Pharmacological and biochemical studies on the venom of a clinically important viper snake (Echis carinatus) of Pakistan.
Echis carinatus (saw-scaled viper) has been the major culprit responsible for serious envenomation casualties throughout the subcontinent. The present study describes the electrophoretic and zymographic characterization of E. carinatus venom and its effect on mammalian smooth muscle. Crude venom showed the presence of disintegrin, PLA2, C-type lectin/lectin-like components, CRISP, Serine protease, l-amino acid oxidase and very high concentrations of SVMPs. E. carinatus venom (1, 10, 30, 50, 100 μg/ml) inhibited the active tension/force of muscle contraction in a time and concentration dependent manner. The observed effects abolished when the venom was heated at 100 °C for 5 min. However, a decrease in bath temperature from 37 °C to 26 °C or an increase in CaCl2 concentration to 5 mM did not prevent the inhibition of contractile activity. The contractile response elicited by exogenous application of 50 mM KCl and 1 μM acetylcholine (ACh) was also significantly inhibited by all venom concentrations. Prior administration of commercially available polyvalent anti-venom partially neutralized and prevented the effect of E. carinatus venom whereas addition of anti-venom at t50 failed to reverse the inhibitory effect. Studies on isolated intestinal muscle indicate involvement of myotoxic and apoptotic components in E. carinatus venom for irreversible damage to muscle tissue.
Neuromuscular Research Unit, Department of Physiology, University of Karachi, Karachi 75270, Pakistan; H.E.J Research Institute of Chemistry, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan.
Arifa
A
Savanur
H.E.J Research Institute of Chemistry, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan. Electronic address: dr.syedabidali@gmail.com.
Syed Abid
SA
Ali
H.E.J Research Institute of Chemistry, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan.
Iqra
I
Munir
H.E.J Research Institute of Chemistry, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan.
Atiya
A
Abbasi
H.E.J Research Institute of Chemistry, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan.
Mehtab
M
Alam
Neuromuscular Research Unit, Department of Physiology, University of Karachi, Karachi 75270, Pakistan.
Hilal Ahmed
HA
Shaikh
D000818:Animals; D000997:Antivenins / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007422:Intestines / Q000187:drug effects; D050830:L-Amino Acid Oxidase; D037181:Lectins, C-Type; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D010154:Pakistan; D011817:Rabbits; D012909:Snake Bites / Q000188:drug therapy; D014757:Viper Venoms / Q000737:chemistry* / Q000494:pharmacology*; D017819:Viperidae
D000997:Antivenins; D037181:Lectins, C-Type; D014757:Viper Venoms; D050830:L-Amino Acid Oxidase
Acetylcholine; Active tension; Contracture; Echis carinatus venom; Potassium chloride; Rabbit ileum