Ovalbumin (OA) and the calcium ionophore A23187 induced a dose-dependent contraction of guinea pig tracheal strips. The OA-induced contraction (of sensitized trachea) consisted of an initial peak concentration, maximal between 5 and 10 min, followed by a very gradual decline from the peak. On the ot...

Bovine slow-reacting substance of anaphylaxis (SRS-A) is capable of producing dose-dependent vascular permeability changes in the skin of calves. The wheals are well-defined indurations, similar to wheals induced by histamine but different from those induced by prostaglandin E2 (PGE). Three proposed...

Antigen challenge in vivo of rat peritoneal cells (enriched with monocytes and polymorphonuclear leucocytes) passively sensitized 2 h previously with homologous antibody of the IgGa class released large amounts of slow-reacting substance of anaphylaxis (SRS-A, 1739 +/- 59 u/ml) into the peritoneal f...

A ninhydrin positive compound (L2) now identified as 2-amino-5-(N-ethylcarboxyamido)-pentanoic acid, from unprocessed tea leaves was a potent inhibitor of thrombin-stimulated thromboxane formation in rabbit whole blood (Ali and Afzal; Prostaglandins, Leukotrienes and Medicine, 27: 9, 1987). In the p...

Experiments were conducted to examine the variability between Atlantic salmon parr acclimated to 7 degrees C (n=150) and those acclimated to 14 degrees (n=150) over a year. Fish were stocked into tanks (2.32 x 2.32 x 0.52 m) at 10.5 kg/msuperscript 3. The condition factor remained similar for both g...

13th Annual Meeting of the Aquaculture Association of Canada, Ottawa, Ont., June 4.

7th Annual APICS Aquaculture Conf., Truro, NS., March 8

14th Annual Meeting of the Aquaculture Association of Canada, Quebec City, June 10-12

Medetomidine proved to be an effective sedative in rainbow trout but not an anaesthetic; its effects were antagonized by atipamezole. The clinical signs of medetomidine sedation were rapid settling to the bottom of the tank followed by progressive ataxia. The sedative effect was dose-dependent: at 1...

Large-conductance calcium-dependent potassium (maxi-K) channels play an important role in regulating the tone of airway smooth muscle and the release of bronchoconstrictive substances from nerves in the lung. Crude extracts of Desmodium adscendens, a medicinal herb used in Ghana as a treatment for a...

Mellavax (avirulent S. dublin vaccine) appears to cause an anaphylactoid reaction in a ratio of 1:28 000 doses sold. A clinical picture of respiratory embarrassment and pulmonary oedema occurs. Histamine, 5-HT and dopamine are implicated mediators released during the reaction but to a minor extent c...

Ovalbumin induces contraction of sensitized guinea-pig trachea, both in the presence and absence of indomethacin. Cascade superfusion bioassay was employed to detect mediator release. A prostaglandin E-like material was released in response to antigen in the absence of indomethacin but, no biologica...