Vascular effects of helodermin, helospectin I and helospectin II : a comparison with vasoactive intestinal peptide (VIP)

• 1. Helodermin, helospectin I and helospectin II, peptides recently isolated from the salivary gland venom of Heloderma suspectum, were compared to vasoactive intestinal peptide (VIP) with respect to effects on systemic blood pressure and on isolated femoral arteries in the rat. 2. They all reduced blood pressure in a dose-dependent manner; helodermin was less effective than VIP. However, at doses higher than 1 nmol kg-1 all four peptides reduced blood pressure to about the same extent. 3. The half-life of the hypotensive effect of VIP was longer than that of helodermin and the helospectins. 4. VIP and helodermin were equally potent in relaxing femoral arteries precontracted with phenylephrine or prostaglandin F2 alpha. 5. Helospectin I and II relaxed phenylephrine-contracted vessels to the same extent as VIP but with a lower potency. 6. Addition of VIP 1 microM to preparations exposed to helodermin 1 microM or to either of the helospectins did not produce a further relaxation. 7. The findings indicate that VIP, helodermin and helospectin I and II have a similar profile of action and therefore may act on a common receptor.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Farmakologi och toxikologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Pharmacology and Toxicology (hsv//eng)

Nyckelord

Amino Acid Sequence

Animals

Blood Pressure/drug effects

Dinoprost/pharmacology

Female

Half-Life

Hemodynamics/drug effects

In Vitro Techniques

Male

Molecular Sequence Data

Peptides/pharmacology

Phenylephrine/pharmacology

Rats

Rats, Inbred Strains

Vasoactive Intestinal Peptide/pharmacology

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)