Effect of injection of different doses of isoproterenol on the hearts of mice

Abstract

Background: Heart failure (HF) is one of the diseases that seriously threaten human health today and its mechanisms are very complex. Our study aims to confirm the optimal dose ISO-induced chronic heart failure mice model for better study of HF-related mechanisms and treatments in the future.

Methods: C57BL/6 mice were used to establish mice model of chronic heart failure. We injected isoproterenol subcutaneously in a dose gradient of 250 mg/kg, 200 mg/kg, 150 mg/kg, 100 mg/kg and 50 mg/kg. Echocardiography and ELISA were performed to figure out the occurrence of HF. We also supplemented the echocardiographic changes in mice over 30 days.

Results: Except group S and group E, echocardiographic abnormalities were found in other groups, suggesting a decrease in cardiac function. Except group S, myofibrolysis were found in the hearts of mice in other groups. Brain natriuretic peptide was significantly increased in groups B and D, and C-reactive protein was significantly increased in each group.

Conclusion: Our research finally found that the HFrEF mice model created by injection at a dose of 100 mg/kg for 7 days was the most suitable and a relatively stable chronic heart failure model could be obtained by placing it for 21 days.

Keywords: Animal model; Dosage standards; Heart failure; Isoproterenol; Modeling success criteria.

Fig. 1

The figure showing the EF before administration (Red), EF of dosing for 7 days (Blue) and EF after 21 days (Green) in groups

Fig. 2

Bar graphs showing the EF before administration (A), EF after dosing for 7 days (B), EF after 21 days (C). (D)Echocardiogram showing FS and EF at 3 times in each group. Data shown are means ± SD; n = 6 in each group. *P < 0.05, significantly different as indicated

Fig. 3

The figure showing the HR before administration (Blue bar graph), HR of dosing for 7 days (Red bar graph) and HR after 21 days (Green bar graph) in groups

Fig. 4

Bar graphs showing the HR before administration (A), HR after dosing for 7 days (B), HR after 21 days (C). (D) Echocardiogram showing HR at 3 times in each group. Data shown are means ± SD; n = 6 in each group. *P < 0.05,significantly different as indicated

Fig. 5

Graph showing changes in EF over days. Data shown are means ± SD; n = 6 in each group. The red line represents Group A, the blue line represents Group B, the green line represents Group C, the yellow line represents Group D, and the purple line represents Group E. Group S was not recorded in this experiment

Fig. 6

Graph showing changes in FS over days. Data shown are means ± SD; n = 6 in each group. The red line represents Group A, the blue line represents Group B, the green line represents Group C, the yellow line represents Group D, and the purple line represents Group E. Group S was not recorded in this experiment

Fig. 7

Graph showing changes in EF over days. Data shown are means ± SD; n = 6 in each group. The red line represents Group A, the blue line represents Group B, the green line represents Group C, the yellow line represents Group D, and the purple line represents Group E. Group S was not recorded in this experiment

Fig. 8

Bar graph showing BNP levels in different groups. Data shown are means ± SD; n = 6 in each group. *P < 0.05, significantly different as indicated

Fig. 9

Bar graph showing CRP levels in different groups.Data shown are means ± SD; n = 6 in each group. *P < 0.05, significantly different as indicated

Fig. 10

The figure showing the FS before administration (Blue), FS of dosing for 7 days (Red) and FS after 21 days (Green) in groups

Fig. 11

Bar graphs showing the FS before administration(A), FS after dosing for 7 days(B), FS after 21 days(C). Data shown are means ± SD; n = 6 in each group. *P < 0.05, significantly different as indicated

Fig. 12

Representative images of HE staining showing changes in inflammatory cells in cardiac sections from each group of mice. Green arrows indicate exceptions