Cor Vasa 2005, 46(7-8):283-288

Experimental pulmonary embolism (PE) did not change brain natriuretic peptide (BNP) levels in a rat model

Peter Scheer^1,*, Petr Svoboda², Dita Kosáková¹, Jozef Tomandl³, Jaroslav Doubek¹

¹ Ústav fyziologie, Fakulta veterinárního lékařství, Veterinární a farmaceutická univerzita Brno

² Úrazová nemocnice Brno

³ Biochemický ústav, Lékařská fakulta Masarykovy univerzity, Brno, Česká republika

Aims:
The aim of this study was to investigate the plasma levels of rat BNP-32 at 60 minutes after pulmonary embolism (PE) induction in an newly developed animal model of sublethal massive non-thrombotic acute PE, and to describe alterations in the evaluated clinical parameters.

Material and methods:
Thirty nine (male, outbreed, 480-530 g) Wistar rats were randomized into two groups: PE (pure non-thrombotic acute massive PE induced by intravenous administration of 2 ml of the microsphere suspension Embo-sphere 40-120 mm; n = 23) and a control group (C; sham procedure, 2 ml of isotonic saline solution; n = 16). Sixty min-utes after PE induction, arterial blood was sampled in both groups (carotid artery) for BNP analysis. An EIA rat BNP-32 set (Phoenix Peptide Inc.) was used for the analysis. The experimental protocol was performed under general anesthesia.

Results:
Mean plasma BNP level in the PE group 1.37; SD 0.30 ng/l did not differ significantly from that in the control group 1.14 ± 0.37 ng/L (p = 0.21). Heart rates were significantly lower in the PE group at 30 (281 ± 50 min vs. 312 ± 58/min; p = 0.005) and 50 min (264 ± 60/min vs. 306 ± 77/min, p = 0.005) when compared with the control group. Sp O2 values were significantly lower in the PE group at 30 (86 ± 6% vs. 91 ± 4%; p = 0.004) and at 50 min (89 ± 6 vs. 93 ± 4; p = 0.01. In the PE group, the respiratory rate was significantly elevated at only 30 mins (81 ± 16/min vs. 69 ± 8 /min; p = 0.048).

Conclusion:
We have developed a new hemodynamically stable animal model of non-thrombotic acute pulmonary embolism. In this rat model, acute pure non-thrombotic pulmonary embolism did not change the plasma levels of BNP sampled at 60 minutes after PE induction. Pulmonary embolism resulted in a significant decrease of Sp O2 and heart rate, whilst respiratory rate increased.

Keywords: Rat; Pulmonary embolism; Natriuretic peptide; BNP

Published: July 1, 2005  Show citation