To investigate the blood pressure levels, cognitive function, and gut microbiota characteristics of middle-aged spontaneously hypertensive rats (SHR).
SHR and its control rats WKY aged 13 weeks were purchased and randomly divided into 4 groups, namely SHR male group (n=6), SHR female group (n=8), WKY male group (n=6) and WKY female group (n=8). After 26 weeks of feeding, the blood pressure level of the rats was measured by tail pressure method, and the autonomous activity ability of the rats was observed by open field experiment. The Morris water maze experiment was used to observe the learning and cognitive function of rats. After the experiment, the stool of rats was collected, and the intestinal flora characteristics of rats were analyzed by 16SrRNA sequencing.
The systolic blood pressure of male and female rats in SHR group was significantly higher than that in WKY group (all P<0.01). The results of open field test showed that the average speed of SHR female rats was higher than that of WKY male rats (P<0.001), while the residence time in the surrounding area of WKY female rats was higher than that of WKY male rats (P<0.05). The results of water maze test showed that the latency time of SHR during training decreased more than that of WKY, and the latency time of WKY female rats during testing was higher than that of SHR male and female rats (P<0.01; P<0.001). Beta diversity analysis showed that there were significant differences in the structure of intestinal flora among the four groups of rats (R=0.627 5, P=0.001), and the relative abundance of Firmicutes and Turicibacter was increased in SHR males, while that of Bacteroidota and norank_f_Muribaculaceae was increased in WKY males (all P<0.05). Correlation analysis revealed significant associations between the relative abundance of certain gut microbiota and blood pressure as well as behavioral indicators in SHR and WKY rats of different genders.
There are significant gender differences in blood pressure levels, cognitive function, and gut microbiota characteristics among middle-aged SHR rats. The elevated blood pressure and hyperactivity characteristics are more pronounced in female rats, while the abnormal gut microbiota composition is more prominent in male rats. This suggests that gender differences should be considered in studies related to hypertension and gut microbiota.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |