Experimental method for verifying curative effect of retinoic acid on schizophrenia

Abstract

The invention provides an experimental method for verifying the curative effect of retinoic acid on schizophrenia, which comprises the following steps: step 1, selecting two groups of pregnant SD rats, injecting Poly I: C into tail veins of one group of SD rats after 9.5 days of pregnancy according to the standard of 10 mg / kg, and taking male offspring rats as schizophrenia model group rats; the other group of SD rats are intravenously injected with equal-volume normal saline at the tail after pregnancy 9.5 days, and the male offspring rats are the control group; 2, the model components are divided into two groups, retinoic acid is fed to one group 45 days after birth according to the standard of 3 mg / kg / day, an equal amount of placebo is injected to the other group, and an equal amount of placebo is injected to the control group; step 3, carrying out behavioral detection experiments on the three groups of rats in the step 2; and 4, implanting electrodes into hippocampal CA1 regions of the three groups of rats in the step 2, and recording and analyzing electroencephalogram activities of the three groups of rats. The experimental method provided by the invention proves that the retinoic acid has good application value in preparation of the schizophrenia medicine.

Description

Technical Field

[0001] The invention belongs to the technical field of psychiatric disease drug research, and specifically relates to an experimental method for verifying the efficacy of retinoic acid in treating schizophrenia. Background Art

[0002] Schizophrenia patients have various clinical symptoms, including positive symptoms, negative symptoms, and cognitive impairment. Existing antipsychotic drugs can significantly improve patients' positive symptoms, but the improvement effect on negative symptoms and cognitive impairment is not ideal. Negative symptoms and cognitive impairment are the fundamental factors that hinder the recovery of patients' social functions, and drug development for them is an important issue that needs to be solved urgently.

[0003] Earlier, when I was preparing a rat model of schizophrenia, I found that the model rats had a deficiency of retinoic acid (RA). Based on the extensive biological effects of retinoic acid on the nervous system, I further designed experiments to confirm that retinoic acid supplementation can significantly improve the multi-dimensional behavioral abnormalities and EEG signal abnormalities in schizophrenia model rats. Summary of the invention

[0004] The purpose of the present invention is to provide an experimental method for verifying the efficacy of retinoic acid in treating schizophrenia in view of the deficiencies of the prior art. The specific scheme is as follows: The experimental method for verifying the efficacy of retinoic acid in treating schizophrenia is characterized by comprising the following steps: Step 1, two groups of normally pregnant SD rats were selected, one group of SD rats was injected with Poly I:C at the tail vein according to the standard of 10 mg / kg at 9.5 days of pregnancy, the offspring were weaned 21 days after birth, and the male offspring rats were selected as the schizophrenia model group rats; the other group of SD rats was injected with an equal volume of normal saline at 9.5 days of pregnancy, the offspring were weaned 21 days after birth, and the male offspring rats were selected as the control group; Step 2: Divide the model group into two groups, one of which is given retinoic acid at 3 mg / kg / day after 45 days of birth, and the other is injected with an equal amount of placebo, and the control group is given an equal amount of placebo; Step 3, conducting behavioral testing experiments on the three groups of rats in step 2, and recording and analyzing the experimental results; Step 4: implant electrodes into the CA1 region of the hippocampus of the three groups of rats in step 2, record and analyze the EEG activities of the three groups of rats, and analyze the effects of retinoic acid intervention on the neural activities of the schizophrenia model.

[0005] Based on the above, the behavioral testing experiments in step 3 include social experiments, cross elevated experiments and prepulse inhibition testing experiments.

[0006] Based on the above, the behavioral testing time for rats in step 3 is 60 days after birth.

[0007] The present invention has prominent substantive features and remarkable progress compared with the prior art. Specifically, the present invention has the following advantages: Through experimental analysis, it can be seen that after retinoic acid intervention, the schizophrenia-like behaviors of rats in the schizophrenia model group, such as social deficits, anxiety, and cognitive impairment, have improved significantly. These symptoms correspond to the negative symptoms, positive symptoms, and cognitive impairment in clinical practice, suggesting that retinoic acid has good application value in the preparation of schizophrenia drugs. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a comparative analysis diagram of the control group rats, the model group rats, and the improvement of the behavior of the model group rats by retinoic acid intervention; among them Figure 1 A is the experimental flow chart. Two groups of SD rats were injected with Poly I:C and normal saline respectively via the tail vein at a standard of 10 mg / kg on the 9.5th day of pregnancy. The offspring were weaned at 21 days after birth. The male offspring were selected and defined as the model group and the control group respectively. The model group was divided into two groups. One group of model group rats was given retinoic acid at a standard of 3 mg / kg / day from P45 days, and the other group of model group rats and the control group rats were given an equal amount of placebo treatment. Behavioral detection experiments were carried out at P60 days for evaluation and analysis; Figure 1 B is the social experiment, showing that retinoic acid intervention can improve the social ability of the model group rats; Figure 1 C is the elevated plus maze experiment, showing that retinoic acid intervention can improve the anxiety of the model group rats; Figure 1 D is the prepulse inhibition experiment, showing that retinoic acid intervention can improve the PPI level of the model rats, suggesting that the sensory gating function of the rats after retinoic acid treatment has been improved; Figure 2 Comparative analysis diagram of the electroencephalogram signals of the control group rats, the model group rats, and the improvement of the model group rats by retinoic acid intervention; Figure 2 A is the electrode position diagram; Figure 2 B is the time-frequency diagram of the field potential; Figure 2 C is the power spectrum-energy diagram of the field potential; Figure 2 D is the energy diagram of signals in different frequency bands, and the results show that retinoic acid intervention can significantly improve the abnormal field potential of the model rats. DETAILED DESCRIPTION OF THE INVENTION

[0009] The technical solutions of the present invention will be further described in detail below through specific embodiments. Embodiment

[0010] As Figure 1-2 shown, the present invention provides an experimental method for verifying the efficacy of retinoic acid in the treatment of schizophrenia, which is characterized by including the following steps: Step 1: Select two groups of normally pregnant SD rats. One group of SD rats was intravenously injected with Poly I:C at the standard of 10 mg / kg through the tail vein on the 9.5th day of pregnancy. The offspring were weaned 21 days after birth, and the male offspring rats were used as the schizophrenia model group rats. Another group of SD rats was intravenously injected with an equal amount of normal saline on the 9.5th day of pregnancy. The offspring were weaned 21 days after birth, and the male offspring rats were used as the control group. Step 2: Divide the model group into two groups. One group was given retinoic acid at the standard of 3 mg / kg per day 45 days after birth, and the other group was injected with an equal amount of placebo. The control group was injected with an equal amount of placebo. Step 3: Conduct behavioral detection experiments on the three groups of rats in Step 2 60 days after birth, and record and analyze the experimental results. Step 4: Implant electrodes in the hippocampal CA1 region of the three groups of rats that completed the behavioral tests, and record and analyze the electroencephalogram activities of the three groups of rats to analyze the effect of retinoic acid intervention on the neural activities of the schizophrenia model.

[0011] The behavioral detection experiments in Step 3 above include social experiments, plus-maze experiments, and prepulse inhibition experiments.

[0012] The time for behavioral detection of rats in Step 3 above is 60 days after birth.

[0013] Figure 1 It is a comparative analysis chart of the control group rats, the model group rats, and the improvement of the behavior of the model group rats by retinoic acid intervention; among them Figure 1 A is the experimental flow chart. Two groups of SD rats were intravenously injected with Poly I:C and normal saline at the standard of 10 mg / kg through the tail vein on the 9.5th day of pregnancy. The offspring were weaned 21 days after birth. The male offspring were selected and defined as the model group and the control group respectively. The model group was divided into two groups. One group of model group rats was given retinoic acid at the standard of 3 mg / kg per day since P45 days, and the other group and the control group rats were treated with an equal amount of placebo. Behavioral detection experiments were conducted and evaluated and analyzed at P60 days. Figure 1 B is the social experiment, showing that retinoic acid intervention can improve the social ability of the model group rats. Figure 1 C is the plus-maze experiment, showing that retinoic acid intervention can improve the anxiety of the model group rats. Figure 1 D is the prepulse inhibition experiment, showing that retinoic acid intervention can improve the PPI level of the model rats, indicating that the sensory gating function of the rats after retinoic acid treatment is improved. Figure 2 Comparative analysis chart of the electroencephalogram signals of the control group rats, the model group rats, and the improvement of the model group rats by retinoic acid intervention; Figure 2 A is the electrode position map; Figure 2 B is the time-frequency map of the field potential; Figure 2 C is the power spectrum-energy map of the field potential;Figure 2 D is the energy map of signals in different frequency bands, and the results show that retinoic acid intervention can significantly improve the abnormal field potential of model rats.

[0014] Through experimental analysis, it can be seen that after retinoic acid intervention, the symptoms of schizophrenia in the model group of rats, such as social deficit, anxiety, and cognitive impairment, have improved significantly. These symptoms correspond to the negative symptoms, positive symptoms, and cognitive impairment in clinical practice, indicating that retinoic acid has good application value in the preparation of drugs for schizophrenia.

[0015] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that it is still possible to modify the specific implementation manners of the present invention or perform equivalent replacements for some technical features; without departing from the spirit of the technical solutions of the present invention, they should all be covered by the scope of the technical solutions claimed by the present invention.

Claims

1. An experimental method for verifying the efficacy of retinoic acid in the treatment of schizophrenia, characterized in that It includes the following steps: Step 1: Select two groups of SD rats with normal pregnancy. Among them, on the 9.5th day of pregnancy, one group of SD rats was injected with Poly I:C via the caudal vein at a standard of 10 mg / kg. The offspring were weaned 21 days after birth, and male offspring rats were selected as the schizophrenia model group rats; in the other group, SD rats were injected with an equal volume of normal saline on the 9.5th day of pregnancy. The offspring were weaned 21 days after birth, and male offspring rats were selected as the control group; Step 2: Divide the model group into two groups. Among them, one group was given retinoic acid at a standard of 3 mg / kg / day 45 days after birth, and the other group was injected with an equal amount of placebo, and the control group was injected with an equal amount of placebo; Step 3: Conduct behavioral detection experiments on the three groups of rats in Step 2, and record and analyze the experimental results; Step 4: Implant electrodes into the CA1 area of the hippocampus of the three groups of rats in Step 2, record and analyze the electroencephalogram activities of the three groups of rats, and analyze the influence of retinoic acid intervention on the neural activities of the schizophrenia model.

2. The experimental method for verifying the efficacy of retinoic acid in the treatment of schizophrenia according to claim 1, characterized in that: The behavioral detection experiments in Step 3 include social experiments, plus maze experiments, and prepulse inhibition detection experiments.

3. The experimental method for verifying the efficacy of retinoic acid in the treatment of schizophrenia according to claim 1, characterized in that: The time for behavioral detection of rats in Step 3 is 60 days after birth.

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