo investigate the effects of injecting adenosine A1 receptor agonist (CCPA) into Baihui (GV20) on the cerebral cortex induced by the ischemia/reperfusion of middle cerebral artery occlusion (MCAO) in rats.

METHODSTwenty-four SD rats were randomly divided into four groups, i. e., the sham-operation group, the model group, the DMSO group, and the CCPA group. The MCAO model was established by thread embolism method. At the moment of ischemia/reperfusion, the rats in DMSO group and the CCPA group were injected with DMSO (20 microL) and CCPA (0.1 mmol) 20 microL into Baihui respectively. The rats' behavior, the histomorphology of ischemic penumbra in the cerebral cortex, the expressions of Bcl-2 protein, and the apoptosis rate of neurocytes were assessed.

RESULTSCompared with the model group and the DMSO group, the rats' behavior were markedly improved in the CCPA group (P<0.05). No obvious karyopyknosis and cytoplasm empty dye of neurons appeared. The Bcl-2 expressions in rats' cerebral cortex obviously increased (P<0.01). The apoptosis number of neurons obviously decreased (P<0.01).

CONCLUSIONSInjecting CCPA into Bahui improved the rats' behavior and histomorphology in the ischemic penumbra, elevated the expressions of Bcl-2 protein, and reduced the neurons apoptosis rate in the ischemic penumbra. It alleviated the cerebral ischemia-reperfusion injury. Therefore, it could be taken as a new treatment method.

Acupuncture Points ; Adenosine A1 Receptor Agonists ; administration & dosage ; pharmacology ; therapeutic use ; Animals ; Brain Ischemia ; metabolism ; therapy ; Cerebral Cortex ; drug effects ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; metabolism ; therapy