A C-terminal aldehyde analog of the insect kinins inhibits diuresis in the housefly.
The insect kinins are present in a wide variety of insects and function as potent diuretic peptides in flies. A C-terminal aldehyde insect kinin analog, Fmoc-RFFPWG-H (R-LK-CHO), demonstrates stimulation of Malpighian tubule fluid secretion in crickets, but shows inhibition of both in vitro and in vivo diuresis in the housefly. R-LK-CHO reduced the total amount of urine voided over 3 h from flies injected with 1 microL of distilled water by almost 50%. The analog not only inhibits stimulation of housefly fluid secretion by the native kinin Musdo-K, but also by thapsigargin, a SERCA inhibitor, and by ionomycin, a calcium ionophore. The activity of R-LK-CHO is selective, however, as related C-terminal aldehyde analogs do not demonstrate an inhibitory response on housefly fluid secretion. The selective inhibitory activity of R-LK-CHO on housefly tubules represents an important lead in the development of environmentally friendly insect management agents based on the insect kinins.
Nachman
Ronald J
RJ
Areawide Pest Management Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX 77845, USA. nachman@tamu.edu
Fehrentz
Jean-Alain
JA
Martinez
Jean
J
Kaczmarek
Krzyztof
K
Zabrocki
Janusz
J
Coast
Geoffrey M
GM
D000447:Aldehydes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D004231:Diuresis / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006793:Houseflies / Q000187:drug effects* / Q000378:metabolism; D007705:Kinins / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*
D000447:Aldehydes; D007705:Kinins