Extracts of the brain/corpora cardiaca/corpora allata (Br/CC/CA) complex of Manduca sexta larvae elicit an antidiuretic effect, measured by an increase in fluid reabsorption across the cryptonephric complex of larval M. sexta. Separation of the extract by reversed-phase liquid chromatography gave two fractions with antidiuretic effects. The more potent of these two factors was further characterized for its effects on the cryptonephric complex. Its antidiuretic effect is not inhibited by bumetanide, a drug that inhibits M. sexta diuretic hormone (Mas-DH)-stimulated fluid reabsorption. These data indicate that the mechanism of the antidiuretic effect of the factor is different from that of Mas-DH on the cryptonephric complex. The basal reabsorption of the cryptonephric complex is blocked when treated on the lumen side with bafilomycin A(1), an inhibitor of the H(+)-ATPase, or with amiloride, an inhibitor of the H(+)/K(+) antiporter. However, the antidiuretic-factor-stimulated fluid reabsorption is not affected by either bafilomycin A(1) or amiloride. The increase in reabsorption triggered by the semi-purified factor can be inhibited by Cl(−) channel blockers or by removing Cl(−) from the lumen side of the cryptonephric complex. It appears that this factor activates a Cl(−) pump associated with the cryptonephric complex. Forskolin mimics the effect of this factor on fluid reabsorption, and the effect of forskolin is not inhibited by bumetanide. A selective and potent inhibitor of protein kinase A, H-89, also inhibits antidiuretic-factor-stimulated fluid reabsorption. Addition of the factor to cryptonephric complexes maintained in vitro caused a significant increase in cyclic AMP levels extracted from these tissues compared with values for controls. These data suggest that the antidiuretic effect of the factor in Br/CC/CA extract is mediated by cyclic AMP.

Audsley
N.
,
Kay
I.
,
Hayes
T. K.
,
Coast
G. M.
(
1995
).
Cross reactivity studies of CRF-related peptides on insect Malpighian tubules
.
Comp. Biochem. Physiol
110
,
87
–.
Audsley
N.
,
McIntosh
C.
,
Phillips
J. E.
(
1992
).
Isolation of a neuropeptide from locust corpus cardiacum which influences ileal transport
.
J. Exp. Biol
173
,
261
–.
Audsley
N.
,
Phillips
J. E.
(
1990
).
Stimulants of ileal salt transport in neuroendocrine system of the desert locust
.
Gen. Comp. Endocr
80
,
127
–.
Blackburn
M. B.
,
Kingan
T. G.
,
Bodnar
W.
,
Shabanowitz
J.
,
Hunt
D. F.
,
Kempe
T.
,
Wagner
R. M.
,
Raina
A. K.
,
Schnee
M. E.
,
Ma
M. C.
(
1991
).
Isolation and identification of a new diuretic peptide from the tobacco hornworm, Manduca sexta
.
Biochem. Biophys. Res. Commun
181
,
927
–.
Blackburn
M. B.
,
Ma
M. C.
(
1994
).
Diuretic activity of Mas-DP II, an identified neuropeptide from Manduca sexta: An in vivo and in vitro examination in the adult moth
.
Arch. Insect Biochem. Physiol
27
,
3
–.
Cabantchik
Z. I.
,
Greger
R.
(
1992
).
Chemical probes for anion transporters of mammalian cell membranes
.
Am. J. Physiol
262
,
803
–.
Chamberlin
M. E.
(
1989
).
Metabolic stimulation of transepithelial potential difference across the midgut of the tobacco hornworm (Manduca sexta)
.
J. Exp. Biol
141
,
295
–.
Chijiwa
T.
,
Mishima
A.
,
Hagiwara
M.
,
Sano
M.
,
Hayashi
K.
,
Inoue
T.
,
Naito
K.
,
Toshioka
T.
,
Hidaka
H.
(
1990
).
Inhibition of forskolin-induced neurite outgrowth and protein phosphorylation by a newly synthesized selective inhibitor of cyclic AMP-dependent protein kinase, N -[2- p -bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide (H-89), of pheochromocytoma cells
.
J. Biol. Chem
265
,
5267
–.
Clark
T. M.
,
Bradley
T. J.
(
1997
).
Malpighian tubules of larval Aedes aegypti are hormonally stimulated by 5-hydroxytryptamine in response to increased salinity
.
Arch. Insect Biochem. Physiol
34
,
123
–.
Clark
T. M.
,
Hayes
T. K.
,
Beyenbach
K. W.
(
1998
).
Dose-dependent effects of CRF-like diuretic peptide on transcellular and paracellular transport pathways
.
Am. J. Physiol
274
,
834
–.
Clottens
F. L.
,
Holman
G. M.
,
Coast
G. M.
,
Totty
N. F.
,
Hayes
T. K.
,
Kay
I.
,
Mallet
A. I.
,
Wright
M. S.
,
Chung
J.-S.
,
Truong
O.
,
Bull
D. L.
(
1994
).
Isolation and characterization of a diuretic peptide common to the house fly and stable fly
.
Peptides
15
,
971
–.
Coast
G. M.
,
Wheeler
C. H.
(
1990
).
The distribution and relative potency of diuretic peptides in the house cricket, Acheta domesticus
.
Physiol. Ent
15
,
13
–.
Davies
S. A.
,
Huesmann
G. R.
,
Maddrell
S. H. P.
,
O'Donnell
M. J.
,
Skaer
N. J. V.
,
Dow
J. A. T.
,
Tublitz
N. J.
(
1995
).
CAP2b, a cardioacceleratory peptide, is present in Drosophila and stimulates tubule fluid secretion via cGMP
.
Am. J. Physiol
269
,
1321
–.
Furuya
K.
,
Schegg
K. M.
,
Schooley
D. A.
(
1998
).
Isolation and identification of a second diuretic hormone from Tenebrio molitor
.
Peptides
19
,
619
–.
Furuya
K.
,
Schegg
K. M.
,
Wang
H.
,
King
D. S.
,
Schooley
D. A.
(
1995
).
Isolation and identification of a diuretic hormone from the mealworm Tenebrio molitor
.
Proc. Natl. Acad. Sci. USA
92
,
12323
–.
Girardie
J.
,
Girardie
A.
,
Huet
J.-C.
,
Pernollet
J.-C.
(
1989
).
Amino acid sequence of locust neuroparsins
.
FEBS Lett
248
,
4
–.
Girardie
J.
,
Huet
J. C.
,
Pernollet
J. C.
(
1990
).
The locust neuroparsin-A — sequence and similarities with vertebrate and insect polypeptide hormones
.
Insect Biochem
20
,
659
–.
Goh
S. L.
,
Phillips
J. E.
(
1978
).
Dependence of prolonged water absorption by in vitro locust rectum on ion transport
.
J. Exp. Biol
72
,
25
–.
Grinstein
S.
,
Wieczorek
H.
(
1994
).
Cation antiports of animal plasma membranes
.
J. Exp. Biol
196
,
307
–.
Hanrahan
J. W.
,
Phillips
J. E.
(
1983
).
Mechanism and control of salt absorption in locust rectum
.
Am. J. Physiol
244
,
131
–.
Hanrahan
J. W.
,
Phillips
J. E.
(
1984
).
KCl transport across an insect epithelium. I. Tracer fluxes and the effects of ion substitutions
.
J. Membr. Biol
80
,
15
–.
Hayes
T. K.
,
Holman
G. M.
,
Pannabecker
T. L.
,
Wright
M. S.
,
Strey
A. A.
,
Nachman
R. J.
,
Hoel
D. F.
,
Olson
J. K.
,
Beyenbach
K. W.
(
1994
).
Culekinin depolarizing peptide: A mosquito leucokinin-like peptide that influences insect Malpighian tubule ion transport
.
Regul. Peptides
52
,
235
–.
Hayes
T. K.
,
Pannabecker
T. L.
,
Hinckley
D. J.
,
Holman
G. M.
,
Nachman
R. J.
,
Petzel
D. H.
,
Beyenbach
K. W.
(
1989
).
Leucokinins, a new family of ion transport stimulators and inhibitors in insect Malpighian tubules
.
Life Sci
44
,
1259
–.
Jeffs
L. B.
,
Phillips
J. E.
(
1996
).
Pharmacological study of the second messengers that control rectal ion and fluid transport in the desert locust (Schistocerca gregaria)
.
Arch. Insect Biochem. Physiol
31
,
169
–.
Kataoka
H.
,
Troetschler
R. G.
,
Li
J. P.
,
Kramer
S. J.
,
Carney
R. L.
,
Schooley
D. A.
(
1989
).
Isolation and identification of a diuretic hormone from the tobacco hornworm, Manduca sexta
.
Proc. Natl. Acad. Sci. USA
86
,
2976
–.
Kay
I.
,
Patel
M.
,
Coast
G. M.
,
Totty
N. F.
,
Mallet
A. I.
,
Goldsworthy
G. J.
(
1992
).
Isolation, characterization and biological activity of a CRF-related diuretic peptide from Periplaneta americana L
.
Regul. Peptides
42
,
111
–.
King
D. S.
,
Meredith
J.
,
Wang
Y. J.
,
Phillips
J. E.
(
1999
).
Biological actions of synthetic locust ion transport peptide (ITP)
.
Insect Biochem. Mol. Biol
29
,
11
–.
Lehmberg
E.
,
Ota
R. B.
,
Furuya
K.
,
King
D. S.
,
Applebaum
S. W.
,
Ferenz
H.-J.
,
Schooley
D. A.
(
1991
).
Identification of a diuretic hormone of Locusta migratoria
.
Biochem. Biophys. Res. Commun
179
,
1036
–.
Maddrell
S. H. P.
,
Herman
W. S.
,
Mooney
R. L.
,
Overton
J. A.
(
1991
).
5-Hydroxytryptamine: a second diuretic hormone in Rhodnius prolixus
.
J. Exp. Biol
156
,
557
–.
Moffett
D. F.
,
Cummings
S. A.
(
1994
).
Transepithelial potential and alkalization in an in situ preparation of tobacco hornworm (Manduca sexta) midgut
.
J. Exp. Biol
194
,
341
–.
Morgan
P. J.
,
Mordue
W.
(
1985
).
Cyclic AMP and locust diuretic hormone action. Hormone induced changes in cAMP levels offers a novel method for detecting biological activity of uncharacterized peptide
.
Insect Biochem
15
,
247
–.
Nicolson
S. W.
(
1991
).
Diuresis or clearance — is there a physiological role for the diuretic hormone of the desert beetle Onymacris?
.
J. Insect Physiol
37
,
447
–.
O'Donnell
M. J.
,
Dow
J. A. T.
,
Huesmann
G. R.
,
Tublitz
N. J.
,
Maddrell
S. H. P.
(
1996
).
Separate control of anion and cation transport in Malpighian tubules of Drosophila melanogaster
.
J. Exp. Biol
199
,
1163
–.
O'Donnell
M. J.
,
Machin
J.
(
1991
).
Ion activities and electrochemical gradients in the mealworm rectal complex
.
J. Exp. Biol
155
,
375
–.
Phillips
J. E.
,
Audsley
N.
(
1995
).
Neuropeptide control of ion and fluid transport across locust hindgut
.
Am. Zool
35
,
503
–.
Phillips
J. E.
,
Audsley
N.
,
Lechleitner
R.
,
Thomson
B.
,
Meredith
J.
,
Chamberlin
M.
(
1988
).
Some major transport mechanisms of insect absorptive epithelia
.
Comp. Biochem. Physiol
90
,
643
–.
Phillips
J. E.
,
Mordue
W.
,
Meredith
J.
,
Spring
J.
(
1980
).
Purification and characteristics of the chloride transport stimulating factor from locust corpora cardiaca: a new peptide
.
Can. J. Zool
58
,
1851
–.
Phillips
J. E.
,
Wiens
C.
,
Audsley
N.
,
Jeffs
L.
,
Bilgen
T.
,
Meredith
J.
(
1996
).
Nature and control of chloride transport in insect absorptive epithelia
.
J. Exp. Zool
275
,
292
–.
Proux
B. H.
,
Proux
J. P.
,
Phillips
J. E.
(
1984
).
Antidiuretic action of corpus cardiacum (CTSH) on long-term fluid absorption across locust recta in vitro
.
J. Exp. Biol
113
,
409
–.
Ramsay
J. A.
(
1964
).
The rectal complex of the mealworm Tenebrio molitor L. (Coleoptera, Tenebrionidae)
.
Phil. Trans. R. Soc. Lond
248
,
279
–.
Ramsay
J. A.
(
1976
).
The rectal complex in the larvae of Lepidoptera
.
Phil. Trans. R. Soc. Lond
274
,
203
–.
Reynolds
S. E.
,
Bellward
K.
(
1989
).
Water balance in Manduca sexta caterpillars: water recycling from the rectum
.
J. Exp. Biol
141
,
33
–.
Veenstra
J. A.
(
1994
).
Isolation and identification of three leucokinins from the mosquito Aedes aegypti
.
Biochem. Biophys. Res. Commun
202
,
715
–.
Wheeler
C. H.
,
Coast
G. M.
(
1990
).
Assay and characterisation of diuretic factors in insects
.
J. Insect Physiol
36
,
23
–.
Wieczorek
H.
(
1992
).
The insect V-ATPase, a plasma membrane proton pump energizing secondary active transport: molecular analysis of electrogenic potassium transport in the tobacco hornworm midgut
.
J. Exp. Biol
172
,
335
–.
Yamamoto
R. T.
(
1969
).
Mass rearing of the tobacco hornworm. II. Larval rearing and pupation
.
J. Econ. Ent
62
,
1427
–.
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