Affordable Access

Sympathetic beta-agonists and cochlear blood flow in guinea pigs.

Authors
  • Kobayashi, N
  • Hasegawa, M
  • Yokoyama, K
  • Tamura, T
Type
Published Article
Journal
The Journal of otolaryngology
Publication Date
Apr 01, 1994
Volume
23
Issue
2
Pages
97–101
Identifiers
PMID: 8028080
Source
Medline
License
Unknown

Abstract

The effects of sympathetic beta-agonists on blood pressure and cochlear blood flow were studied in 15 guinea pigs. Cochlear blood flow was measured by a laser Doppler flowmeter, Periflux PF2 (Perimed, Sweden). Small doses (0.01 and 0.1 microgram/kg) of isoproterenol elevated blood pressure, but larger doses (10 and 50 micrograms/kg) decreased blood pressure. Cochlear blood flow showed a biphasic pattern, in that there was an initial decrease with a subsequent increase. Dobutamine, a beta 1-agonist, elevated blood pressure and increased cochlear blood flow in a dose-dependent manner. Salbutamol, a beta 2-agonist, decreased blood pressure in a dose-dependent manner and induced a biphasic pattern of changes (i.e., an initial decrease with a subsequent increase). The effect of isoproterenol, which is a nonselective beta-agonist, is oriented more to a beta 2-agonist at larger doses. These different effects induced by isoproterenol are probably due to a balance of dominance between beta 1 action and beta 2 action at different doses.

Report this publication

Statistics

Seen <100 times