Histopathological characterization of experimentally induced cutaneous loxoscelism in rabbits inoculated with Loxosceles similis venom
Envenomation by Loxosceles bites is characterized by dermonecrotic and/or systemic features that lead to several clinical signs and symptoms called loxoscelism. Dermonecrotic lesions are preceded by thrombosis of the dermal plexus. Recent studies show that atheromatous plaque is prone to thrombosis due to endothelial cell apoptosis. To the best of our knowledge, there are no reports of microscopic dermal lesion and endothelial cell apoptosis induced by Loxosceles similis venom in the literature. Thus, the aim of the present study is to describe histological lesions induced by L. similis venom in rabbit skin and to elucidate whether apoptosis of endothelial cells is involved in the pathogenesis of loxoscelism. Forty male rabbits were split into two groups: the control group (intradermally injected with 50 µL of PBS) and the experimental group (intradermally injected with 0.5 µg of L. similis crude venom diluted in 50 µL of PBS). After 2, 4, 6 and 8 hours of injection, skin fragments were collected and processed for paraffin or methacrylate embedding. Sections of 5 µm thick were stained by HE, PAS or submitted to TUNEL reaction. Microscopically, severe edema, diffuse heterophilic inflammatory infiltrate, perivascular heterophilic infiltrate, thrombosis, fibrinoid necrosis of arteriolar wall and cutaneous muscle necrosis were observed. Two hours after venom injection, endothelial cells with apoptosis morphology were evidenced in the dermal plexus. Apoptosis was confirmed by TUNEL reaction. It seems that endothelial cell apoptosis and its consequent desquamation is an important factor that induces thrombosis and culminates in dermonecrosis, which is characteristic of cutaneous loxoscelism.
Auteurs principaux: | Pereira,NB, Kalapothakis,E, Vasconcelos,AC, Chatzaki,M, Campos,LP, Vieira,FO, Verçosa,BLA, Silva,SS, Ferreira,WM, Moro,L |
---|---|
Format: | Digital revista |
Langue: | English |
Publié: |
Centro de Estudos de Venenos e Animais Peçonhentos (CEVAP/UNESP)
2012
|
Accès en ligne: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992012000300005 |
Tags: |
Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
|
Documents similaires
-
Cutaneous-visceral loxoscelism due to spider bite Loxosceles laeta in children: associated factors
par: Juárez S., Rosa, et autres
Publié: (2023) -
PARTIAL CHARACTERIZATION OF THE SPIDER LOXOSCELES GAUCHO VENOM
par: Barbaro,K.C.
Publié: (1995) -
Cutaneous loxoscelism: extensive nonulcerated livedoid plaque
par: Torres,Natalie, et autres
Publié: (2017) -
Evaluation of mesenchymal cells and dapsone for the treatment of dermonecrotic wounds caused by Loxosceles laeta venom in rabbits
par: Martins,Guilherme de Caro, et autres
Publié: (2022) -
Search of intravascular hemolysis in patients with the cutaneous form of loxoscelism
par: Morena,Pasquale, et autres
Publié: (1994)