Study of electrophysiological mechanism of dopamine inhibiting insulin secretion by Kv channels / 中国药理学通报

Aim To study the electrophysiological mechanism of dopamine inhibiting insulin secretion hv voltage-dependent potassium ( Kv) channels.Methods Islets and (3 cells were isolated from male SD rats.D,-like receptor agonist ( SKP38393), D2-like receptor agonist (Quinpirole) and antagonist (Epiclopride) were used according to the experiment.Insulin secretion was detected by insulin radioimmunoassay.Whole-cell j J patch-clamp technique was applied to detect Kv channel currents and action potential duration of p cells.Di- BAC4(3) staining was used to observe membrane potential.Results SKF38393 did not affect insulin secretion and the Kv channel currents.Quinpirole signifi cantly inhibited insulin secretion and increased Kv channel currents.Dopamine significantly inhibited insulin secretion, increased Kv channel currents and shortened action potential duration of p cells, which could be reversed by epiclopride.In addition, dopamine de-creased membrane potential of INS-1 cells.Conclusions Dopamine inhibits insulin secretion by acting on D2-like receptors, resulting in actived Kv channels, shortened action potential duration and decreased cell membrane potential.

The insulinotropic effects and its relevant mechanism of telmisartan in rats / 中国药理学通报

Aim To investigate the insulinotropic effect of telmisartan anrl the underlying electrophysiological mechanism.Methods Islets and cells were isolated from Wistar rats.Islets were incubated with drugs un¬der different conditions, then supernatant liquid was collected for insulin secretion.Intracellular Ca" + ( Ca'+ j) levels of (3-cells were measured by calcium imaging technology.Patch-clamp technology was ap¬plied to detect effects on voltage-gated potassium chan¬nel ( Kv ) , and voltage-gated calcium channel ( VGCC ).Results Not affecting insulin secretion un¬der low glucose condition, telmisartan dose-dependent- ly stimulated insulin secretion under high glucose con¬ dition, and stimulation was enhanced with increasing glucose concentration.Acute increases of Ca' + concentration were elicited by telmisartan under high glucose condition.Telmisartan decreased current den¬sity of Kv channel, and increased VGCC current densi¬ty.Conclusions Telmisartan enhanced Ca~+ ; lev¬els of p-cells through its action on Kv channel and VGCC, thereby amplifying glucose-stimulated insulin secretion.

Relationship between the increase of fibrous and fatty in atrioventricular node and narrowing of the atrioventricular node artery / 法医学杂志

OBJECTIVE@#To explore relationship between increase of fibrous and fatty in atrioventricular node (AVN) and narrowing of the AVN artery. To analyze the cause of pathological fibrosis and fatty infiltration in AVN.@*METHODS@#One hundred and nineteen cases of sudden cardiac death determined by autopsy were selected and the histological sections were examined with Image-pro plus software to calculate the AVN area, AVN artery inside-diameter, AVN artery lumen area(LA) , AVN artery perimeter area(PA), fibrous area and fatty area. All cases were divided into two groups: narrowing of artery group and normal control group. The changes of the PA/LA value and the fibrous and fatty contents were evaluated.@*RESULTS@#The PA/LA value is the highest in 21-40 age group. The difference of the fatty contents and total interstitial tissue was statistical significance in the two groups under 40 years of age.@*CONCLUSION@#There is some relationship between the narrowing of the AVN artery and the increase of interstitial contents in AVN.

Traffic accidents associated with emotional stress after divorce / 法医学杂志

In recent years, the traffic accidents increased gradually, especially those caused by the drivers daily emotional abnormality and in which the drivers were liable. This article reviewed the traffic accidents caused by divorced driver's emotional abnormality, illustrated the features of those accidents from the gender, age, occupation and mileage of drivers. It was considered that the major cause of those accidents was excessive drinking due to drivers' emotional stress. Suggestions about preventing the traffic accidents caused by emotional abnormality were put forward so as to make the corresponding rules and finally decrease the emotional abnormality traffic accidents.

The prospect of application of toxicogenetics/pharmcogenetics theory and methods in forensic practice / 法医学杂志

Individual response to drugs, toxicants, environmental chemicals and allergens varies with genotype. Some respond well to these substances without significant consequences, while others may respond strongly with severe consequences and even death. Toxicogenetics and toxicogenomics as well as pharmacogenetics explain the genetic basis for the variations of individual response to toxicants by sequencing the human genome and large-scale identification of genome polymorphism. The new disciplines will provide a new route for forensic specialists to determine the cause of death.

Retinal examination with ophthalmic endoscopy in forensic autopsy / 法医学杂志

Autopsy by forensic pathologist is a main mean currently to determine the cause of sudden unexpected death. Retinal examination is important but seldom performed during a forensic autopsy for various reasons. The value of retina examination has not been recognized. With invention of ophthalmic endoscopy and its subsequent application in postmortem retina examination, it has proved to be useful adjunct to determine the cause of death and to estimate the postmortem interval.

The application of radiological imaging in the forensic pathology about cervical part / 法医学杂志

Multislice spiral computed tomography (MSCT) and magnetic resonance imaging (MRI) are useful to analyze cervical injury. Especially in injury of skeleton and soft tissue, it has equal value with conventional autopsy. Even they can reparation some shortcoming consisted in the cervical part autopsy. In some difficult postmortem examination of decomposed, charred or highly infectious cadavers and in some religion country, they should be a useful alternative way to examine injury in cervical part of cadaver such as mechanical asphyxia, whiplash injury, vertebra injury, or vascular injury.