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Glaucoma and retinal degenerations are two important ocular diseases that often cause massive impacts to vision in both humans and animals. Rat models are commonly used to explore the complex pathophysiology and potential treatments of these diseases. The models of high intraocular pressure (HIOP)-induced retinal ischemia-reperfusion imply the ischemic outcome weight on the inner retina layers (including the nerve fiber layer, retinal ganglion cell (RGC) layer, inner plexiform layer (IPL), and inner retinal layer (INL)) that eventually progressed to the outer retinal layers. Depending on the duration (cycles) of ischemic treatment, more glaucoma pathological change signs may be exhibited more obviously with time. The model requires a short ischemic treatment and anticipates an adequately long period of disease manifestation. To investigate photoreceptor-led retinal degeneration, rat models for light-induced retinopathy are commonly used and it is predominantly attributed to the photoreceptor cells damage of ONL and OPL loss by high intensity of light exposure. This model unraveled the pathophysiological impairment of phototransduction as well as disease mechanisms involving oxidative stress and inflammatory process of the outer retinal layer. With the knowledge gained from the research using these animal models, better understanding of the disease mechanisms in terms of its pathophysiology and molecular changes can be achieved. Besides, the rat models can serve as the key basis for further investigation into the therapeutic or preventive perspectives of these retinopathies.

Cortical spreading depression (CSD) is a pathophysiological phenomenon. There are sufficient evidences to prove that CSD plays an important role in some neurological disorders. However, exact mechanisms of its initiation and propagation are still unclear. Previous studies showed that glutamate receptors could be concerned with CSD, but those studies were mostly performed oriented to ionotropic glutamate receptors (iGluRs). There is relatively little report about effects of metabotropic glutamate receptors (mGluRs) on CSD. Here, we applied optical intrinsic signal imaging (OISI) combined with direct current (DC) potential recording to examine influences of some mGluRs antagonist (or agonist) on CSD propagation in rat's brain, to indirectly validate actions of some mGluRs on CSD. We found that N-acetyl-L-aspartyl-L-glutamate (NAAG, an agonist at mGluR3) inhibited the propagation of CSD, and the inhibition was gradually developed with time. However, 6-methyl-2-phenylethynyl-pyridine (MPEP, an antagonist of mGluR5) did not produce any significant alterations with the CSD propagation. Our findings suggest that mGluR3 could play an important role in the CSD propagation, but the activity of mGluR5 was comparatively weak. These findings can help to understand the propagation mechanism of CSD, and consider the therapy of some neurological diseases involved with CSD.

The influence of ischemia–reperfusion (I/R) action on pancreatic blood flow (PBF) and the development of acute pancreatitis (AP) in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging (LSCI). Additionally, the optical properties in norm and under condition of AP in rats were assessed using a modified integrating sphere spectrometer and inverse Monte Carlo (IMC) software. The results of the experimental study of microcirculation of the pancreas in 82 rats in the ischemic model are presented. The data obtained confirm the fact that local ischemia and changes in the blood flow velocity of the main vessels cause and provoke acute pancreatitis.

Background: The stent technique of microvascular anastomosis, in which a stent is placed in the vessel before creating the anastomosis, is useful for accurate anastomosis formation, but the manipulation involved in stent insertion into the vessel and withdrawal from the anastomosis still poses problems. In this study, a silastic stent containing a copper wire-bent in an L-shape was designed and its utility in microvascular anastomosis was investigated in rats.

Methods: Eighty end-to-end anastomosis procedures of the right femoral artery and vein were performed in rats. Anastomoses were conducted either by the conventional method (Method C) or using L-shaped silastic stents (Method L), with anastomosis condition assessed after one side had been sutured, at the completion of vascular anastomosis and on postoperative day 7.

Results: After one side had been sutured, suture errors were observed in three veins with Method C. At the completion of vascular anastomosis, impaired blood flow was observed in two arteries and two veins with Method C, and in one artery with Method L. On postoperative day 7, impaired blood flow was observed in one artery and one vein with Method C and in one vein with Method L.

Conclusions: The use of L-shaped silastic stents preserved the advantages of the stent technique while simplifying stent manipulation. This technique may help reduce the risk of intimal trauma.