ABSTRACT
Our previous studies have confirmed that the crude tentacle-only extract (cTOE) from the jellyfish Cyanea capillata (Cyaneidae) exhibits hemolytic and cardiovascular toxicities simultaneously. So, it is quite difficult to discern the underlying active component responsible for heart injury caused by cTOE. The inactivation of the hemolytic toxicity from cTOE accompanied with a removal of plenty of precipitates would facilitate the separation of cardiovascular component and the investigation of its cardiovascular injury mechanism. In our research, after the treatment of one-step alkaline denaturation followed by twice dialysis, the protein concentration of the treated tentacle-only extract (tTOE) was about 1/3 of cTOE, and SDS-PAGE showed smaller numbers and lower density of protein bands in tTOE. The hemolytic toxicity of tTOE was completely lost while its cardiovascular toxicity was well retained. The observations of cardiac function, histopathology and ultrastructural pathology all support tTOE with significant cardiovascular toxicity. Blood gas indexes and electrolytes changed far less by tTOE than those by cTOE, though still with significant difference from normal. In summary, the cardiovascular toxicity of cTOE can exist independently of the hemolytic toxicity and tTOE can be employed as a better venom sample for further purification and mechanism research on the jellyfish cardiovascular toxic proteins.
Subject(s)
Cardiovascular System/drug effects , Cnidarian Venoms/toxicity , Scyphozoa/metabolism , Animals , Blood Gas Analysis , Heart Ventricles/drug effects , Hemolysis , Male , Microscopy, Electron, Transmission/methods , Myocardium/metabolism , Myocytes, Cardiac/drug effects , Rats , Rats, Sprague-DawleyABSTRACT
Previous studies in our laboratory have shown that the cardiotoxicity is the main reason for rat death caused by tentacle-only extract from jellyfish Cyanea capillata. However, the direct cardiotoxicity in vitro and its mechanisms of toxic action remain unclear. The current studies were performed by using the Langendorff-perfused isolated heart model, which showed a dose-dependent hemodynamic and electrocardiogram changes. Heart injury-related enzymes increased. Histopathological analysis showed early ischemic damage in the myocardium. The Ca channel blockers nifedipine and verapamil led to a marked improvement in recovery of cardiac function, including heart rate, left ventricular developed pressure, positive and negative first derivatives of intraventricular pressure, coronary flow, left ventricular end-diastolic pressure, and electrocardiogram changes. Tentacle-only extract-induced cardiac dysfunction could be partly improved by the pretreatments of both propranolol and phentolamine, but not by either atropine or neostigmine at all. In conclusion, we have verified the direct cardiotoxicity of tentacle-only extract from jellyfish C. capillata by the Langendorff isolated heart model, which consisted of 3 separate parts: sinoatrial node malfunction, cardiomyocyte injury, and coronary spasm. The potential mechanism might be attributed to the overactivation of L-type Ca channel, ß- and α-adrenergic receptors, but not cholinergic receptors.
Subject(s)
Cnidarian Venoms/toxicity , Myocardial Ischemia/chemically induced , Myocytes, Cardiac/drug effects , Sinoatrial Node/drug effects , Animals , Calcium Channels, L-Type/drug effects , Calcium Channels, L-Type/metabolism , Coronary Vasospasm/chemically induced , Dose-Response Relationship, Drug , Electrocardiography , Heart Rate/drug effects , Hemodynamics , Male , Myocytes, Cardiac/pathology , Nifedipine/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, Adrenergic, alpha/drug effects , Receptors, Adrenergic, alpha/metabolism , Receptors, Adrenergic, beta/drug effects , Receptors, Adrenergic, beta/metabolism , Sinoatrial Node/pathology , Verapamil/pharmacologyABSTRACT
Objective:To evaluate the biological characters of C57-TgN(HBV adr2.0)SMMU transgenic mice. Methods: Integration,expression,replication and histology change of hepatitis B virus gene in F6 transgenic mice were estimated by ge-nomic DNA PCR,Western blotting,ELISA,immunohistochemistry,serum DNA PCR,transmission electron microscopy and H-E staining. Results: Hepatitis B virus gene was integrated into F6 C57-TgN(HBV adr2. 0)SMMU transgenic mice and expressed HBsAg,HBcAg and X protein in liver tissue. HBsAg and HBeAg were expressed in serum of 19. 54% and 3. 39% F6 transgenic mice. Hepatitis B virus were replicated in serum and liver tissue of transgenic mice. Long-term integration,expression and replication of hepatitis B virus gene induced pathological lesion of transgenic mice liver and lung. Conclusion: C57-TgNCHBV adr2. 0)SMMU transgenic mice line has the biological characters including integration of hepatitis B virus gene into genomic DNA,expression and replication of hepatitis B virus gene in serum and liver, and histological change in liver and lung. It is a valuable animal system to study pathogenesis, treatment and prevention of hepatitis B virus.
ABSTRACT
AIM and METHODS: Electron cytochemical methods were used to study the changes of calcium and reactive oxygen species in rat kidney during ischemia and reperfusion period.RESULTS:By the end of 1h ischemia, intra-cellular calcium increased. There were no H 2O 2 generation at this time. In the early reperfusion period, large amount of H 2O 2 generated. At this time, there were no evident changes of intra-cellular calcium compare with 1h ischemia group. In the later reperfusion period, less H 2O 2 generated. Intra-cellular calcium increased continuously.CONCLUSION:Calcium and reactive oxygen species all participated in ischemia-reperfusion injury, but the time they participated and their effects were different.
ABSTRACT
Objective: To compare nephrotoxicity and ototoxicity of gentamycin administered in single dose or multiple dose daily in guinea pigs. Methods: Thirty two male guinea pigs were divided into physiological saline control, single dose group daily (gentamycin, 120 mg/kg, 1/d) and multiple dose group daily (gentamycin, 60 mg/kg, 2/d). The physiopathology of renal and cochlea in guinea pigs were examined using auditory brainstem response (ABR), SC sound irritation and electron microscope. The gentamycin concentrations in serum and in perilymph were monitored by fluorescene polarization immunoassay (FPIA). Results: (1) Compared with control group, both gentamycin single and mulitiple daily doses injuried kidney and cochlea to some extent.The injury of multiple dose groups were worse than that the single dose groups ( P
ABSTRACT
In the process of hepatocarcinogenesis induced by diethylnitrosamine (DENA) in rats, the hepatocellular ultrastructure and G-6-Pase reactions in hepatic nodes were observed by electron microscope. The results are as follows: As compared with normal hepatocytes, cell junctions were fewer, even disappeared in some areas and intercellular spaces were wider; in some cells, nuclear membranes invaginated into the nucleoplasms frequently, micleoli were enlarged, mitochondria appeared swollen and their cristae were scanty- and short, and depolymerized ribosomes dropped off the dilated rough endoplasmic reticulums; in some seriously diseased cells, nucleoli were enlarged, abundant free ribosomes were present, but the' other organelles were in lower differencial state. G-6-Pase reactions were positive before the 8th week of DENA induction and negative after the 12th week. These suggest the hepatocellular metabolic disturbance and low differenciation.
ABSTRACT
Objective:To study the instant and short term effects of diagnostic ultrasound on ultrastructure and hydrogen peroxide cytochemistry of human villi. Methods: Fifteen healthy women with gestational ages of 6 to 8 weeks were divided into 4 groups. Group A( n =3),B( n =4),C( n =4) and D( n =4) were exposured to diagnostic ultrasound for 0,10,20 and 20 min respectively. In group A, B, and C, the villi were taken out immediately after ultrasound exposure and were studied. In group D, the villi were taken out 3 d after ultrasound exposure. Results: The results showed that there were changes only in group C. Enlargement of endoplasmic reticulum and mitochondrial intracristal space were observed in syntrophoblast cells. In group A, B, and D, there were no evident abnormality. Conclusion: The conventional acoustic exposure of diagnostic ultrasound is safe for human villi.
