Multiple vasoactive factors in epidermal secretions of the Arabian Gulf catfish, Arius bilineatus (Valenciennes).
1. The Arabian Gulf catfish produces proteinaceous epidermal secretions when threatened or injured. 2. The soluble fraction of the catfish epidermal secretions (SES) has vasoconstrictor activities on sheep renal arteries, which can be inhibited by several antagonists, including atropine, indomethacin, prazosin, and verapamil. 3. Mepyramine, yohimbine, and ketanserin have negligible effects on SES-induced contraction. 4. SES exhibits a significant tachyphylaxis upon addition of a second (8.4% reduction) and third (47% reduction) dose of SES to the organ bath, which can be partially prevented by addition of a fresh arterial section prior to each addition. 5. A vasoconstricting activity has been partially purified from SES by gel filtration on Fractogel HW-65(F) and appears to be a protein with a pI near 7.3. This activity is affected only by verapamil and prazosin.
al-Bow
H A
HA
Department of Biochemistry, Faculty of Science, Kuwait University, Safat, Kuwait.
al-Hassan
J M
JM
Thomson
M
M
Thulesius
O
O
Elkhawad
A
A
D000818:Animals; D002397:Catfishes / Q000502:physiology*; D002850:Chromatography, Gel; D004817:Epidermis / Q000378:metabolism*; D066298:In Vitro Techniques; D019156:Indian Ocean; D007525:Isoelectric Focusing; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D012077:Renal Artery / Q000187:drug effects* / Q000502:physiology; D012756:Sheep; D013618:Tachyphylaxis / Q000502:physiology; D014662:Vasoconstrictor Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
D011506:Proteins; D014662:Vasoconstrictor Agents