title: Blood-finding strategy of a capillary-feeding sandfly, Lutzomyia longipalpis.
abstract: Salivary gland homogenates of adult female Lutzomyia longipalpis inhibited platelet aggregation induced by ADP and collagen. Apyrase (ATP diphosphohydrolase) activity was prominent, requiring Ca2+ but not Mg2+ and a pH optimum of 8.0. Human as well as rabbit hosts developed a well delimited erythema, evident 2-3 min after initial probing and lasting for as long as 2 days. Erythema, not accompanied by itching or swelling, developed in previously exposed hosts as well as in those not previously exposed to this insect. When injected intradermally into the shaved back of a rabbit, salivary gland homogenates induced marked erythema, even with 1/250 of a homogenized salivary gland. This erythema-inducing factor was insoluble in 90% ethanol and was destroyed by incubation with trypsin. These apyrase and erythema-inducing factors, together with short mouthpart stylets, appear to adapt Lutzomyia sandflies to feed on blood released from superficial skin capillaries.
authors.forename: J M
authors.initials: JM
authors.lastname: Ribeiro
authors.forename: P A
authors.initials: PA
authors.lastname: Rossignol
authors.forename: A
authors.initials: A
authors.lastname: Spielman
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D000818:Animals; D001081:Apyrase / Q000378:metabolism; D001769:Blood; D002196:Capillaries; D003094:Collagen / Q000494:pharmacology; D004175:Diptera / Q000502:physiology*; D004890:Erythema / Q000139:chemically induced; D005260:Female; D006801:Humans; D010974:Platelet Aggregation / Q000187:drug effects*; D011817:Rabbits; D012469:Salivary Glands / Q000502:physiology; D014020:Tissue Extracts / Q000494:pharmacology*
chemical_list: D014020:Tissue Extracts; D000244:Adenosine Diphosphate; D003094:Collagen; D001081:Apyrase