Neurotransmitters and stimulation of fluid reabsorption in migratory locust rectal cells.
Several biogenic amines enhance fluid reabsorption and the accumulation of cyclic adenosine-monophosphate (cAMP) in the rectum of the migratory locust but only 5-hydroxytryptamine (5-HT) acts in a dose-dependent manner at low concentrations (between 10(-8) and 5.10(-7) M). Cyclic AMP is a second messenger of 5-HT, and its actions on fluid reabsorption are calcium-dependent. Polymyxin B (a protein kinase C inhibitor) mimics the actions of 5-HT on fluid reabsorption and on calcium-dependent cAMP accumulation. This suggests the presence of other sources of calcium and a possible relationship between several transduction systems within different rectal cells. The second messenger system mediating the 5-HT antidiuretic message differs from those involved in the transduction of the known locust antidiuretic hormones.
Fournier
B
B
Laboratoire de Neuroendocrinologie, URA CNRS 1138, Université de Bordeaux I, Talence, France.
Viratelle
O
O
Hamoudi
N
N
Proux
J
J
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000042:Absorption; D000818:Animals; D001834:Body Water / Q000378:metabolism*; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006110:Grasshoppers / Q000378:metabolism*; D008297:Male; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D011112:Polymyxin B / Q000494:pharmacology; D011863:Radioimmunoassay; D012007:Rectum / Q000187:drug effects / Q000378:metabolism; D012701:Serotonin / Q000494:pharmacology
D018377:Neurotransmitter Agents; D012701:Serotonin; D000001:Calcimycin; D000242:Cyclic AMP; D011112:Polymyxin B; D002118:Calcium; D015056:1-Methyl-3-isobutylxanthine