The crop as an organ of glyceride absorption in the American cockroach, <i>Periplaneta americana</i> L.

Hoffman, A. G. D.; Downer, Roger

doi:10.1139/z76-133

Cited by 30 publications

(2 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The major functions of the insect foregut are uptake, mechanical grinding, and temporary storage of food before its transfer through the proventriculus to the midgut, where enzymatic digestion and nutrient absorption take place ( Chapman, 2013 ; Denecke et al, 2018 ; Holtof et al, 2019 ). Although the permeability of the foregut is generally considered to be very low ( Maddrell and Gardiner, 1980 ), some insect species have been reported to absorb lipophilic compounds, such as cholesterol from the crop ( Hoffman and Downer, 1976 ; Joshi and Agarwal, 1977 ). In addition, lipophilic insecticides have been shown to be taken up into foregut tissue of the honeybee Apis mellifera ( Conner et al, 1978 ).…”

Section: Discussionmentioning

confidence: 99%

Rapid and Selective Absorption of Plant Defense Compounds From the Gut of a Sequestering Insect

et al. 2022

View full text Add to dashboard Cite

Many herbivorous insects exploit defense compounds produced by their host plants for protection against predators. Ingested plant defense compounds are absorbed via the gut epithelium and stored in the body, a physiological process that is currently not well understood. Here, we investigated the absorption of plant defense compounds from the gut in the horseradish flea beetle, Phyllotreta armoraciae, a specialist herbivore known to selectively sequester glucosinolates from its brassicaceous host plants. Feeding experiments using a mixture of glucosinolates and other glucosides not found in the host plants showed a rapid and selective uptake of glucosinolates in adult beetles. In addition, we provide evidence that this uptake mainly takes place in the foregut, whereas the endodermal midgut is the normal region of absorption. Absorption via the foregut epithelium is surprising as the apical membrane is covered by a chitinous intima. However, we could show that this cuticular layer differs in its structure and overall thickness between P. armoraciae and a non-sequestering leaf beetle. In P. armoraciae, we observed a thinner cuticle with a less dense chitinous matrix, which might facilitate glucosinolate absorption. Our results show that a selective and rapid uptake of glucosinolates from the anterior region of the gut contributes to the selective sequestration of glucosinolates in P. armoraciae.

show abstract

Section: Discussionmentioning

confidence: 99%

Rapid and Selective Absorption of Plant Defense Compounds From the Gut of a Sequestering Insect

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Individual insects were isolated in Petri dishes and held undisturbed for a period of 12 to 16 h prior to dissection. All dissections were performed within 5 min, under ice-cold CPS [12]. Malpighian tubules were removed intact, attached to a section of gut less than 2 mm in length.…”

Section: Materials and Methods Animalsmentioning

confidence: 99%

Effects of potential inhibitors on N‐acetylation of octopamine by tissue extracts from malpighian tubules and cerebral ganglia of Periplaneta americana L

Martin

Downer

1989

Arch Insect Biochem Physiol

View full text Add to dashboard Cite

N-acetyltransferase activity in extracts of Malpighian tubules and cerebral ganglia from Periplaneta americana L. was monitored using high performance liquid chromatography with coulometric electrochemical detection. Several potential inhibitors were tested against the tissue preparations, and the results indicate distinct differences in the nature of the enzyme derived from the two sources. The Malpighian tubule and cerebral ganglia extracts were sensitive to sulfhydryl inhibition and divalent cations, and both preparations also showed end-product inhibition with coenzyme A. Juglone, an inhibitor of choline acetyltransferase, inhibits N-acetyltransferase activity from both tissues; however, separate studies with choline indicate that the N-acetylation observed in this study is not due to choline acetyltransferase. A number of phenyl, phenol, catechol and indole derivatives were tested and the results indicate that the presence of a 4-hydroxyl group on the phenol ring enhances the capacity of phenol and catechol derivatives to inhibit N-acetyltransferase. Demethylchlordimeform inhibits the production of N-acetyl-p-Octopamine by Malpighian tubule preparations and intact tissues whereas other formamidines, BTS-27271 and amitraz, inhibit N-acetyl-p-Octopamine production only in intact tissues.

show abstract

Pharmacology of octopamine‐, dopamine‐, and 5‐hydroxytryptamine‐stimulated cyclic amp accumulation in the corpus cardiacum of the american cockroach, Periplaneta americana L

Gole

Orr

Downer

1987

Arch Insect Biochem Physiol

View full text Add to dashboard Cite

A variety of potential receptor agonists were incubated with isolated corpora cardiaca from the American cockroach Periplaneta americana to determine their effects o n cyclic AMP production in this gland. Octopamine, dopamine, and 5-hydroxytryptamine elevated cyclic AMP levels in a dose-dependent manner with estimated K, values of 15.8, 1.7, and 1.1 pM, respectively, and their stimulation was found to be additive. Several vertebrate receptor antagonists were tested against the three amines and a preliminary pharmacological profile developed.

show abstract

The crop as an organ of glyceride absorption in the American cockroach, Periplaneta americana L.

Cited by 30 publications

References 32 publications

Rapid and Selective Absorption of Plant Defense Compounds From the Gut of a Sequestering Insect

Rapid and Selective Absorption of Plant Defense Compounds From the Gut of a Sequestering Insect

Effects of potential inhibitors on N‐acetylation of octopamine by tissue extracts from malpighian tubules and cerebral ganglia of Periplaneta americana L

Pharmacology of octopamine‐, dopamine‐, and 5‐hydroxytryptamine‐stimulated cyclic amp accumulation in the corpus cardiacum of the american cockroach, Periplaneta americana L

Contact Info

Product

Resources

About