Coal Worker's Pneumoconiosis Cases Of Learning And Memory In Rats And The Biochemical Mechanism Invloved

Backgroud:Coal worker's pneumoconiosis (coal workers'pneumoconiosis, CWP) is caused by coal mine workers from inhaling dust to diffuse lung lesions consisting mainly of fibrous pneumoconiosis. It is one of the serious threat to our common occupational diseases in the health of workers. Since the eighties, the emergence of a number of private small-scale coal mines, backward production methods, occupational diseases prevention and control input factors such as inadequate and ineffective supervision, so that China's coal worker's pneumoconiosis showed increasing trends in incidence rates. The pathogenesis of the disease has not yet been fully clarified, and because of chronic hypoxia on long-term damage to brain function is gradually cause for concern. The relationship of learning and memory with the central cholinergic has been accepted generally. In recent years, insulin-like growth factor-1 in the role of learning and memory is also increasingly a cause for concern. Human insulin-like growth factor-I is a multi-peptide, produced by the liver, into the blood through the blood-brain barrier, and distributed in the brain tissue of IGF-I receptor binding in the brain play an important biological effects, such as:to reduce the loss of damaged neurons, regulating the synthesis and release of acetylcholine, etc. Past studies have shown that hypoxia can affect the serum IGF-1 levels, but coal worker's pneumoconiosis serum IGF-1 levels and the relationship between brain cholinergic activity not relevant reports. In order to understand cognition in patients with coal worker's pneumoconiosis on the impact and the related biochemical mechanism for the prevention and treatment of clinical disease and related diseases to provide the necessary experimental basis for the mechanism, this study through the establishment of rat CWP model, using Morris water maze test to observe the learning and memory ability and enzyme-linked immunosorbent assay of serum IGF-1 levels, measured by colorimetry ChAT activity in rat brain.Objectives:Through the Morris water maze test understanding of coal worker's pneumoconiosis cases of learning and memory in rats, serum IGF-1 levels and ChAT activity of brain tissue to study the coal worker's pneumoconiosis caused by decline in learning and memory possible mechanisms with a view to coal worker's pneumoconiosis Clinical prevention and treatment, as well as the pathogenesis of related diseases to provide the necessary experimental basis.Methods:Twenty-seven healthy 3-month-old Wistar rats (Hebei Medical College provided) 45, both male, weight 180～200g, all rats were treated with the same kinds of dry feed, feeding, drinking ordinary tap water at room temperature controlled at 25±1℃. After the adaptive feeding of 1 week, the rats were randomly divided into 3 groups, namely, control group 20, model group 20, pre-experimental group 5. Then the model group and pre-experimental rats directly tracheal intubation, poured into the corresponding saline suspension of coal dust 1ml. Poured into the normal saline control group processing. Experimental period is 8 weeks. In the experiment the first 8 weeks, the pre-experimental group of five rats takes the blood-gas analysis, measure arterial oxygen pressure and blood oxygen saturation and put rat lung tissue biopsies obtained HE staining to observe pathological changes. Then 10 rats randomly selected in the model group and 10 rats randomly selected in the control group have been observed the learning and memory ability through the Morris water maze test.Measure IGF-1 levels in the serum through the enzyme-linked immunosorbent assay and ChAT activity in rat brain tissueby through the colorimetry.Results:1, Learning outcomes:after 5 days training, escape latency in the model group is longer than the one in the control group.There is significant difference between the two groups (p<0.05). Compared with the control group, the number of cross platform in the model group is significantly reduced (p<0.01); Compared with the control group, the percentage of crossing the target quadrant time in the total swimming time is significantly reduced (p<0.01).2, ChAT activity of rat's brain tissue in the model is significantly lower than the one in the control group (P<0.001).3, Serum IGF-1 in the model group is significantly lower than the one in the control group (p<0.001), and IGF-I in rat serum and ChAT activity in rat brain was positively correlated.Conclusions:1. Coal worker's pneumoconiosis impaired learning and memory in rats.2. Coal worker's pneumoconiosis caused ChAT activity which led to impaired learning and memory decreased in the rat brain,3. Coal worker's pneumoconiosis caused IGF-I in rat serum reduced, and IGF-I in rat serum and ChAT activity in rat brain was positively correlated.