TY - JOUR
T1 - Antidipsogenic effects of eel bradykinins in the eel Anguilla japonica
AU - Takei, Yoshio
AU - Tsuchida, Takamasa
AU - Li, Zhihong
AU - Conlon, J. Michael
PY - 2001
Y1 - 2001
N2 - A peptide with bradykinin (BK)-like immunoreactivity was isolated from an incubate of heat-denatured eel plasma with porcine pancreatic kallikrein. The purified peptide had the following amino acid sequence: Arg-Arg-Pro-Pro-Gly-Ser-Trp-Pro-Leu-Arg. This decapeptide, named eel [Arg0]BK, was identical to two previously identified BK homologs from cod and trout. High conservation of the BK sequence among distant teleost species suggests an important function in this vertebrate group. Bolus intra-arterial injections of eel [Arg0]BK, BK, and [Arg0]-des-Arg9-BK (1-10 nmol/kg) caused significant (P<0.05) inhibition of drinking in seawater-adapted eels. The potency of the inhibition was ranked in the following order: [Arg0]BK>[Arg0]-des-Arg9-BK=BK. The BK peptides also produced an immediate, transient increase followed by a sustained increase in arterial blood pressure and an initial decrease followed by an increase in heart rate. Strong tachyphylaxis occurred for the cardiovascular effect but not for the antidipsogenic effect. The order of the potency of the cardiovascular actions, [Arg0]BK>BK>[Arg0]-des-Arg9-BK, was different from that of the antidipsogenic action. Slow infusions of eel [Arg0]BK in the dose range 1-1,000 pmol·kg-1·min-1 produced concentration-dependent inhibition of drinking without changes in arterial pressure, plasma osmolality, and hematocrit. At the infusion rate of >100 pmol·kg-1·min-1, plasma concentrations of angiotensin II, a potent dipsogenic hormone in eels, increased, suggesting an interaction of the kallikrein-kinin and reninangiotensin systems. In mammals, BK is dipsogenic and vasodepressor, so that our data demonstrate opposite effects on fluid and cardiovascular regulation of BK in the eel and suggest a new physiological role for the kallikrein-kinin system in teleost fish.
AB - A peptide with bradykinin (BK)-like immunoreactivity was isolated from an incubate of heat-denatured eel plasma with porcine pancreatic kallikrein. The purified peptide had the following amino acid sequence: Arg-Arg-Pro-Pro-Gly-Ser-Trp-Pro-Leu-Arg. This decapeptide, named eel [Arg0]BK, was identical to two previously identified BK homologs from cod and trout. High conservation of the BK sequence among distant teleost species suggests an important function in this vertebrate group. Bolus intra-arterial injections of eel [Arg0]BK, BK, and [Arg0]-des-Arg9-BK (1-10 nmol/kg) caused significant (P<0.05) inhibition of drinking in seawater-adapted eels. The potency of the inhibition was ranked in the following order: [Arg0]BK>[Arg0]-des-Arg9-BK=BK. The BK peptides also produced an immediate, transient increase followed by a sustained increase in arterial blood pressure and an initial decrease followed by an increase in heart rate. Strong tachyphylaxis occurred for the cardiovascular effect but not for the antidipsogenic effect. The order of the potency of the cardiovascular actions, [Arg0]BK>BK>[Arg0]-des-Arg9-BK, was different from that of the antidipsogenic action. Slow infusions of eel [Arg0]BK in the dose range 1-1,000 pmol·kg-1·min-1 produced concentration-dependent inhibition of drinking without changes in arterial pressure, plasma osmolality, and hematocrit. At the infusion rate of >100 pmol·kg-1·min-1, plasma concentrations of angiotensin II, a potent dipsogenic hormone in eels, increased, suggesting an interaction of the kallikrein-kinin and reninangiotensin systems. In mammals, BK is dipsogenic and vasodepressor, so that our data demonstrate opposite effects on fluid and cardiovascular regulation of BK in the eel and suggest a new physiological role for the kallikrein-kinin system in teleost fish.
KW - Cardiovascular effects
KW - Drinking behavior
KW - Kallikrein-kinin system
KW - Renin-angiotensin system
KW - Teleost fish
UR - http://www.scopus.com/inward/record.url?scp=0034785781&partnerID=8YFLogxK
U2 - 10.1152/ajpregu.2001.281.4.r1090
DO - 10.1152/ajpregu.2001.281.4.r1090
M3 - Article
C2 - 11557614
AN - SCOPUS:0034785781
SN - 0363-6119
VL - 281
SP - R1090-R1096
JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
IS - 4 50-4
ER -