The Primary Research Of Effects On The Rat's Visual System By Anesthetisia

Visual electrophysiology can reflect the function of different levels of the visual system, which measures the variety of bioelectricity during vision, and is marvelous because of its non-injury, exactness and well repeatition. It is electrophysiology that plays an important role in the diagnoses, identification from differential diagnoses, evaluation of the prognosis of diseases and objective visual function in ophthalmology[1]. The machine of the electrophysiology examination is boosted by the great development of the science and technology, and the measurement and analysis is more improvable and consummately. The electrophysiology has also been used largly in researchs, such as animal visual system effected by various factors, mechanism of the visual system and the functions of relative genes or proteins etc. Although electrophysiology has been advanced in the clinical ophthalmology, there are some limitations when it is used in the animal experiments such as low level of repeatition and reliability. That is largely owing to difficulty in the fixation of the animal's visual focus and anesthesia etc. The effective anesthesia of the animal in electrophysiology is able to reduce interference, increase the signal-to-noise ratio (SNR) and in favor of getting exact result of the animal experiments. Based on the manifestationeffects of anesthesia on the SD rats' visual electrophysiology, main objects of this research are as following: 1. The effect of different anesthetic drugs on the rat visual electrophysiology; 2. The effect of different intervals of anesthesia on the rat's visual electrophysiology; 3. The research of antagonization of ketamine to the damage of the glutamine overloading. 4. The effect of different stimulus frequencies and intensities on the rat light adaptation flicker electrophysiology.Methods and material:Sprague-Dawley albino male rats, which were no opacity observed by ophthalmoscope, were used in present study and grouped according to the different experimental settings. Anesthesia drugs: soluble pentobarbitone, ketamine hydrochloride, Sumianxin(846) , urethane. Rats were all treated with anesthesia drugs and vehicle by intraperitoneal injection (i.p.). When cornea reflection vanished (-), which was checked by cotton swab, the rats were considered getting in the anesthesia condition. The duration between cornea reflect vanish (-) and comeback (+) was deemed to the period of anesthesia condition. The relaxation of muscle was judged by counteractions of the limbs. The changes of corneas and lens after anesthesia were observed by slit lamp and the photos were catched by electric camera. The intraocular pressure (IOP) of the anesthetic animals were, tested by Tono-Pen XL(Medtronic Solan in USA)^. The rats were administrated through Intravitreous injection (IVI) . The functions of the retina, optic tract and visual cortex (area VI) were inspected by visual electrophysiology.Result:1. The effect of different anesthetic drugs on the rat's visual electrophysiology.All of the four drugs could affect the intraocular pressure differently.Sumianxin and ketamine increase IOP, while pentobarbital and urethane decreased IOP. The pictures photoed by slit lamp just after anesthesia showed that all 4 durgs could course the cornea edema, and some lens were observed opacity. Those cornea edema and lens opacity disappeared after 12 h from anesthesia. The rats which administrated by Sumianxin (846) , pentobarbital, urethane, ketamine, had been in the conditions of general anesthesia. In all of the recordings Sumianxin (846), pentobarbitone, urethane, ketamine can get satisfying waves, but in defferent drugs there were some special. Scot-ERG (scotopic electroretinograph) revealed that the latency of b-wave was most delayed in urethane group and shortest in ketamine group at the standard light intensity. The amplitude CVwave of OPs (oscillatory potentials) was highest in 846 composition group and lowest in pentobarbitone group. The amplitude of b-wave of phot-ERG (photo...