The isolated, perfused bovine ear. A model for pharmacological study of cutaneous vasculature and anaphylaxis

Abstract

Bovine ears were catheterized and perfused with Krebs-Henseleit (K-H) solution at a constant flow rate. The perfusion pressure (PP) was monitored using a pressure transducer coupled to a carrier preamplifier, amplifier and a pen recorder. Dose-response curves to phenylephrine, histamine and 5-hydroxytryptamine were obtained. The ear preparations responded to these agonists dose-dependently by increases in perfusion pressure. Ear preparations from sensitized calves were challenged with 0.05 ml of horse serum which caused increased perfusion pressure. These preliminary results suggest that the perfused bovine ear represents a promising, simple, inexpensive model for the study of pharmacological mechanisms of the skin.

The vascular responses of the isolated perfused bovine external ear to exogenous histamine and 5-HT (serotonin)

“…Responses to histamine were also inhibited by cimetidine (10-mol/L) (Figure 1), which shifted the concentration-response curve of histamine to the right by a factor of less than 10, while the slope remained unchanged. The biphasic responses produced by histamine (10 -4 mol/L to 5 x 10 -3 mol/L), which we reported in our preliminary work (Eghianruwa and Eyre, 1991), were reduced by atropines(10-5 mol/L) (Figure 2), mepyrami.~e (10 -8 mol/L) ( Figure 3) and cimetidine (10-mol/L) (Figure 4). Atropine (10 -6 mol/L) inhibited the vascular responses to histamine ( Figure 1) with a change in the slope of the concentration-response curve for 6 histamine.…”

“…The procedure was that described previously by Eghianruwa and Eyre (1991). Briefly, Krebs-Henseleit (K-H) solution containing, in grams per litre, NaC1 6.9, KC1 0.33, CaCI 2 .0 28, KH 2PO 4 0 .16, NaHCO 3.…”