We tested the hypothesis that exogenous substance P (SP) could enhance rat aortic permeability to plasma albumin. Fluorescein-labeled bovine serum albumin was used as the tracer. In vivo normalized albumin mass transfer rates (x10-8 cm/sec) were 9.16 ± 1.73, 14.20 ± 2.76 (P < 0.05) and 20.31 ± 3.31 (P < 0.001) for groups infused i.v. with 0.01 N acetic acid vehicle, 7.4 pmol and 0.74 pmol SP/kg/min for 5 min, respectively. No significant differences from the control group were found in rats receiving 150 pmol, 74 pmol nor 74 fmol SP/kg/min for 5 min. The results indicate that aortic permeability dynamics for plasma albumin can be enhanced by pmol levels of the tachykinin SP.
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Pharmacology, Toxicology and Pharmaceutics(all)