Ethanol Induces Sedation and Hypnosis via Inhibiting Histamine Release in Mice.

Ethanol is one of the most highly abused psychoactive compounds worldwide and induces sedation and hypnosis. The histaminergic system is involved in the regulation of sleep/wake function and is a crucial player in promoting wakefulness. To explore the role and mechanism of the histaminergic system in ethanol-induced sedation and hypnosis, we recorded locomotor activity (LMA) and electroencephalography (EEG)/electromyography (EMG) in mice using an infrared ray passive sensor recording system and an EEG/EMG recording system, respectively, after administration of ethanol. In vivo microdialysis coupled with high performance liquid chromatography and fluorometry technology were used to detect histamine release in the mouse frontal cortex (FrCx). The results revealed that ethanol significantly suppressed LMA of histamine receptor 1 (H1R)-knockout (KO) and wild-type (WT) mice in the range of 1.5-2.5 g/kg, but suppression was remarkably stronger in WT mice than in H1R-KO mice. At 2.0 and 2.5 g/kg, ethanol remarkably increased non-rapid eye movement sleep and decreased wakefulness, respectively. Neurochemistry experimental data indicated that ethanol inhibited histamine release in the FrCx in a dose-dependent manner. These findings suggest that ethanol induces sedation and hypnosis via inhibiting histamine release in mice.

A positive association between the human tissue kallikerin gene A2233C polymorphism and blood pressure response to benazepril.

BACKGROUND: It is generally believed that essential hypertension is influenced by both genetic and environmental factors, as well as their interactions. Tissue kallikrein encoded by the tissue kallikrein gene (KLK1) is a key serine proteinase of kallikrein-kinin system, which is capable of generating potent vasactive peptides, kinins, by selective cleavage of the kininogen substrate. It was reported that the A2233 → C polymorphism in KLK1 gene is associated with essential hypertension. The aim of this study was to examine whether the molecular variations of KLK1 play role in determining the therapeutic response to benazepril, an ACE inhibitor. METHODS: A total of 331 hypertensive individuals were recruited and treated with benazepril for 15 days. A variant impact of KLK1 A2233C was revealed. Chi-square analysis showed that the hypertensive subjects with the mutation genotype (AC + CC) had a higher proportion in systolic blood pressure (SBP, 88.1% vs. 79.0%, χ2 = 4.141, p = 0.042) and diastolic blood pressure (DBP, 91.1% vs. 79.2%, χ2 = 9.336, p = 0.002), respectively, to benazepril medication in good responders than in poor responders. Logistic regression analysis indicated that the hypertensive subjects with AC + CC genotype were more sensitive to the benazepril therapy in SBP (OR=1.97, 95% CI: 1.02-3.80, p = 0.044) and DBP (OR = 1.91, 95% CI: 2.69-5.16, p = 0.003), as compared with those hypertensive subjects with AA genotype. CONCLUSION: Our findings suggest that the A2233C polymorphism of KLK1 may be a marker of evaluation of hypertensive subjects' responses to angiotensin I converting enzyme inhibitors benazepril.

[Pharmacokinetics of tramadol hydrochloride in the extracellular fluid of mouse frontal cortex studied by in vivo microdialysis].

The paper aims to explore the studying method for the pharmacokinetics of drugs in target organs, the pharmacokinetic process of tramadol hydrochloride in the extracellular fluid of frontal cortex (FrCx) of mice was investigated. Six male mice (Kunming strain) were anaesthetized (urethane, 1.8 g x kg(-1), ip) and secured on a stereotaxic frame. A microdialysis probe was implanted into the FrCx and perfused with artificial cerebrospinal fluid at a flow rate of 2 microL x min(-1). One hour later, mice were administrated (ip) with tramadol hydrochloride (50 mg x kg(-1)) and dialysates were collected continuously at 12-min intervals (24 microL each) for 6 h. The tramadol concentration in dialysates was determined by HPLC-Ultraviolet detection method, and the concentration-time curve and pharmacokinetic parameters of tramadol were calculated with DAS software. The results showed that the pharmacokinetic process of tramadol in the FrCx extracellular fluid of mice was fitted to a two-compartment open model, and the main pharmacokinetic parameters t1/2alpha, t1/2beta, t(max), C(max) and AUC(0-infinity) were (0.27 +/- 0.05) h, (2.72 +/- 0.24) h, (0.50 +/- 0.10) h, (2 110.37 +/- 291.22) microg x L(-1) and (4 474.51 +/- 441.79) microg x L(-1) x h, respectively. In conclusion, a studying method for pharmacokinetics of drugs in the target organ is established, which is simple and feasible. Tramadol hydrochloride shows a two-compartment model in the extracellular fluid of the mouse FrCx, and the distribution- and elimination half-life are 0.5 h and 2.7 h, respectively.

[Pharmacokinetics--pharmacodynamics of modafinil in mice].

To guide the reasonable clinical application of modafinil (MOD), pharmacokinetics and pharmacodynamics of MOD in mice and the correlation between them were investigated. Male mice (Kunming strain) were given a single oral dose of MOD (120 mg x kg(-1)). The plasma concentration of MOD was measured by HPLC and the pharmacokinetic parameters were calculated with DAS 3.0 software. For another batch of male Kunming strain mice, their locomotor activities were recorded by an infrared ray passive sensor after a same oral dose of MOD, and the synchronization and correlation between the changes of MOD plasma concentration and the locomotor activity induced by MOD were compared and analyzed. The results showed that the plasma concentration-time curve of MOD was fitted to two-compartment open model with a first order absorption. The main pharmacokinetic parameters t1/2alpha, t1/2beta, t(max), C(max) and AUC(0-inifinity) were 0.42 h, 3.10 h, 1.00 h, 41.34 mg x L(-1) and 142.22 mg x L(-1) x h, respectively. MOD significantly increased locomotor activity and the effect lasted for about 4 h. The changes of MOD plasma concentration and the locomotor activity induced by MOD were synchronous. In conclusion, there is a significant correlation between the effect of MOD and its plasma concentration after administration of 120 mg x kg(-1) in mice.

Valsartan-mediated chronotherapy in spontaneously hypertensive rats via targeting clock gene expression in vascular smooth muscle cells.

OBJECTIVE: This study was to investigate the underlying mechanisms of valsartan chronotherapy in regulating blood pressure variability. METHODS: RT-PCR was used to assay clock genes expression rhythm in the hypothalamus, aortic vessels, and target organs after valsartan chronotherapy. WB was used to measure Period 1 (Per1), Period 2 (Per2) protein expression in aortic vessels, as well as to measure phosphorylation of 20-kDa regulatory myosin light chain (MLC20) in VSMCs. RESULTS: Specific clock genes in the hypothalamus, and Per1 and Per2 in aorta abdominalis, exhibited disordered circadian expression in vivo. Valsartan asleep time administration (VSA) restored circadian clock gene expression in a tissue- and gene-specific manner. In vitro, VSA was more efficient in blocking angiotensin II relative to VWA, which led to differential circadian rhythms of Per1 and Per2, ultimately corrected MLC20 phosphorylation. CONCLUSION: VSA may be efficacious in regulating circadian clock genes rhythm, then concomitantly correct circadian blood pressure rhythms.

[Tissue distribution in mice of danshensu from sodium danshensu and Salvia miltiorrhiza injection].

OBJECTIVE: To determine the concentration in mice of danshensu from sodium danshensu and Salvia miltiorrhiza injection and undertake comparative study of them as well as to assess the effect of other components of S. miltiorrhiza injection on the tissue distribution of danshensu. METHOD: Mice received intraperitoneal administration of sodium danshensu or S. miltiorrhiza injection (equal to danshensu 60 mg x kg(-1)) respectively, and was executed 30 minutes after administration. The concentration of danshensu in different tissues was separately determined by high performance liquid chromatographic method. RESULT: The characteristic profiles of sodium danshensu in different tissues were C(kidney) > C(spleen) > C(lung) > C(heart) > C(liver). The characteristic profiles of danshensu from S. miltiorrhiza injection in different tissues were C(kidney) > C(lung) > C(spleen) > C(heart) approximately C(liver). The concentration of danshensu in S. miltiorrhiza injection in liver and kindey was higher than sodium danshensu itself. CONCLUSION: It was suggested that the other components in S. miltiorrhiza injection influent the distribution profile in tissues of danshensu.

[Comparative pharmacokinetic study of sodium Danshensu and Salvia miltiorrhiza injection in rat].

OBJECTIVE: To develop a HPLC method for determination of the concentration of Danshensu in rat plasma and undertake comparative pharmacokinetic study of sodium danshensu and Salvia miltiorrhiza injection in rat as well as to assess the effect of other components of Salvia miltiorrhiza injection on the pharmacokinetics of Danshensu. METHOD: Rats received an iv. infusion of sodium Danshensu or S. miltiorrhiza injection (equal to Danshensu 30 mg x kg(-1)). Blood samples were collected from carotid artery. Plasma concentration of Danshensu extracted with perchloric acid was measured. The pharmacokinetic parameters were calculated with DAS2.0 software. RESULT: A good linear relationship of Danshensu was obtained from the range of 0.5 to 80.0 mg x L(-1), and the lowest limit of determination was 0.2 mg x L(-1). The plasma concentration time curves of Danshensu were best fitted with two-compartment models for Danshensu itself and for Salvia miltiorrhiza injection as well. The pharmacokinetic parameters such as t1/2alpha, AUC, CL had significant differences. CONCLUSION: The concomitant components in Salvia miltiorrhiza injection influence the pharmacokinetic properties of Danshensu and speed up its disposition and elimination.

Combined effects of cigarette smoking, alcohol drinking and eNOS Glu298Asp polymorphism on blood pressure in Chinese male hypertensive subjects.

INTRODUCTION: Genetic factors and lifestyle exposures, as well as their combinations, play important roles in the development of hypertension. We examined whether cigarette smoking, alcohol drinking and the Glu298Asp polymorphism of the endothelial nitric oxide synthase (eNOS) gene generate combined effects on blood pressure (BP) in hypertensive subjects. METHODS: A total of 342 essential hypertensive subjects were recruited from Susong community in Anhui province, China, from July 2017 to January 2018, and the plasma biochemical parameters and the genotype on Glu298Asp polymorphism were determined. RESULTS: There were no gender differences in the distributions of alleles and genotypes in hypertensive subjects. The proportions of cigarette smoking and alcohol drinking in male hypertensive subjects were remarkably higher than those in the females (p<0.001). The systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels of mutant genotypes (Glu/Asp and Asp/Asp) were significantly higher than those of wild genotype (Glu/Glu) (p=0.013 and 0.026, respectively) in male hypertensive subjects. Moreover, the SBP and DBP levels of the mutant genotype were remarkably higher than those of wild genotype in both cigarette smoking and alcohol drinking male hypertensive subjects (p=0.034 and 0.043, respectively). CONCLUSIONS: Cigarette smoking, alcohol drinking and the Glu298Asp polymorphism of the eNOS gene generate combined effects that increase the susceptibility of the mutant genotype to BP in Chinese male hypertensive subjects.

Valsartan chronotherapy reverts the non-dipper pattern and improves blood pressure control through mediation of circadian rhythms of the renin-angiotensin system in spontaneous hypertension rats.

Background: Numerous clinical studies have evaluated valsartan and found more efficacious control of blood pressure (BP) variability when administered before sleep. The treatment leads to improved outcomes when compared to administration upon awakening. The mechanism underlying this etiology is not fully understood. The present study investigates the safety and efficacy of asleep administration of valsartan in spontaneously hypertensive rats (SHR) with a non-dipping blood pressure pattern compared to SHRs receiving administration during awake time. Materials and Methods: 84 Male SHRs and 28 male Wistar-Kyoto rats (WKY) were kept under a strict alternating 12-h light/dark cycle. WKYs were utilized as a non-disease control. Meanwhile, SHRs were randomly divided into three groups: untreated, Valsartan asleep administration (VSA) and Valsartan awake administration (VWA) respectively. The VSA group was treated with valsartan (30 mg/kg/d) after the light onset, while the VWA group was treated with valsartan (30 mg/kg/d) after light offset. Both groups were treated for 6 weeks. Tail artery blood pressure was measured every 4 h via a noninvasive tail cuff blood pressure measurement method. HE and Masson staining were used to evaluate any damage within the target organs. ELISA was used to determine the 24-h plasma renin-angiotensin system (RAS) concentration at 4-h intervals. Results: Based on our findings, VSA significantly reduced 24-h and evening mean BP and restored the abnormal circadian rhythm compared to VWA, which attenuated injuries in the majority of target organs except for the kidneys. Furthermore, VSA was found to activate RAS during the light cycle and inhibit it during the dark cycle. Conversely, VWA was found to deactivate RAS throughout the day which may be related to the circadian BP rhythm. Conclusion: VSA may be more efficacious than VWA in controlling BP, circadian BP rhythm and blood RAS rhythm. Recent cardiovascular outcome investigations substantiate that chronotherapy treatment might be a novel therapeutic strategy for hypertension therapy. Abbreviations: Angiotensin-converting enzyme (ACE); Angiotensin converting enzyme inhibitors (ACEIs); Angiotensin II (ANG II); Analysis of variance (ANOVA); Angiotensin receptor blockers (ARBs); Blood Pressure (BP); Calcium Antagonists Calcium Channel Blockers (CCB); Chronic kidney diseases (CKD); Sodium carboxyl methyl cellulose (CMC-Na); Cardiac mass index (CMI); Cardiovascular diseases (CVD); Diastolic blood pressure (DBP); Enzyme-linked immunosorbent assay (ELISA); Hematoxylin-eosin (H&E); Kidney mass index (KMI); Liver mass index (LMI); Mean arterial blood pressure (MAP); Plasma renin concentration (PRC); Renin-angiotensin system (RAS); Rennin (REN); Systolic blood pressure (SBP); Student-Newman-Keuls q test (SNK-q test); Spontaneous hypertension rats (SHR); Valsartan asleep Administration (VSA); Valsartan awake Administration (VWA); Wistar-Kyoto (WKY); Mesor (M); Amplitude (A); Phase (φ).

Hepatotoxicity and toxicokinetics of ketoconazole in rabbits.

AIM: To study the relationship between hepatotoxicity and toxicokinetics of ketoconazole in rabbits. METHODS: Normal rabbits were given intragastric gavage ketoconazole 40, 80, and 160 mg/kg. Ketoconazole plasma concentrations were measured by high performance liquid chromatography. Toxicokinetic parameters were determined from the plasma concentration-time data with the 3P97 software package. Activities of serum glutamate-pyruvate-transaminase and glutamate-oxalate-transaminase and hepatic histopathological changes were observed at 36 h after administration. The relationship between hepatotoxicity and toxicokinetic parameters of ketoconazole was analyzed by linear correlation. RESULTS: The concentration-time curves of three doses of ketoconazole fitted well into a two-compartment model. The proportional increase in the area under the plasma concentration-time curve (AUC) was more than that in the dose after the dose reached 80 mg/kg. Ketoconazole resulted in a marked elevation in the enzyme activities and significant damage of hepatocytes. Hepatotoxicity induced by ketoconazole was correlated to the dose, clearance (CL), maximum plasma concentration (Cmax), and most closely correlated to AUC when it was assessed by elevation transaminases in serum. CONCLUSION: The severity of ketoconazole-induced hepatotoxicity was closely related to the exposure level (AUC) of the drug.