Research on Acute Toxicity of Penthorum chinense Pursh. Total Flavonoids and Therapeutic Effect on AFL Rats

[Objectives]To study the acute toxicity of total flavonoids in Penthorum chinense Pursh. and the therapeutic effect on AFL( Alcoholic Fatty Liver). [Methods] The liquid of total flavonoids in P. chinense Pursh. was intragastrically administered to the test group rats in the maximum concentration and the maximum administration volume,an equal volume of solvent was given to the control group,and it was observed continuously for 14 d; 1. 5% ferrous sulfate feed was used for feeding,the alcohol intragastric administration method was used to copy the AFL rats model,and the therapeutic effect of total flavonoids in P. chinense Pursh. on the fatty liver rats was observed. [Results]No rat died in the medication administration group and the control group,there was no acute toxicity reaction,and the maximum tolerance dose of total flavonoids in P. chinense Pursh. for the rats by intragastric administration was 33. 6 g/kg; rats suffered AFL 6 weeks after the alcohol intragastric administration. For the 800 mg/kg P. chinense Pursh. total flavonoids and 2 000 mg/kg P. chinense Pursh. extract with the same dose as that of the P. chinense Pursh. crude drug,P. chinense Pursh. total flavonoids played a more significant role than P. chinense Pursh. extract in lowering oil red O staining area in AFL rats' liver tissue and reducing the ALT,AST,TC,TG content in AFL rats' serum. [Conclusions]The P. chinense Pursh. total flavonoids had low acute toxicity,and had a greater therapeutic effect on the AFL rats than the P. chinense Pursh.extract.

Circuit-Specific Control of Blood Pressure by PNMT‑Expressing Nucleus Tractus Solitarii Neurons

The nucleus tractus solitarii(NTS)is one of the morphologically and functionally defined centers that engage in the autonomic regulation of cardiovascular activity.Phenotypically-characterized NTS neurons have been implicated in the differential regulation of blood pressure(BP).Here,we investigated whether phenylethanolamine N-methyltransferase(PNMT)-expressing NTS(NTS^(PNMT))neurons contribute to the control of BP.We demonstrate that photostimulation of NTS^(PNMT)neurons has variable effects on BP.A depressor response was produced during optogenetic stimulation of NTS^(PNMT)neurons projecting to the paraventricular nucleus of the hypothalamus,lateral parabrachial nucleus,and caudal ventrolateral medulla.Conversely,photostimulation of NTS^(PNMT)neurons projecting to the rostral ventrolateral medulla produced a robust pressor response and bradycardia.In addition,genetic ablation of both NTS^(PNMT)neurons and those projecting to the rostral ventrolateral medulla impaired the arterial baroreflex.Overall,we revealed the neuronal phenotype-and circuit-specific mechanisms underlying the contribution of NTS^(PNMT)neurons to the regulation of BP.