Vasodilator activity of venom involves activation of the NO/cGMP pathway and inhibition of calcium influx to vascular smooth muscle cells.

Tarantula venoms may be a natural source of new vasodilator components useful in pharmacological research. Moreover, biological function data of the venoms are important to enhance the knowledge about the biodiversity and evolution of these species. The present study aims to describe the vasodilatory activity induced by the venom of on isolated rat aortic rings.

A subfraction obtained from the venom of the tarantula contains inhibitor cystine knot peptides and induces relaxation of rat aorta by inhibiting L-type voltage-gated calcium channels.

Venoms from tarantulas contain low molecular weight vasodilatory compounds whose biological action is conceived as part of the envenomation strategy due to its propagative effects. However, some properties of venom-induced vasodilation do not match those described by such compounds, suggesting that other toxins may cooperate with these ones to produce the observed biological effect. Owing to the distribution and function of voltage-gated ion channels in blood vessels, disulfide-rich peptides isolated from venoms of tarantulas could be conceived into potential vasodilatory compounds.

Snake Venom Hemotoxic Enzymes: Biochemical Comparison between Species from Central Mexico.

Snakebite envenoming is a serious medical problem in different areas of the world. In Latin America, the major prevalence is due to snakes of the family , where rattlesnakes () are included. They produce hemotoxic venom which causes bleeding, tissue degradation and necrosis.

Rat aorta relaxation induced by the venom of Poecilotheria regalis involves the activation of the NO/cGMP pathway.

Spider venoms are widely recognized as a new emerging source of potential research tools, pesticides, drug leads, and therapeutic agents. Some studies suggest that these venoms may contain interesting vasodilator compounds with potential therapeutic applications. In the present study, the vasodilator activity of the venom of Poecilotheria regalis was evaluated in isolated rat aortic rings.

Hyaluronidase-like enzymes are a frequent component of venoms from theraphosid spiders.

Theraphosid spider venoms are extremely complex mixtures, composed mainly by low molecular compounds, peptides, and enzymes. The large size of these spiders and their ability to breed in captivity permits access to rather large amounts of venom and an easier venom extraction. In the present study, we conducted a comparative investigation about the content of hyaluronidase-like enzymes in the venoms from several theraphosid spiders, with a special focus on the Poecilotheria species, which are considered as underestimated theraphosids of medical importance.

Pharmacological characterization of venoms from three theraphosid spiders: Poecilotheria regalis, Ceratogyrus darlingi and Brachypelma epicureanum.

Background: Tarantulas (Theraphosidae) represent an important source of novel biologically active compounds that target a variety of ion channels and cell receptors in both insects and mammals. In this study, we evaluate and compare the pharmacological activity of venoms from three taxonomically different theraphosid spiders bred in captivity: Poecilotheria regalis, an aggressive arboreal tarantula from southeastern India; Ceratogyrus darlingi, an aggressive tarantula from southern Africa; and Brachypelma epicureanum, a docile tarantula from the Yucatan dry forest of Mexico. Prior to this study, no research had been conducted with regard to the composition and pharmacological activity of these venoms.