Effects of Angiotensin-converting Enzyme Inhibitors and Angiotensin II Receptor Blockers on the Immune System of Pseudomonas aeruginosa Challenged Hamsters

The severe cases of coronavirus disease 2019 observed in patients with hypertension and diabetes mellitus disease have created controversy as to why this was the case and the role of angiotensin receptor blockers (ARBs) and angiotensin enzyme inhibitors was not ruled out as a contributing factor. The objective of this study was to investigate the effects of angiotensin converting enzyme inhibitors (ACEIs) and ARBs on respiratory immunity. The study used a Syrian hamster as an animal model to study the effects of ARBs and ACEIs on the immune system of Pseudomonas aeruginosa-challenged hamsters; fever was a response variable. The hamsters were randomly separated into three groups of six. One group was administered enalapril, another with losartan, and the last group was administered water for 30 days. After 30 days, the hamsters were inoculated with 0.2 mL of 1.5 × 108 cfu/mL of P. aeruginosa. After 18 h from the inoculation time, the temperature was taken every 2 h for 36 h. The temperature in all groups ranged from 35.5°C to 37.2°C with an average of 36.1°C and there was no mortality recorded at the end of 14 days. The results were analyzed using Dunnett multiple comparisons analysis of variance using Statistical Package for the Social Sciences version 27. There were no significant differences in temperature between hamsters treated with enalapril or losartan and those treated with water (control). In addition, no hamster developed fever. In conclusion, enalapril and losartan may not negatively affect the respiratory immunity. Effects of ACEIs and ARBs on the immune system of P. aeruginosa challenged hamsters