Central effects of various ligands on drinking behavior in eels acclimated to seawater.
Intracranial injection of eel angiotensin II (eANG II, 5x10(-13)-5x10(-8) mol), acetylcholine (ACh, 5x10(-12)-5x10(-9) mol), substance P (5x10(-10) mol) and isoproterenol (a beta-adrenoceptor agonist, 5x10(-11)-5x10(-9) mol) enhanced water intake in the seawater eel. The effects of eANG II, ACh and isoproterenol were dose-dependent. By contrast, water intake was inhibited by intracranial injection of eel atrial natriuretic peptide (eANP, 5x10(-13)-5x10(-10) mol), serotonin (5-HT, 5x10(-12)-5x10(-8) mol), ghrelin (5x10(-12)-5x10(-10) mol), gamma-amino butyric acid (GABA, 5x10(-11)-5x10(-8) mol), prolactin (PRL, 5x10(-10)-5x10(-9) mol), arginine vasotocin (AVT, 5x10(-12) mol), vasoactive intestinal peptide (VIP, 5x10(-11) mol), noradrenaline (5x10(-9) mol l(-1)) and phenylephrine (alpha-adrenoceptor agonist, 5x10(-11)-5x10(-9) mol). The inhibitory effects of eANP, 5-HT, ghrelin, GABA, PRL and phenylephrine were dose-dependent. The intracranial stimulatory effect of eANG II was relatively long-lasting compared with the intravenous effect. The stimulatory effect of intravenous eANG II disappeared immediately, and was followed by an inhibition, which could be well explained by an increase in eANP secretion from the atrium.
Kozaka
Tomohiro
T
Laboratory of Integrative Physiology, Faculty of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan.
Fujii
Yasuaki
Y
Ando
Masaaki
M
D000064:Acclimatization / Q000502:physiology*; D000109:Acetylcholine / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology; D004327:Drinking Behavior / Q000187:drug effects / Q000502:physiology*; D004524:Eels / Q000502:physiology*; D054439:Ghrelin; D007545:Isoproterenol / Q000494:pharmacology; D008024:Ligands; D036361:Peptide Hormones / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D011388:Prolactin / Q000494:pharmacology; D012623:Seawater; D012701:Serotonin / Q000494:pharmacology; D013373:Substance P / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology; D014668:Vasotocin / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D054439:Ghrelin; D008024:Ligands; D036361:Peptide Hormones; D000804:Angiotensin II; D010656:Phenylephrine; D012701:Serotonin; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D005680:gamma-Aminobutyric Acid; D009320:Atrial Natriuretic Factor; D011388:Prolactin; D007545:Isoproterenol; D000109:Acetylcholine; D014668:Vasotocin